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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Glob. Womens Health</journal-id>
<journal-title>Frontiers in Global Women's Health</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Glob. Womens Health</abbrev-journal-title>
<issn pub-type="epub">2673-5059</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3389/fgwh.2023.1128988</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Global Women's Health</subject>
<subj-group>
<subject>Original Research</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Incidence and predictors of loss to follow-up among pregnant and lactating women in the Option B&#x002B; PMTCT program in Northwestern Ethiopia: a seven-year retrospective cohort study</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" corresp="yes"><name><surname>Azanaw</surname><given-names>Melkalem Mamuye</given-names></name>
<xref ref-type="aff" rid="aff1"><sup>1</sup></xref>
<xref ref-type="corresp" rid="cor1">&#x002A;</xref><uri xlink:href="https://loop.frontiersin.org/people/1339228/overview" /></contrib>
<contrib contrib-type="author"><name><surname>Baraki</surname><given-names>Adhanom Gebreegziabher</given-names></name>
<xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib>
<contrib contrib-type="author"><name><surname>Yenit</surname><given-names>Melaku Kindie</given-names></name>
<xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib>
</contrib-group>
<aff id="aff1"><label><sup>1</sup></label><addr-line>Department of Public Health, College of Health Sciences</addr-line>, <institution>Debre Tabor University</institution>, <addr-line>Debre Tabor</addr-line>, <country>Ethiopia</country></aff>
<aff id="aff2"><label><sup>2</sup></label><addr-line>Department of Epidemiology and Biostatistics, Institute of Public Health, College of Medicine and Health Science</addr-line>, <institution>University of Gondar</institution>, <addr-line>Gondar</addr-line>, <country>Ethiopia</country></aff>
<author-notes>
<fn fn-type="edited-by"><p><bold>Edited by:</bold> Mat Lowe, Society for the Study of Women&#x0027;s Health, Gambia</p></fn>
<fn fn-type="edited-by"><p><bold>Reviewed by:</bold> Benjamin Kofi Kujabi, National Taipei University of Technology, Taiwan Haddy Bah, Edward Francis Small Teaching Hospital, Gambia</p></fn>
<corresp id="cor1"><label>&#x002A;</label><bold>Correspondence:</bold> Melkalem Mamuye Azanaw <email>melkalem21@gmail.com</email></corresp>
<fn fn-type="other" id="fn001"><p>Abbreviations AHR, adjusted hazard ratio; AIDS, acquired immunodeficiency syndrome; ART, antiretroviral therapy; CD4, cluster of differentiation T-4 cells; CHR, crude hazard ratio; CI, confidence interval; CPT, co-trimoxazole preventive therapy; eMTCT, elimination of mother to child transmission; HIV, human immunodeficiency virus; LTFU, lost to follow-up; MUAC, mid-upper arm circumference; OI, opportunistic infections; PMTCT, prevention of mother to child transmission; WHO, World Health Organization.</p></fn>
</author-notes>
<pub-date pub-type="epub"><day>17</day><month>07</month><year>2023</year></pub-date>
<pub-date pub-type="collection"><year>2023</year></pub-date>
<volume>4</volume><elocation-id>1128988</elocation-id>
<history>
<date date-type="received"><day>05</day><month>01</month><year>2023</year></date>
<date date-type="accepted"><day>21</day><month>06</month><year>2023</year></date>
</history>
<permissions>
<copyright-statement>&#x00A9; 2023 Azanaw, Baraki and Yenit.</copyright-statement>
<copyright-year>2023</copyright-year><copyright-holder>Azanaw, Baraki and Yenit</copyright-holder><license license-type="open-access" xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the <ext-link ext-link-type="uri" xlink:href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution License (CC BY)</ext-link>. The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p></license>
</permissions>
<abstract>
<sec><title>Introduction</title>
<p>Although Ethiopia has implemented the Option B&#x002B; program over the past 7&#x2005;years, loss to follow-up among HIV-positive women remains a major problem for antiretroviral therapy (ART) treatment. This study was conducted to investigate the number of women who dropped out of follow-up after the Option B&#x002B; program.</p>
</sec>
<sec><title>Methods</title>
<p>A retrospective follow-up study was conducted among 403 pregnant and lactating women between June 2013 and December 2019 at health facilities in Northwest Ethiopia. The Cox proportional hazards regression model was used to identify predictors of loss to follow-up. The results were reported as hazard ratios with 95&#x0025; confidence intervals (CIs) at a significance level of <italic>p</italic>&#x2009;&#x003D;&#x2009;0.05.</p>
</sec>
<sec><title>Results</title>
<p>The overall incidence rate of loss to follow-up was 9.4 per 1,000 person-months of observation (95&#x0025; CI: 7.40&#x2013;11.90). According to the multivariable Cox regression, rural residency [adjusted hazard ratio (AHR): 2.30; 95&#x0025; CI: 1.08&#x2013;4.88], being a Muslim religion follower (AHR: 2.44; 95&#x0025; CI: 1.23&#x2013;4.81), having no baseline viral load measurement (AHR: 4.21; 95&#x0025; CI: 2.23&#x2013;7.96), being on ART before enrolment (AHR: 0.30; 95&#x0025; CI: 0.15&#x2013;0.62), having drug side effects (AHR:1.82; 95&#x0025; CI: 1.01&#x2013;3.33), same-day ART initiation (AHR: 3.23; 95&#x0025; CI: 1.53&#x2013;6.84), and having suboptimal adherence level (AHR: 3.96; 95&#x0025; CI: 2.18&#x2013;7.19) were significant predictors of loss to follow-up.</p>
</sec>
<sec><title>Conclusion</title>
<p>The incidence of loss to follow-up is lower as compared to evidence from most African countries but slightly higher than the WHO target. It is better to strengthen and expand viral load measurements for all women and to pay attention to women residing in rural areas with fair or poor adherence levels.</p>
</sec>
</abstract>
<kwd-group>
<kwd>HIV</kwd>
<kwd>women</kwd>
<kwd>loss to follow-up</kwd>
<kwd>option B&#x002B;</kwd>
<kwd>PMTCT</kwd>
<kwd>Northwest Ethiopia</kwd>
</kwd-group>
<contract-num rid="cn001">IPH/837/6/2012</contract-num>
<contract-sponsor id="cn001">University of Gondar</contract-sponsor>
<counts>
<fig-count count="4"/>
<table-count count="4"/><equation-count count="0"/><ref-count count="49"/><page-count count="0"/><word-count count="0"/></counts><custom-meta-wrap><custom-meta><meta-name>section-at-acceptance</meta-name><meta-value>Maternal Health</meta-value></custom-meta></custom-meta-wrap>
</article-meta>
</front>
<body>
<sec id="s1" sec-type="intro"><title>Introduction</title>
<p>Globally, an estimated 180,000 new pediatric infections were reported annually in 2018 (<xref ref-type="bibr" rid="B1">1</xref>). Mother-to-child transmission (MTCT) accounts for 90&#x0025; of these new pediatric infections and may be transmitted <italic>in utero</italic>, labor, delivery, or breastfeeding (<xref ref-type="bibr" rid="B2">2</xref>). Without any intervention, MTCT ranged from 15&#x0025; to 45&#x0025;. However, antiretroviral treatment and other interventions can reduce this risk to below 5&#x0025; in breastfeeding women and 2&#x0025; in non-breastfeeding women (<xref ref-type="bibr" rid="B2">2</xref>&#x2013;<xref ref-type="bibr" rid="B4">4</xref>).</p>
<p>The Joint United Nations Program on HIV/AIDS set a target for member states to have virtual elimination of MTCT to less than 5&#x0025; and 90&#x0025; reduction of new human immunodeficiency virus (HIV) infections among young children by 2015, and moved the global commitment to eliminate MTCT by 2020 and the HIV epidemic in 2030 (<xref ref-type="bibr" rid="B1">1</xref>). Moreover, the World Health Organization recommends the Option B&#x002B; program to prevent MTCT transmission of HIV infection. Option B&#x002B; program is the provision of universal, lifelong antiretroviral therapy (ART) for all HIV-infected individuals regardless of CD4 count and WHO clinical staging as a &#x201C;Test and Treat&#x201D; approach in 2016 (<xref ref-type="bibr" rid="B2">2</xref>, <xref ref-type="bibr" rid="B5">5</xref>&#x2013;<xref ref-type="bibr" rid="B7">7</xref>). These strategies are directly related to an increase in the coverage of antiretroviral medicines taken by pregnant women living with HIV from 51&#x0025; in 2010 to 80&#x0025; in 2017 to prevent MTCT (<xref ref-type="bibr" rid="B1">1</xref>). In addition to this, these programs contributed to the reduction of maternal mortality by 44&#x0025; between 1990 and 2015 (<xref ref-type="bibr" rid="B8">8</xref>) and the aversion to 1.4 million new child infections since 2010 (<xref ref-type="bibr" rid="B1">1</xref>). Despite these efforts, loss to follow-up (LTFU) and poor adherence to drugs remain major challenges in achieving virtual elimination of MTCT of HIV, especially in sub-Saharan Africa (<xref ref-type="bibr" rid="B9">9</xref>). Loss to follow-up in the prevention of mother to child transmission (PMTCT) program had an impact on women&#x0027;s access to HIV care and treatment, which led to an advanced HIV stage, increased maternal HIV/acquired immunodeficiency syndrome (AIDS)-related morbidity and mortality, vertical transmission of HIV to newborns, development of drug resistance, and missed opportunities for family planning (<xref ref-type="bibr" rid="B2">2</xref>, <xref ref-type="bibr" rid="B10">10</xref>). Moreover, LTFU has consequences for future pregnancies of child health and survival and increases the risk of transmission if the partner is serodiscordant (<xref ref-type="bibr" rid="B2">2</xref>).</p>
<p>Different studies have indicated that the incidence of LTFU among HIV-positive pregnant and lactating mothers in the PMTCT program varies in different countries. The incidence rates of LTFU in Brazil (<xref ref-type="bibr" rid="B11">11</xref>) and Myanmar (<xref ref-type="bibr" rid="B12">12</xref>) among mother&#x2013;child pairs and pregnant women in the PMTCT program were 15.4&#x0025; and 7 per 1,000 person-years, respectively. Moreover, the incidence of LTFU among pregnant and lactating mothers under the Option B&#x002B; program remains high in different African countries, ranging from 16&#x0025; to 53.7&#x0025; (<xref ref-type="bibr" rid="B9">9</xref>, <xref ref-type="bibr" rid="B13">13</xref>&#x2013;<xref ref-type="bibr" rid="B26">26</xref>). Previous studies in Ethiopia have shown that the rate of LTFU among women under the Option B&#x002B; program varies from region to region. A retrospective follow-up study at different public health facilities in the northeast regions of Ethiopia showed that the cumulative incidence of LTFU was 16.5&#x0025; (<xref ref-type="bibr" rid="B27">27</xref>). Other findings revealed that cumulative incidence was 15.4&#x0025; with an incidence rate of 9 per 1,000 person-months (PM) in western Ethiopia (<xref ref-type="bibr" rid="B28">28</xref>) and 18.2&#x0025; in western Oromia (<xref ref-type="bibr" rid="B29">29</xref>).</p>
<p>Based on different studies, maternal age less than 25 years (<xref ref-type="bibr" rid="B9">9</xref>, <xref ref-type="bibr" rid="B13">13</xref>, <xref ref-type="bibr" rid="B15">15</xref>, <xref ref-type="bibr" rid="B21">21</xref>, <xref ref-type="bibr" rid="B26">26</xref>, <xref ref-type="bibr" rid="B30">30</xref>, <xref ref-type="bibr" rid="B31">31</xref>), lower educational status (<xref ref-type="bibr" rid="B15">15</xref>, <xref ref-type="bibr" rid="B32">32</xref>), unmarried marital status (<xref ref-type="bibr" rid="B19">19</xref>), unemployment status (<xref ref-type="bibr" rid="B26">26</xref>), positive partner HIV status (<xref ref-type="bibr" rid="B9">9</xref>, <xref ref-type="bibr" rid="B16">16</xref>), baseline low CD4 cell counts and high viral load measurement (<xref ref-type="bibr" rid="B33">33</xref>, <xref ref-type="bibr" rid="B35">35</xref>), WHO clinical stage 3/4 (<xref ref-type="bibr" rid="B23">23</xref>), treatment on the same day of initiation as HIV diagnosis (<xref ref-type="bibr" rid="B20">20</xref>, <xref ref-type="bibr" rid="B23">23</xref>), new enrolment in PMTCT services, drug side effects, and changes in the treatment regimen (<xref ref-type="bibr" rid="B15">15</xref>, <xref ref-type="bibr" rid="B36">36</xref>&#x2013;<xref ref-type="bibr" rid="B38">38</xref>) were significant predictors of LTFU.</p>
<p>Although there are studies on LTFU among the general adult population on ART care, there are no published studies on the incidence of LTFU and its predictors among HIV-positive pregnant and lactating mothers on ART treatment since the start of the Option B&#x002B; program. The findings of this study will help health institution managers and programmers develop evidence-based interventions to promote retention in care for both mothers and infants, because early identification of magnitude and factors helps identify vital sites and improve women with HIV by enhancing viral suppression. The findings of this study will also assist policymakers and programmers in focusing on the major identified risk factors for LTFU among HIV-positive women to improve PMTCT services and eradicate HIV as planned in 2030.</p>
</sec>
<sec id="s2" sec-type="methods"><title>Methods</title>
<sec id="s2a"><title>Study setting</title>
<p>This study was conducted at health facilities in Gondar, Northwest Ethiopia. This town is located in the Amhara region 748&#x2005;km from Addis Ababa. It has one referral hospital that provides services for over 5 million people in the catchment area (<xref ref-type="bibr" rid="B39">39</xref>). The PMTCT program began on June 23, 2013, and since then 1,049 women with HIV were enrolled for PMTCT services and treatment through December 31, 2019.</p>
</sec>
<sec id="s2b"><title>Study design and population</title>
<p>This institution-based retrospective follow-up study was conducted among pregnant and lactating women in the Option B&#x002B; PMTCT program. Data were extracted from February to April 2020. Pregnant and lactating women in the PMTCT program from June 23, 2013, to December 31, 2019, were included in the study. The study included only pregnant and breastfeeding women who were enrolled in long-lasting ART PMTCT services for at least 3&#x2005;months before the end of data collection. We excluded patients with incomplete PMTCT record regarding maternal cohort outcomes and data inconsistencies regarding ART confirmation and initiation in the Option B&#x002B; program. A total of 403 pregnant and breastfeeding women&#x0027;s charts were reviewed after selection using simple random sampling from the PMTCT register based on the inclusion criteria.</p>
</sec>
<sec id="s2c"><title>Study variables and definitions</title>
<p>The outcome variable in this study was the incidence of LTFU in the Option B&#x002B; PMTCT program.</p>
<sec id="s2c1"><title>Operational definitions</title>
<p><bold>LTFU</bold> is defined as missing 90 days after the last documented visit as per recently developed simplified tools to measure retention in care in ART programs (<xref ref-type="bibr" rid="B40">40</xref>, <xref ref-type="bibr" rid="B41">41</xref>). <bold>Event:</bold> LTFU, which is 3 months after the last documented visit under Option B&#x002B; PMTCT and not recorded as &#x201C;dead,&#x201D; &#x201C;retained,&#x201D; or &#x201C;transferred-out&#x201D; on the patient&#x0027;s PMTCT logbook or medical cards (<xref ref-type="bibr" rid="B4">4</xref>). <bold>Censored:</bold> A patient did not develop an event or LTFU that could be death, transferred-out, treatment completed, or receiving treatment when the study ended.</p>
<p><bold>Time to LTFU:</bold> Time in months from the beginning of treatment under the Option B&#x002B; PMTCT program to LTFU under the program. <bold>Recent adherence level:</bold> Adherence was classified as good, fair, or poor, according to the percentage of drug dosage calculated from the monthly total dose of ART drugs. Describe as <bold>good</bold> (equal to or greater than 95&#x0025; or &#x2264;missing less than or equal to 2 out of 30 doses or missing 3 or less from the 60 doses), <bold>fair [(</bold>85&#x0025;&#x2013;94&#x0025;) adherence or missing 3&#x2013;5 doses out of 30 tabs or 3&#x2013;9 tablets from 60 doses], or <bold>poor</bold> (less than 85&#x0025; or missing &#x2265;6 tablets out of 30 tabs or &#x003E;9 tabs from 60 tabs) (<xref ref-type="bibr" rid="B42">42</xref>). The functional status of women was defined based on the WHO criteria as follows: <bold>Working</bold> is defined as the ability to perform usual work inside or outside the home. <bold>Ambulatory</bold>: able to perform activities of daily living. <bold>Bedridden</bold>: inability to perform activities of daily living (<xref ref-type="bibr" rid="B43">43</xref>).</p>
</sec>
</sec>
<sec id="s2d"><title>Data collection procedure and quality assurance</title>
<p>The data sources included the Federal Ministry of Health patient card, ART intake forms, HIV care follow-up, and the PMTCT register using a data extraction checklist. The components of the checklist are sociodemographic characteristics, immunologic, treatment, clinical, behavioral, follow-up, and outcome variables. Records of patients in the last 7&#x2005;years after the Option B&#x002B; program were extracted based on the inclusion criteria. Six data collectors and two supervisors were recruited to extract data from the PMTCT service records at the University of Gondar Comprehensive and Specialized Hospital. Data reviewers were trained with BSc midwives working in the PMTCT clinic. Data were extracted using a structured extraction tool prepared for the study. The data extraction checklist was prepared based on the information contained within the patient registration and follow-up cards, according to national guidelines.</p>
</sec>
<sec id="s2e"><title>Statistical analysis</title>
<p>After collecting the data, they were cleansed, coded, and entered into Epi Data version 4.6.0.0. They were then exported to STATA version 14 (StataCorp, College Station, TX, United States) for further analysis. The incidence rate was computed using person-month observations by adding the amount of time spent by study participants during the follow-up period. Kaplan&#x2013;Meier non-parametric survival analyses were performed to estimate the cumulative survival probability of LTFU at a specific time after the PMTCT program and the Nelson&#x2013;Aalen method was used to generate a cumulative hazard function. Univariate Cox proportional hazards were fitted to the predictors of LTFU among women in the Option B&#x002B; PMTCT program for complete data. Potential predictors signi&#xFB01;cantly associated with LTFU in the univariate models (<italic>p</italic>&#x2009;&#x003C;&#x2009;0.25) were evaluated using a multivariable model. To identify the combination of factors that best predicted LTFU, the backward stepwise Cox proportional hazards model evaluated the inclusion or exclusion of potential predictors at each step. The model with the highest log likelihood was chosen and checked for individual variation using a univariate frailty model. The proportional hazard assumption and fit of the model were checked using the Schoenfeld global test and Cox-Snell residual plot, respectively. Finally, results were reported as a hazard ratio with 95&#x0025; CI and examined at a significance level of <italic>p</italic>&#x2009;&#x003D;&#x2009;0.05 using a multivariable Cox proportional hazard model.</p>
</sec>
</sec>
<sec id="s3" sec-type="results"><title>Results</title>
<sec id="s3a"><title>Sociodemographic and maternal-related characteristics</title>
<p>The mean [&#x00B1; standard deviation (SD)] age of the mothers was 27.6&#x2009;&#x00B1;&#x2009;4.7&#x2005;years. Overall, 98 (24.3&#x0025;) women were aged 15&#x2013;24 years old. The majority of study participants 248 (61.5&#x0025;) were urban dwellers. A total of 186 participants (46.1&#x0025;) were housewives. Of the 403 observations, 359 (89.1&#x0025;) women were pregnant during ART treatment and 169 (41.9&#x0025;) were newly enrolled in ART treatment. Approximately 70 (17.4&#x0025;) women had a mid-upper arm circumference (MUAC) (&#x003C;23&#x2005;cm) level. Overall, 222 (55.1&#x0025;) of the partners were positive for HIV (<xref ref-type="table" rid="T1">Table&#x00A0;1</xref>).</p>
<table-wrap id="T1" position="float"><label>Table 1</label>
<caption><p>Baseline sociodemographic, maternal-related characteristics of pregnant and breastfeeding women on Option B&#x002B; from June 2013 to December 2019 in Northwest Ethiopia (<italic>n</italic>&#x2009;&#x003D;&#x2009;403).</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="left"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left">Variables</th>
<th valign="top" align="center">Category</th>
<th valign="top" align="center">Frequency (<xref ref-type="bibr" rid="B41">41</xref>)</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left" rowspan="4">Age in years</td>
<td valign="top" align="left">Mean&#x2009;&#x00B1;&#x2009;SD</td>
<td valign="top" align="center">27.6&#x2009;&#x00B1;&#x2009;4.7</td>
</tr>
<tr>
<td valign="top" align="left">15&#x2013;24</td>
<td valign="top" align="center">98 (24.3)</td>
</tr>
<tr>
<td valign="top" align="left">25&#x2013;29</td>
<td valign="top" align="center">160 (39.7)</td>
</tr>
<tr>
<td valign="top" align="left">30&#x2013;45</td>
<td valign="top" align="center">145 (36.0)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Place of residence</td>
<td valign="top" align="left">Urban</td>
<td valign="top" align="center">248 (61.5)</td>
</tr>
<tr>
<td valign="top" align="left">Rural</td>
<td valign="top" align="center">155 (38.5)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="4">Marital status</td>
<td valign="top" align="left">Single</td>
<td valign="top" align="center">53 (13.2)</td>
</tr>
<tr>
<td valign="top" align="left">Married</td>
<td valign="top" align="center">264 (65.5)</td>
</tr>
<tr>
<td valign="top" align="left">Widowed</td>
<td valign="top" align="center">33 (8.1)</td>
</tr>
<tr>
<td valign="top" align="left">Divorced</td>
<td valign="top" align="center">53 (13.2)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">Religion</td>
<td valign="top" align="left">Orthodox Christian</td>
<td valign="top" align="center">328 (81.4)</td>
</tr>
<tr>
<td valign="top" align="left">Muslim</td>
<td valign="top" align="center">49 (12.2)</td>
</tr>
<tr>
<td valign="top" align="left">Others (protestant, catholic)</td>
<td valign="top" align="center">26 (6.4)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="4">Educational status</td>
<td valign="top" align="left">No education</td>
<td valign="top" align="center">126 (31.3)</td>
</tr>
<tr>
<td valign="top" align="left">Primary</td>
<td valign="top" align="center">112 (27.8)</td>
</tr>
<tr>
<td valign="top" align="left">Secondary</td>
<td valign="top" align="center">110 (27.3)</td>
</tr>
<tr>
<td valign="top" align="left">Above secondary</td>
<td valign="top" align="center">55 (13.6)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="5">Occupational status</td>
<td valign="top" align="left">Housewife</td>
<td valign="top" align="center">186 (46.1)</td>
</tr>
<tr>
<td valign="top" align="left">Governmental employee</td>
<td valign="top" align="center">62 (15.4)</td>
</tr>
<tr>
<td valign="top" align="left">No-governmental employee</td>
<td valign="top" align="center">23 (5.7)</td>
</tr>
<tr>
<td valign="top" align="left">Daily laborer</td>
<td valign="top" align="center">99 (24.6)</td>
</tr>
<tr>
<td valign="top" align="left">Others<xref ref-type="table-fn" rid="table-fn1"><sup>a</sup></xref></td>
<td valign="top" align="center">33 (8.2)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Number of pregnancies</td>
<td valign="top" align="left">One</td>
<td valign="top" align="center">147 (36.5)</td>
</tr>
<tr>
<td valign="top" align="left">Multiple</td>
<td valign="top" align="center">256 (63.5)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Enrolment Status of women</td>
<td valign="top" align="left">Pregnancy</td>
<td valign="top" align="center">359 (89.1)</td>
</tr>
<tr>
<td valign="top" align="left">Breastfeeding</td>
<td valign="top" align="center">44 (10.9)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Enrolment type to PMTCT</td>
<td valign="top" align="left">New</td>
<td valign="top" align="center">169 (41.9)</td>
</tr>
<tr>
<td valign="top" align="left">On ART before enrolment</td>
<td valign="top" align="center">234 (58.1)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Recent MUAC level</td>
<td valign="top" align="left">&#x2265;23&#x2005;cm</td>
<td valign="top" align="center">333 (82.6)</td>
</tr>
<tr>
<td valign="top" align="left">&#x003C;23&#x2005;cm</td>
<td valign="top" align="center">70 (17.4)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">Partner HIV status</td>
<td valign="top" align="left">Positive</td>
<td valign="top" align="center">222 (55.1)</td>
</tr>
<tr>
<td valign="top" align="left">Negative</td>
<td valign="top" align="center">131 (32.5)</td>
</tr>
<tr>
<td valign="top" align="left">Unknown/not done</td>
<td valign="top" align="center">50 (12.4)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Disclosure status</td>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">315 (78.2)</td>
</tr>
<tr>
<td valign="top" align="left">No</td>
<td valign="top" align="center">88 (21.8)</td>
</tr>
<tr>
<td valign="top" align="left">Total</td>
<td valign="top" align="left"/>
<td valign="top" align="center">403 (100.0&#x0025;)</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table-fn1"><label><sup>a</sup></label><p>Others: student and merchant.</p></fn>
</table-wrap-foot>
</table-wrap>
</sec>
<sec id="s3b"><title>Clinical, laboratory, and treatment-related characteristics</title>
<p>The mean&#x2009;&#x00B1;&#x2009;SD of CD4 was 419.1&#x2009;&#x00B1;&#x2009;224.0&#x2005;cells/ml<sup>3</sup> with a CD4 count greater than 350&#x2005;cells/mm<sup>3</sup> of 238 (59.1&#x0025;) at baseline. Of the total study participants, 344 (85.4&#x0025;) were classified as WHO clinical stage one followed by WHO clinical stage two 37(9.2). The combination therapy <italic>AZT-3TC-EFV</italic> was the second predominant regimen prescribed during enrolment for 105 (26.1&#x0025;) women, followed by <italic>TDF-3TC-EFV</italic> for 239 (59.3&#x0025;). Overall, 132 (32.8&#x0025;) women were anemic during enrolment. The majority (83.6&#x0025;) of the women had good adherence levels, and 72 (17.9&#x0025;) developed ART treatment-related side effects during PMTCT enrolment. Overall, 279 (69.9&#x0025;) women had at least one recorded viral load measurement within 3&#x2005;months of PMTCT enrolment (<xref ref-type="table" rid="T2">Table&#x00A0;2</xref>).</p>
<table-wrap id="T2" position="float"><label>Table 2</label>
<caption><p>Clinical, laboratory, and treatment-related characteristics of pregnant and breastfeeding women on Option B&#x002B; from June 2013 to December 2019, Northwest Ethiopia.</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="left"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left">Variables</th>
<th valign="top" align="center">Category</th>
<th valign="top" align="center">Frequency (<xref ref-type="bibr" rid="B41">41</xref>)</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left" rowspan="2">TB screening status</td>
<td valign="top" align="left">Negative</td>
<td valign="top" align="center">379 (94.0)</td>
</tr>
<tr>
<td valign="top" align="left">Positive</td>
<td valign="top" align="center">24 (6.0)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">INH prophylaxis</td>
<td valign="top" align="left">No</td>
<td valign="top" align="center">351 (87.1)</td>
</tr>
<tr>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">52 (12.9)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Comorbidity</td>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">27 (6.7)</td>
</tr>
<tr>
<td valign="top" align="left">No</td>
<td valign="top" align="center">376 (93.3)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="5">Initial ART regimen</td>
<td valign="top" align="left"><italic>AZT-3TC-NVP</italic></td>
<td valign="top" align="center">105 (26.1)</td>
</tr>
<tr>
<td valign="top" align="left"><italic>AZT-3TC-EFV</italic></td>
<td valign="top" align="center">29 (7.2)</td>
</tr>
<tr>
<td valign="top" align="left"><italic>TDF-3TC-EFV</italic></td>
<td valign="top" align="center">239 (59.3)</td>
</tr>
<tr>
<td valign="top" align="left"><italic>TDF-FTC-NVP</italic></td>
<td valign="top" align="center">22 (5.4)</td>
</tr>
<tr>
<td valign="top" align="left">Others</td>
<td valign="top" align="center">8 (2.0)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Change of ART regimen</td>
<td valign="top" align="left">No</td>
<td valign="top" align="center">344 (85.4)</td>
</tr>
<tr>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">59 (14.6)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Anemia status</td>
<td valign="top" align="left">Not anemic</td>
<td valign="top" align="center">271 (67.2)</td>
</tr>
<tr>
<td valign="top" align="left">Anemic</td>
<td valign="top" align="center">132 (32.8)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Adherence level</td>
<td valign="top" align="left">Good</td>
<td valign="top" align="center">337 (83.6)</td>
</tr>
<tr>
<td valign="top" align="left">Fair/Poor</td>
<td valign="top" align="center">66 (16.4)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Maternal CPT</td>
<td valign="top" align="left">No</td>
<td valign="top" align="center">223 (53.3)</td>
</tr>
<tr>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">180 (44.7)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Drug side effects</td>
<td valign="top" align="left">No</td>
<td valign="top" align="center">331 (82.1)</td>
</tr>
<tr>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">72 (17.9)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">WHO clinical stage</td>
<td valign="top" align="left">Early stage (I/II)</td>
<td valign="top" align="center">381 (94.6)</td>
</tr>
<tr>
<td valign="top" align="left">Late stage (III/IV)</td>
<td valign="top" align="center">22 (5.4)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Functional status</td>
<td valign="top" align="left">Working</td>
<td valign="top" align="center">355 (88.1)</td>
</tr>
<tr>
<td valign="top" align="left">Ambulatory/bedridden</td>
<td valign="top" align="center">48 (11.9)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Time of ART initiation</td>
<td valign="top" align="left">Later</td>
<td valign="top" align="center">144 (35.7)</td>
</tr>
<tr>
<td valign="top" align="left">Same day</td>
<td valign="top" align="center">259 (64.3)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="4">CD4 cell count (cells/mm<sup>3</sup>)</td>
<td valign="top" align="left">Mean&#x2009;&#x00B1;&#x2009;SD</td>
<td valign="top" align="center">419.1&#x2009;&#x00B1;&#x2009;224.0</td>
</tr>
<tr>
<td valign="top" align="left">Less than 200</td>
<td valign="top" align="center">60 (14.9)</td>
</tr>
<tr>
<td valign="top" align="left">200&#x2013;350</td>
<td valign="top" align="center">105 (26.1)</td>
</tr>
<tr>
<td valign="top" align="left">Greater than 350</td>
<td valign="top" align="center">238 (59.1)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Baseline viral load taken</td>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">279 (69.2)</td>
</tr>
<tr>
<td valign="top" align="left">No</td>
<td valign="top" align="center">124 (30.8)</td>
</tr>
<tr>
<td valign="top" align="left">Total</td>
<td valign="top" align="left"/>
<td valign="top" align="center">403 (100.0&#x0025;)</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table-fn2"><p>CPT, co-trimoxazole preventive therapy; AZT, Zidovudine; 3TC, Lamivudine&#x2009;&#x003D;&#x2009;Nevirapine; EFV, Efavirenz&#x2009;&#x003D;&#x2009;Tenofovir Disoproxil Fumarate; FTC, Emtricitabine; Others, 1&#x2005;g (ABC&#x2009;&#x002B;&#x2009;3TC&#x2009;&#x002B;&#x2009;NVP), 2f (AZT-3TC-ATV/r), second-line treatment; TB, Tuberculosis; INH, Isoniazid; Comorbidity, heart disease and/or renal diseases and/or hypertension, and/or diabetes mellitus.</p></fn>
</table-wrap-foot>
</table-wrap>
</sec>
<sec id="s3c"><title>Maternal PMTCT cohort outcome of the study</title>
<sec id="s3c1"><title>Survival status of study participants</title>
<p>Overall, 6.8&#x0025; (95&#x0025; CI: 13.5&#x2013;20.8) of women were LTFU to ART treatment by completing the PMTCT program, and five (1.2&#x0025;) women died during ART treatment of PMTCT. About 403 study participants were followed for a mean&#x2009;&#x00B1;&#x2009;SD time of 17.9 (&#x00B1;7.2)&#x2005;months. Of the total observations, 12 (2.9&#x0025;), 31 (7.7&#x0025;), 53 (13.2&#x0025;), and 68 (16.8&#x0025;) women were LTFU at the end of 6, 12, 18, and end months of the PMTCT program, respectively. Three hundred and thirty-five (83.1&#x0025;) observations were censored (retained, transferred out, or died) at the end of the enrolment (<xref ref-type="fig" rid="F1">Figure&#x00A0;1</xref>).</p>
<fig id="F1" position="float"><label>Figure 1</label>
<caption><p>Consort diagram with total number of eligible patients and final number of women included in the analysis.</p></caption>
<graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="fgwh-04-1128988-g001.tif"/>
</fig>
</sec>
<sec id="s3c2"><title>Incidence rate of LTFU</title>
<p>We calculated the incidence rate by taking the denominator as PM because the study was a dynamic cohort. During the follow-up period, a total of 7,215 person-months&#x2019; time risk was observed with an overall incidence rate of LTFU 9.4/1,000 person-months (95&#x0025; CI: 7.4&#x2013;11.9) by the end of PMTCT follow-up. The incidence proportion of LTFU was dramatically declining from the initiation of the program in 2013 from 38&#x0025; to 6.8&#x0025; in 2019 (<xref ref-type="fig" rid="F2">Figure&#x00A0;2</xref>).</p>
<fig id="F2" position="float"><label>Figure 2</label>
<caption><p>Incidence of LTFU by enrolment year among pregnant and breastfeeding women on Option B&#x002B; PMTCT program from June 2013&#x2013;December 2019 in Northwest Ethiopia.</p></caption>
<graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="fgwh-04-1128988-g002.tif"/>
</fig>
<p>The Kaplan&#x2013;Meier method for the time to LTFU after ART initiation during the PMTCT follow-up period showed that close to 80&#x0025; of the participants were still in care after 12 months of follow-up (<xref ref-type="fig" rid="F3">Figure&#x00A0;3</xref>). The cumulative hazard estimate of LTFU showed a difference in the enrolment status of the PMTCT program. The cumulative hazard of LTFU among HIV-positive lactating women was higher than pregnant women during PMTCT enrolment (<xref ref-type="fig" rid="F4">Figure&#x00A0;4</xref>).</p>
<fig id="F3" position="float"><label>Figure 3</label>
<caption><p>Kaplan&#x2013;Meier survival estimate of LTFU among pregnant and breastfeeding women on Option B&#x002B; PMTCT program from June 2013&#x2013;December 2019 in Northwest Ethiopia.</p></caption>
<graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="fgwh-04-1128988-g003.tif"/>
</fig>
<fig id="F4" position="float"><label>Figure 4</label>
<caption><p>Cumulative hazard estimate of LTFU among pregnant and breastfeeding women on Option B&#x002B; PMTCT program by from June 2013&#x2013;December 2019 in Northwest Ethiopia by enrolment status.</p></caption>
<graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="fgwh-04-1128988-g004.tif"/>
</fig>
</sec>
<sec id="s3c3"><title>Incidence of LTFU among different levels of predictor variables</title>
<p>Overall, the incidence rate was higher for women residing in rural areas (19.3 per 1,000 person-months) and lower for mothers residing in urban areas (4.1 per 1,000 person-months). The l-rank test also showed that women had a significant difference in LTFU between the rural and urban areas. Moreover, it shows that the incidence of LTFU was significantly different according to the patient&#x0027;s marital status, religion, status of women during enrolment, enrolment type, MUAC level, anemia status, adherence level, CD4 cell count, ART initiation time, drug side effects, and baseline viral load so that these variables were included in the binary cox regression (<xref ref-type="table" rid="T3">Table&#x00A0;3</xref>).</p>
<table-wrap id="T3" position="float"><label>Table 3</label>
<caption><p>Comparisons of LTFU among different levels of baseline predictor variables using a log-rank test from pregnant and breastfeeding women on Option B&#x002B; PMTCT program in Northwest Ethiopia (June 2013&#x2013;December 2019).</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="left"/>
<col align="center"/>
<col align="center"/>
<col align="center"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left" rowspan="2">Variables</th>
<th valign="top" align="center" rowspan="2">Category</th>
<th valign="top" align="center" colspan="2">LTFU</th>
<th valign="top" align="center" colspan="2">Log-rank test</th>
</tr>
<tr>
<th valign="top" align="center">IR/1,000</th>
<th valign="top" align="center">PMO</th>
<th valign="top" align="center"><italic>X</italic><sup>2</sup></th>
<th valign="top" align="center"><italic>p-</italic>value</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left" rowspan="3">Age in years</td>
<td valign="top">15&#x2013;24</td>
<td valign="top">7.9</td>
<td valign="top">1,780</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">25&#x2013;29</td>
<td valign="top">9.2</td>
<td valign="top">2,818</td>
<td valign="top">0.84</td>
<td valign="top">0.6580</td>
</tr>
<tr>
<td valign="top">30&#x2013;45</td>
<td valign="top">10.7</td>
<td valign="top">2,617</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Place of residence</td>
<td valign="top">Urban</td>
<td valign="top">4.1</td>
<td valign="top">4,675</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Rural</td>
<td valign="top">19.3</td>
<td valign="top">2,540</td>
<td valign="top">40.98</td>
<td valign="top">&#x003C;0.0001</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">Marital status</td>
<td valign="top">Single</td>
<td valign="top">21.5</td>
<td valign="top">838</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Married</td>
<td valign="top">7.2</td>
<td valign="top">4,866</td>
<td valign="top">17.11</td>
<td valign="top">0.0002</td>
</tr>
<tr>
<td valign="top">Widowed/divorced</td>
<td valign="top">9.9</td>
<td valign="top">1,511</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">Religion</td>
<td valign="top">Orthodox Christian</td>
<td valign="top">7.8</td>
<td valign="top">6,002</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Muslim</td>
<td valign="top">19.5</td>
<td valign="top">718</td>
<td valign="top">10.93</td>
<td valign="top">0.0042</td>
</tr>
<tr>
<td valign="top">Others<xref ref-type="table-fn" rid="table-fn5"><sup>a</sup></xref></td>
<td valign="top">14.1</td>
<td valign="top">495</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top" align="left" rowspan="4">Educational status</td>
<td valign="top">No education</td>
<td valign="top">13.1</td>
<td valign="top">2,139</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Primary</td>
<td valign="top">7.3</td>
<td valign="top">2,057</td>
<td valign="top">4.26</td>
<td valign="top">0.2350</td>
</tr>
<tr>
<td valign="top">Secondary</td>
<td valign="top">8.1</td>
<td valign="top">1,985</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Above</td>
<td valign="top">8.7</td>
<td valign="top">1,034</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top" align="left" rowspan="5">Employment status</td>
<td valign="top">Housewife</td>
<td valign="top">7.8</td>
<td valign="top">3,322</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Government employee</td>
<td valign="top">9.8</td>
<td valign="top">1,120</td>
<td valign="top">5.74</td>
<td valign="top">0.2190</td>
</tr>
<tr>
<td valign="top">Non-government employee</td>
<td valign="top">19.8</td>
<td valign="top">405</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Daily laborer</td>
<td valign="top">9.5</td>
<td valign="top">1,789</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Others<xref ref-type="table-fn" rid="table-fn5"><sup>a</sup></xref></td>
<td valign="top">10.4</td>
<td valign="top">579</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Number of pregnancies</td>
<td valign="top">Single</td>
<td valign="top">9.8</td>
<td valign="top">2,637</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Multiple</td>
<td valign="top">9.2</td>
<td valign="top">4,578</td>
<td valign="top">0.11</td>
<td valign="top">0.7418</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">Partner HIV status</td>
<td valign="top">Positive</td>
<td valign="top">8.6</td>
<td valign="top">4,074</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Negative</td>
<td valign="top">7.3</td>
<td valign="top">2,326</td>
<td valign="top">10.61</td>
<td valign="top">0.0050</td>
</tr>
<tr>
<td valign="top">Unknown/not done</td>
<td valign="top">19.6</td>
<td valign="top">815</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Disclosure status</td>
<td valign="top">Yes</td>
<td valign="top">6.9</td>
<td valign="top">5,730</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">No</td>
<td valign="top">18.9</td>
<td valign="top">1,485</td>
<td valign="top">17.49</td>
<td valign="top">&#x003C;0.0001</td>
</tr>
<tr>
<td valign="top" rowspan="2">Enrolment status</td>
<td valign="top">Pregnancy</td>
<td valign="top">8.4</td>
<td valign="top">6,647</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Breastfeeding</td>
<td valign="top">21.1</td>
<td valign="top">568</td>
<td valign="top">8.05</td>
<td valign="top">0.0046</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Enrolment type</td>
<td valign="top">New</td>
<td valign="top">13.7</td>
<td valign="top">2,698</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">On ART before enrolment</td>
<td valign="top">6.8</td>
<td valign="top">4,517</td>
<td valign="top">8.44</td>
<td valign="top">0.0037</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Comorbidity</td>
<td valign="top">No</td>
<td valign="top">8.0</td>
<td valign="top">6,488</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Yes</td>
<td valign="top">22.2</td>
<td valign="top">727</td>
<td valign="top">13.51</td>
<td valign="top">0.0002</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">MUAC level</td>
<td valign="top">&#x2265;23&#x2005;cm</td>
<td valign="top">5.6</td>
<td valign="top">6,203</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">&#x003C;23&#x2005;cm</td>
<td valign="top">32.6</td>
<td valign="top">1,012</td>
<td valign="top">67.16</td>
<td valign="top">&#x003C;0.0001</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Anemia status</td>
<td valign="top">Not anemic</td>
<td valign="top">4.3</td>
<td valign="top">5,128</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Anemic</td>
<td valign="top">22.0</td>
<td valign="top">2,087</td>
<td valign="top">48.56</td>
<td valign="top">&#x003C;0.0001</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Maternal CPT</td>
<td valign="top">No</td>
<td valign="top">4.5</td>
<td valign="top">4,017</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Yes</td>
<td valign="top">15.6</td>
<td valign="top">3,198</td>
<td valign="top">23.81</td>
<td valign="top">&#x003C;0.0001</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="4">Initial ART regimen</td>
<td valign="top"><italic>AZT-3TC-NVP</italic></td>
<td valign="top">10.3</td>
<td valign="top">1,933</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top"><italic>AZT-3TC-EFV</italic></td>
<td valign="top">5.2</td>
<td valign="top">582</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top"><italic>TDF-3TC-EFV</italic></td>
<td valign="top">10.5</td>
<td valign="top">4,091</td>
<td valign="top">4.58</td>
<td valign="top">0.2050</td>
</tr>
<tr>
<td valign="top">Other</td>
<td valign="top">3.3</td>
<td valign="top">609</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">WHO clinical stage</td>
<td valign="top">Early stage(I/II)</td>
<td valign="top">8.5</td>
<td valign="top">6,908</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Late stage (III/IV)</td>
<td valign="top">29.3</td>
<td valign="top">307</td>
<td valign="top">13.06</td>
<td valign="top">0.0003</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Functional status</td>
<td valign="top">Working</td>
<td valign="top">7.2</td>
<td valign="top">6,538</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Ambulatory/bedridden</td>
<td valign="top">31.0</td>
<td valign="top">677</td>
<td valign="top">37.27</td>
<td valign="top">&#x003C;0.0001</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Adherence level</td>
<td valign="top">Good</td>
<td valign="top">4.4</td>
<td valign="top">6,310</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Fair/Poor</td>
<td valign="top">44.2</td>
<td valign="top">905</td>
<td valign="top">134.86</td>
<td valign="top">&#x003C;0.0001</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">CD4 cell count in cells/ml</td>
<td valign="top">&#x003E;350</td>
<td valign="top">6.0</td>
<td valign="top">4,340</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">200&#x2013;350</td>
<td valign="top">7.8</td>
<td valign="top">1,917</td>
<td valign="top">14.69</td>
<td valign="top">0.0001</td>
</tr>
<tr>
<td valign="top">&#x003C;200</td>
<td valign="top">28.2</td>
<td valign="top">958</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">ART initiation time</td>
<td valign="top">Same day</td>
<td valign="top">11.5</td>
<td valign="top">4,707</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Latter</td>
<td valign="top">5.6</td>
<td valign="top">2,508</td>
<td valign="top">5.86</td>
<td valign="top">0.0155</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">ART side effects</td>
<td valign="top">No</td>
<td valign="top">5.1</td>
<td valign="top">6,104</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">Yes</td>
<td valign="top">33.3</td>
<td valign="top">1,111</td>
<td valign="top">79.40</td>
<td valign="top">&#x003C;0.0001</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Baseline viral load taken</td>
<td valign="top">Yes</td>
<td valign="top">3.1</td>
<td valign="top">5,196</td>
<td valign="top"/>
<td valign="top"/>
</tr>
<tr>
<td valign="top">No</td>
<td valign="top">25.8</td>
<td valign="top">2,019</td>
<td valign="top">79.00</td>
<td valign="top">&#x003C;0.00001</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table-fn3"><p>IR, incidence rate of loss to follow-up; PMO, person-month observation.</p></fn>
<fn id="table-fn4"><p>Comorbidity included chronic illness, tuberculosis, and opportunistic infections.</p></fn>
<fn id="table-fn5"><label><sup>a</sup></label><p>Others: student and merchant.</p></fn>
</table-wrap-foot>
</table-wrap>
</sec>
</sec>
<sec id="s3d"><title>Factors affecting loss to follow-up from PMTCT service</title>
<p>Predictors included in the multivariable Cox regression analysis were those with a <italic>p</italic>-value &#x003C;0.25 in the bivariable analysis, and 21 variables were selected in the first step of model building. After running backward stepwise variable selection and considering multicollinearity, the first group was selected as the best model from the likelihood ratio, which included full (<xref ref-type="bibr" rid="B17">17</xref>) variables in the multivariable analysis.</p>
<p>According to the multivariable Cox regression analysis, rural residents were at a 2.30 higher risk of LTFU (AHR: 2.30; 95&#x0025; CI: 1.08&#x2013;4.88) as compared to urban residents. Muslim religious followers were at 2.44 times higher risk of LTFU (AHR: 2.44; 95&#x0025; CI: 1.23&#x2013;4.81) as compared to Orthodox Christian religious followers. The risk of LTFU for participants who started ART on the same day as HIV diagnosis was 3.23 times more likely than the latter initiation (AHR: 3.23; 95&#x0025; CI: 1.53&#x2013;6.84). Participants who were on ART before PMTCT enrolment had a 70&#x0025; increased risk of LTFU compared with newly enrolled patients (AHR: 0.30; 95&#x0025; CI: 0.15&#x2013;0.62). During the last PMTCT follow-up, LTFU among participants who had drug side effects was 82&#x0025; higher than that among their counterparts (AHR: 1.82; 95&#x0025; CI: 1.01&#x2013;3.33). Participants with suboptimal adherence status (fair/poor) had a 3.96 times higher risk of LTFU (AHR: 3.96; 95&#x0025; CI: 2.18&#x2013;7.19) than participants with good adherence. Finally, the risk of LTFU among women who had no viral load measurement was 4.21 times higher than those who had viral load measurement during enrolment (AHR: 4.21; 95&#x0025; CI: 2.23&#x2013;7.96) (<xref ref-type="table" rid="T4">Table&#x00A0;4</xref>). The global test results showed <italic>p</italic>&#x2009;&#x003E;&#x2009;0.05; thus, we did not violate the proportional assumption.</p>
<table-wrap id="T4" position="float"><label>Table 4</label>
<caption><p>Multivariable Cox regression of LTFU among pregnant and breastfeeding women on Option B&#x002B; PMTCT program from June 2013&#x2013;December 2019 in Northwest Ethiopia.</p></caption>
<table frame="hsides" rules="groups">
<colgroup>
<col align="left"/>
<col align="left"/>
<col align="center"/>
<col align="center"/>
<col align="center"/>
<col align="center"/>
</colgroup>
<thead>
<tr>
<th valign="top" align="left" rowspan="2" colspan="2">Variables</th>
<th valign="top" align="center" rowspan="2">Censored</th>
<th valign="top" align="center" rowspan="2">LTFU</th>
<th valign="top" align="center">Crude hazard ratio</th>
<th valign="top" align="center">Adjusted hazard ratio</th>
</tr>
<tr>
<th valign="top" align="center">CHR (95&#x0025; CI)</th>
<th valign="top" align="center">AHR (95&#x0025; CI)</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="top" align="left" rowspan="2">Residence</td>
<td valign="top" align="left">Urban</td>
<td valign="top" align="center">229</td>
<td valign="top" align="center">19</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Rural</td>
<td valign="top" align="center">106</td>
<td valign="top" align="center">49</td>
<td valign="top" align="center">4.75 (2.79&#x2013;8.07)</td>
<td valign="top" align="center">2.30 (1.08&#x2013;4.88) <xref ref-type="table-fn" rid="table-fn7">&#x002A;</xref></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">Religion</td>
<td valign="top" align="left">Orthodox</td>
<td valign="top" align="center">281</td>
<td valign="top" align="center">47</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Muslim</td>
<td valign="top" align="center">35</td>
<td valign="top" align="center">14</td>
<td valign="top" align="center">2.52 (1.38&#x2013;4.57)</td>
<td valign="top" align="center">2.44 (1.23&#x2013;4.81)<xref ref-type="table-fn" rid="table-fn7">&#x002A;</xref></td>
</tr>
<tr>
<td valign="top" align="left">Others<xref ref-type="table-fn" rid="table-fn6"><sup>a</sup></xref></td>
<td valign="top" align="center">19</td>
<td valign="top" align="center">7</td>
<td valign="top" align="center">1.84 (0.83&#x2013;4.07)</td>
<td valign="top" align="center">2.33 (0.87&#x2013;6.21)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">Marital status</td>
<td valign="top" align="left">Married</td>
<td valign="top" align="center">229</td>
<td valign="top" align="center">35</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Single</td>
<td valign="top" align="center">35</td>
<td valign="top" align="center">18</td>
<td valign="top" align="center">3.12 (1.77&#x2013;5.52)</td>
<td valign="top" align="center">1.57 (0.76&#x2013;3.23)</td>
</tr>
<tr>
<td valign="top" align="left">Divorced/widowed</td>
<td valign="top" align="center">71</td>
<td valign="top" align="center">15</td>
<td valign="top" align="center">1.38 (0.76&#x2013;2.53)</td>
<td valign="top" align="center">0.77 (0.36&#x2013;1.65)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Disclosure status</td>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">275</td>
<td valign="top" align="center">40</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">No</td>
<td valign="top" align="center">60</td>
<td valign="top" align="center">28</td>
<td valign="top" align="center">2.67 (1.65&#x2013;4.34)</td>
<td valign="top" align="center">0.91 (0.47&#x2013;1.81)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">ART initiation time</td>
<td valign="top" align="left">Latter</td>
<td valign="top" align="center">130</td>
<td valign="top" align="center">14</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Same day</td>
<td valign="top" align="center">205</td>
<td valign="top" align="center">54</td>
<td valign="top" align="center">2.02 (1.12&#x2013;3.65)</td>
<td valign="top" align="center">3.23 (1.53&#x2013;6.84)<xref ref-type="table-fn" rid="table-fn7">&#x002A;</xref></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Comorbidity</td>
<td valign="top" align="left">No</td>
<td valign="top" align="center">307</td>
<td valign="top" align="center">52</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">28</td>
<td valign="top" align="center">16</td>
<td valign="top" align="center">2.72 (1.55&#x2013;4.77)</td>
<td valign="top" align="center">0.77 (0.37&#x2013;1.59)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">MUAC level</td>
<td valign="top" align="left">Greater or equal to 23&#x2005;cm</td>
<td valign="top" align="center">298</td>
<td valign="top" align="center">35</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Less than 23&#x2005;cm</td>
<td valign="top" align="center">37</td>
<td valign="top" align="center">33</td>
<td valign="top" align="center">5.78 (3.58&#x2013;9.33)</td>
<td valign="top" align="center">1.79 (0.91&#x2013;3.52)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Anemia status</td>
<td valign="top" align="left">Not anemic</td>
<td valign="top" align="center">249</td>
<td valign="top" align="center">22</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Anemic</td>
<td valign="top" align="center">86</td>
<td valign="top" align="center">46</td>
<td valign="top" align="center">5.04 (3.03&#x2013;8.39)</td>
<td valign="top" align="center">1.78 (0.97&#x2013;3.26)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Clinical stage</td>
<td valign="top" align="left">Early stage (I/II)</td>
<td valign="top" align="center">322</td>
<td valign="top" align="center">59</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Late stage (III/IV)</td>
<td valign="top" align="center">13</td>
<td valign="top" align="center">9</td>
<td valign="top" align="center">3.35 (1.66&#x2013;6.78)</td>
<td valign="top" align="center">0.87 (0.33&#x2013;2.3</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Functional status</td>
<td valign="top" align="left">Working</td>
<td valign="top" align="center">308</td>
<td valign="top" align="center">47</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Ambulatory/bedridden</td>
<td valign="top" align="center">27</td>
<td valign="top" align="center">21</td>
<td valign="top" align="center">4.33 (2.58&#x2013;7.26)</td>
<td valign="top" align="center">1.51 (0.63&#x2013;3.61)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Maternal CPT</td>
<td valign="top" align="left">No</td>
<td valign="top" align="center">205</td>
<td valign="top" align="center">18</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">130</td>
<td valign="top" align="center">50</td>
<td valign="top" align="center">3.49 (2.03&#x2013;5.98)</td>
<td valign="top" align="center">1.84 (0.95&#x2013;3.58)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Enrolment status</td>
<td valign="top" align="left">Pregnancy</td>
<td valign="top" align="center">303</td>
<td valign="top" align="center">56</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Breastfeeding</td>
<td valign="top" align="center">32</td>
<td valign="top" align="center">12</td>
<td valign="top" align="center">2.39 (1.28&#x2013;4.49)</td>
<td valign="top" align="center">0.97 (0.95&#x2013;2.25)</td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Enrolment type</td>
<td valign="top" align="left">New</td>
<td valign="top" align="center">132</td>
<td valign="top" align="center">37</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">On ART before enrolment</td>
<td valign="top" align="center">203</td>
<td valign="top" align="center">31</td>
<td valign="top" align="center">0.50 (0.31&#x2013;0.81)</td>
<td valign="top" align="center">0.30 (0.15&#x2013;0.62)<xref ref-type="table-fn" rid="table-fn8">&#x002A;&#x002A;</xref></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Side effects</td>
<td valign="top" align="left">No</td>
<td valign="top" align="center">300</td>
<td valign="top" align="center">31</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">35</td>
<td valign="top" align="center">37</td>
<td valign="top" align="center">6.52 (4.04&#x2013;10.52)</td>
<td valign="top" align="center">1.82 (1.01&#x2013;3.33) <xref ref-type="table-fn" rid="table-fn7">&#x002A;</xref></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">ART adherence level</td>
<td valign="top" align="left">Good</td>
<td valign="top" align="center">309</td>
<td valign="top" align="center">28</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">Fair/poor</td>
<td valign="top" align="center">26</td>
<td valign="top" align="center">40</td>
<td valign="top" align="center">10.19 (6.26&#x2013;16.58)</td>
<td valign="top" align="center">3.96 (2.18&#x2013;7.19)<xref ref-type="table-fn" rid="table-fn9">&#x002A;&#x002A;&#x002A;</xref></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="2">Baseline Viral load taken</td>
<td valign="top" align="left">Yes</td>
<td valign="top" align="center">263</td>
<td valign="top" align="center">16</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">No</td>
<td valign="top" align="center">72</td>
<td valign="top" align="center">52</td>
<td valign="top" align="center">8.29 (4.73&#x2013;14.52)</td>
<td valign="top" align="center">4.21 (2.23&#x2013;7.96)<xref ref-type="table-fn" rid="table-fn9">&#x002A;&#x002A;&#x002A;</xref></td>
</tr>
<tr>
<td valign="top" align="left" rowspan="3">Baseline CD4 cell count</td>
<td valign="top" align="left">&#x003C;200</td>
<td valign="top" align="center">33</td>
<td valign="top" align="center">27</td>
<td valign="top" align="center">1</td>
<td valign="top" align="center">1</td>
</tr>
<tr>
<td valign="top" align="left">200&#x2013;350</td>
<td valign="top" align="center">90</td>
<td valign="top" align="center">15</td>
<td valign="top" align="center">0.28 (0.15&#x2013;0.54)</td>
<td valign="top" align="center">1.19 (0.50&#x2013;2.83)</td>
</tr>
<tr>
<td valign="top" align="left">&#x003E;350</td>
<td valign="top" align="center">212</td>
<td valign="top" align="center">26</td>
<td valign="top" align="center">0.22 (0.13&#x2013;0.37)</td>
<td valign="top" align="center">1.53 (0.67&#x2013;3.49)</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="table-fn6"><label><sup>a</sup></label><p>Others: protestant and Catholic religions.</p></fn>
<fn id="table-fn7"><label>&#x002A;</label><p>Significant at <italic>p-</italic>value 0.05.</p></fn>
<fn id="table-fn8"><label>&#x002A;&#x002A;</label><p>Significant at <italic>p-</italic>value 0.01.</p></fn>
<fn id="table-fn9"><label>&#x002A;&#x002A;&#x002A;</label><p>Significant at <italic>p-</italic>value 0.001.</p></fn>
</table-wrap-foot>
</table-wrap>
</sec>
</sec>
<sec id="s4" sec-type="discussion"><title>Discussion</title>
<p>Loss to follow-up is a major challenge in PMTCT programs, which leads to the advanced stage of HIV, increases maternal HIV/AIDS-related morbidity and mortality, enables the vertical transmission of HIV to newborns, facilitates the development of drug resistance, and missed opportunities for family planning (<xref ref-type="bibr" rid="B40">40</xref>). Nationally, there is a target for fulfilling the 90-90-90 strategy as a percentage of currently receiving antiretroviral therapy among all adults and children living with HIV to be 90&#x0025;, which is to decrease LTFU to less than 10&#x0025; (<xref ref-type="bibr" rid="B5">5</xref>). Therefore, this retrospective record review was conducted to determine the incidence and predictors of LTFU among pregnant and lactating women in the Option B&#x002B; PMTCT program in Northwest Ethiopia.</p>
<p>The overall incidence density of LTFU in the current study was 9.4 per 1,000 person-months by the end of the PMTCT follow-up period This finding is in agreement with a previous study conducted in Nekemte Hospital, Western Ethiopia (9 per 1,000 person-months observations) (<xref ref-type="bibr" rid="B28">28</xref>). This is due to the similarity in study times at which nationally different strategies were adopted to increase ART coverage and adherence. Among these, ART drug refill and clinical follow-up, including laboratory investigations, were performed in advance at the ART/PMTCT clinic. In addition, case managers who are trained lay workers, most of whom are people living with human immune deficiency virus, provide adherence and psychosocial services at these ART health facilities to decrease interruption from services (<xref ref-type="bibr" rid="B44">44</xref>, <xref ref-type="bibr" rid="B45">45</xref>). However, this finding is lower than that reported in study from Northeast Ethiopia (14.8 per 1,000 person-months observations) (<xref ref-type="bibr" rid="B27">27</xref>). This difference might be due to the difference in the study time that the study was initiated. The current study includes recent year data at which most strategies at a country level were implemented to decrease LTFU, such as bringing services closer to communities by expanding ART sites to above 1,500 health facilities and increasing service provision by expanding trained health personnel to decrease waiting times at the facility compared to previous studies. The variation could also be explained by the difference in the study settings, since this study was conducted at 1 referral hospital whereas a previous study was conducted in 4 hospitals and 10 health centers. Studies have shown that the magnitude of loss to follow-up varies according to the level of health institution (<xref ref-type="bibr" rid="B23">23</xref>, <xref ref-type="bibr" rid="B27">27</xref>). Moreover, the lower incidence of LTFU in the current study might be because different programs and measures have been implemented in the country in recent years to decrease the rate of LTFU women with HIV infection. Loss to follow up will be decreased by increasing trained human power, including midwives, frequent follow-up schedules, and better drug preparation (fixed-dose ART treatment) by providing better consideration for mothers to implement the program effectively (<xref ref-type="bibr" rid="B40">40</xref>). It is also lower than those of studies conducted in different African countries such as Uganda (<xref ref-type="bibr" rid="B15">15</xref>, <xref ref-type="bibr" rid="B16">16</xref>, <xref ref-type="bibr" rid="B18">18</xref>), South Africa (<xref ref-type="bibr" rid="B24">24</xref>), Malawi (<xref ref-type="bibr" rid="B14">14</xref>, <xref ref-type="bibr" rid="B46">46</xref>), and Kenya (<xref ref-type="bibr" rid="B19">19</xref>). This discrepancy might be due to the differences in study time, operational definition of the outcome variable, and characteristics of the study participants. For example, the study period in Malawi was a 3-year record review (<xref ref-type="bibr" rid="B14">14</xref>), whereas the current study incorporated recent years&#x2019; data that had improved ART coverage. Another explanation for the discrepancy in incidence rate was the characteristics of study participants; the study in Uganda incorporated 92&#x0025; of the population with a rural place of residence (<xref ref-type="bibr" rid="B16">16</xref>) compared to only 38.5&#x0025; in the current study. The operational definitions of studies in Kenya and South Africa (<xref ref-type="bibr" rid="B26">26</xref>, <xref ref-type="bibr" rid="B32">32</xref>) were missing 6&#x2005;months until the last follow-up visit compared to 3&#x2005;months in the current study. Furthermore, the rate of LTFU in the current study was lower than that in a study conducted in Myanmar, which was 7 per 1,000 person-years (<xref ref-type="bibr" rid="B11">11</xref>). This difference might be because the study in Myanmar included only pregnant women. Pregnancy-related symptoms and signs during antenatal care clinics (<xref ref-type="bibr" rid="B17">17</xref>) have a chance of dropping out from the PMTCT clinic (<xref ref-type="bibr" rid="B47">47</xref>).</p>
<p>The current study showed that the risk of LTFU among women residing in rural areas was higher than that among women residing in urban areas. Supporting findings have been reported in previous studies in Ethiopia and Brazil (<xref ref-type="bibr" rid="B10">10</xref>, <xref ref-type="bibr" rid="B28">28</xref>, <xref ref-type="bibr" rid="B48">48</xref>). Possible explanations for this might be that mothers from remote areas are forced to travel long distances to get to the nearest hospital, which necessarily involves high costs that lead to LTFU (<xref ref-type="bibr" rid="B16">16</xref>), and cannot easily get transport services due to poor/lack of road construction, making women walk long distances barefoot, which leads them to be less likely to adhere to Option B&#x002B; strategy (<xref ref-type="bibr" rid="B29">29</xref>), resulting in missing appointments (<xref ref-type="bibr" rid="B15">15</xref>, <xref ref-type="bibr" rid="B31">31</xref>). This justification is also supported by the report that lack of access to healthcare services leads to poor adherence and LTFU to Option B&#x002B; PMTCT drugs (<xref ref-type="bibr" rid="B15">15</xref>). Although this was not assessed in the current study, an additional explanation for the high risk of LTFU is that, in a rural setting, transport is costly because most mothers are farmers and housewives with low socioeconomic status (<xref ref-type="bibr" rid="B16">16</xref>).</p>
<p>This study also found that women who had no baseline viral load measurements were more likely to have LTFU than those who had baseline viral load measurement within 3&#x2005;months of PMTCT enrollment. This finding is supported by a study in Nigeria among the general population, missing viral load measurements increasing LTFU (<xref ref-type="bibr" rid="B49">49</xref>). This might be because when viral load measurements were taken during PMTCT enrolment, the healthcare provider classified women as high risk with a viral load of more than 1,000&#x2005;copies/mm<sup>3</sup> and low risk with a viral load of less than 1,000&#x2005;copies/mm<sup>3</sup>. Therefore, those in high-risk categories will be followed carefully and frequently in order not to miss the appointment time since it is a gold criterion to know the women in a good way or adhere to service provisions (<xref ref-type="bibr" rid="B40">40</xref>). Another possible explanation for the high rate of LTFU in those who had no baseline viral load measurement is that viral load measurement was implemented in advance after 2016 in Ethiopia. Another possible explanation could be that taking viral load measurement at baseline raises women&#x0027;s HIV-related literacy and awareness and might engage women in care (<xref ref-type="bibr" rid="B45">45</xref>).</p>
<p>Moreover, women with fair/poor drug adherence were more likely to have LTFU than women with good adherence. This finding is supported by studies conducted in Ethiopia (<xref ref-type="bibr" rid="B48">48</xref>) and Malawi (<xref ref-type="bibr" rid="B22">22</xref>). This might be because poor adherence to drugs is due to the feared side effects resulting in stopping taking ART treatments and lack of knowledge toward the importance of adherence to all appointments lead to stopping/missing the schedule of ART treatment (<xref ref-type="bibr" rid="B18">18</xref>).</p>
<p>The current study revealed that the risk of LTFU in women who started ART on the same day following HIV diagnosis was higher than that in women who started ART later following HIV diagnosis. This finding agrees with those of studies conducted in Northeast Ethiopia (<xref ref-type="bibr" rid="B27">27</xref>) and Malawi (<xref ref-type="bibr" rid="B20">20</xref>). This might be due to the need for sufficient time and information for clients to adjust and prepare themselves for lifetime treatment, psychologically, socially, and physically. Moreover, the reason for loss to follow-up for those women who started the same-day initiation might be due to the combined effect of ART side effects at the time of initiation and pregnancy-induced physiological side effects, such as regurgitation, nausea, and vomiting, which leads to loss in treatment follow-up. However, a study in southern Ethiopia suggested that pregnant women who started ART at the time of HIV diagnosis were more likely to adhere to Option B&#x002B; ART, resulting in increased retention in HIV care (<xref ref-type="bibr" rid="B29">29</xref>), which is contrary to the findings of this study. The current study is also against the study in South Africa, which showed that same-day antiretroviral therapy initiation in pregnancy is not associated with engagement in care (<xref ref-type="bibr" rid="B35">35</xref>). This might be due to the difference in study participants, in which the study in South Africa included only pregnant women.</p>
<p>The risk of LTFU among women who were receiving ART before PMTCT enrolment was lower than that among women who were enrolled in PMTCT. This finding is in agreement with studies conducted in different countries in Africa (<xref ref-type="bibr" rid="B19">19</xref>, <xref ref-type="bibr" rid="B23">23</xref>, <xref ref-type="bibr" rid="B28">28</xref>). A possible explanation for this might be that a known HIV woman on ART before enrolment had experienced ART treatment and might have good awareness about ART treatment, drug side effects, and drug adherence than a newly enrolled woman. Evidence also showed that a new HIV diagnosis during routine antenatal screening can be attended by different degrees of shock and denial and may lead to difficulty accepting immediate initiation of lifelong treatment, resulting in a loss to follow-up (<xref ref-type="bibr" rid="B46">46</xref>). This study also supported a previous study done in South Africa, which stated that being newly diagnosed with HIV was a positively significant predictor of disengagement from ART treatment (<xref ref-type="bibr" rid="B24">24</xref>).</p>
<p>The findings of the current study also revealed that women who had ART side effects during PMTCT follow-up had a higher risk of LTFU than those who had no ART side effects. The findings of this study are supported by studies in Uganda (<xref ref-type="bibr" rid="B16">16</xref>) and Malawi (<xref ref-type="bibr" rid="B9">9</xref>, <xref ref-type="bibr" rid="B26">26</xref>, <xref ref-type="bibr" rid="B36">36</xref>). This might be due to less counseling on the side effects of ART and less support for women experiencing challenges with tolerability, including options to switch regimens (<xref ref-type="bibr" rid="B24">24</xref>).</p>
<p>All in all, the incidence rate of LTFU was higher in the last month of the PMTCT follow-up period, implying a lack of proper linkage and referral systems between PMTCT services and ART clinics. In addition, contrary to the current study, variables such as educational status, maternal age, and baseline CD4 cell count showed statistically significant associations with LTFU among HIV-infected women receiving PMTCT services in previous studies conducted in different African countries (<xref ref-type="bibr" rid="B15">15</xref>, <xref ref-type="bibr" rid="B23">23</xref>, <xref ref-type="bibr" rid="B24">24</xref>, <xref ref-type="bibr" rid="B26">26</xref>, <xref ref-type="bibr" rid="B27">27</xref>, <xref ref-type="bibr" rid="B36">36</xref>). However, these variables were not statistically significant in this study. This difference might be because the predictors of LTFU varied from one geographical area to another due to the differences in the economic status of the study participants and infrastructure in the health facilities.</p>
<sec id="s4a"><title>Limitations of the study</title>
<p>This study has some limitations that must be considered before interpreting the results. First, as we conducted a thorough review of records, we did not include important predictors of LTFU such as stigma, distance to hospital, and social support. Second, the true incidence of LTFU might have been underestimated and/or overestimated because of incomplete documentation of data and classification errors. Finally, there are limitations related to the abstraction of routinely collected data.</p>
</sec>
</sec>
<sec id="s5" sec-type="conclusions"><title>Conclusion</title>
<p>The current study revealed that the incidence of LTFU dramatically and consistently decreased as Option B&#x002B; matured from 38&#x0025; in 2013 to 6&#x0025; in 2019. A high rate of LTFU was observed in the last month of PMTCT follow-up. The study also found a lower rate of LTFU among HIV-positive women than in previous studies, but it was slightly higher than the WHO target. The place of residence, recent adherence level, baseline viral load measurement, known HIV status, time of ART initiation, drug side effects, and religion were found to be predictors of LTFU. We recommend that the hospital pay more attention to rural dwellers to decrease LTFU in collaboration with the Zonal Health Department, the Woreda Health Office, and stakeholders. Information about optimal ART drug adherence and viral load measurement is recommended because these are the main contributing factors to the decline in LTFU over time. Better consideration should be given to ART side effects that are in adherence and retention. We have recommended research on primary data that incorporates maternal conditions, community, behavioral, and cultural factors such as women&#x0027;s attitudes toward maternal ART treatment using qualitative studies. Moreover, it is better to be done as a prospective and prognostic model for the risk prediction of LTFU. The results of this study will help achieve the goal of the Joint United Nations Program on HIV/AIDS, which is to reduce mother-to-child transmission of HIV by 5&#x0025;.</p>
</sec>
</body>
<back>
<sec id="s6" sec-type="data-availability"><title>Data availability statement</title>
<p>The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.</p>
</sec>
<sec id="s7" sec-type="ethics-statement"><title>Ethics statement</title>
<p>Ethical clearance was obtained from the Ethical Committee of the Institute of Public Health at University of Gondar. First a formal letter was written from the University of Gondar to Gondar Comprehensive and Specialized Hospital. Moreover, permission for data collection was granted from the hospital. Written informed consent for participation was not required for this study in accordance with the national legislation and the institutional requirements.</p>
</sec>
<sec id="s8" sec-type="author-contributions"><title>Author contributions</title>
<p>MA, AB, and MY developed the proposal and participated in data collection supervision, entry, and analysis. All authors contributed to the article and approved the submitted version.</p>
</sec>
<sec id="s9" sec-type="funding-information"><title>Funding</title>
<p>The University of Gondar and Grant number: IPH/837/6/2012 covered the costs of data collectors and supervisors per diem. The funding organization had no role in designing the study, data collection, or manuscript preparation.</p>
</sec>
<ack><title>Acknowledgments</title>
<p>We thank the University of Gondar for covering the data collectors and supervisors per diem. We would also like to thank the data collectors and supervisors.</p>
</ack>
<sec id="s10" sec-type="COI-statement"><title>Conflict of interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec id="s11" sec-type="disclaimer"><title>Publisher&#x0027;s note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
<ref-list><title>References</title>
<ref id="B1"><label>1.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Vrazo</surname><given-names>AC</given-names></name><name><surname>Sullivan</surname><given-names>D</given-names></name><name><surname>Ryan Phelps</surname><given-names>B</given-names></name></person-group>. <article-title>Eliminating mother-to-child transmission of HIV by 2030: 5 strategies to ensure continued progress</article-title>. <source>J Glob Health Sci Pract</source>. (<year>2018</year>) <volume>6</volume>(<issue>2</issue>):<fpage>249</fpage>&#x2013;<lpage>56</lpage>. <pub-id pub-id-type="doi">10.9745/GHSP-D-17-00097</pub-id></citation></ref>
<ref id="B2"><label>2.</label><citation citation-type="book"><collab>World Health Organization (WHO)</collab>. <source>Consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infection: Recommendations for a public health approach</source>. <edition>2nd ed</edition>. <publisher-loc>Geneva: World Health Organization</publisher-loc> (<year>2016</year>).</citation></ref>
<ref id="B3"><label>3.</label><citation citation-type="other">Joint United Nations Programme on HIV/AIDS. <italic>Start free stay free AIDS free</italic>. Progress report. Geneva, Switzerland (2019). Available at: <ext-link ext-link-type="uri" xlink:href="https://www.unaids.org/en/resources/documents/2019/20190722_UNAIDS_SFSFAF_2019">https://www.unaids.org/en/resources/documents/2019/20190722_UNAIDS_SFSFAF_2019</ext-link></citation></ref>
<ref id="B4"><label>4.</label><citation citation-type="other"><comment><italic>United Nations Programme on HIV/AIDS (UNAIDS): Global HIV &#x0026; AIDS statistics &#x2014; fact sheet</italic>. Geneva, Switzerland (2018). Available at:</comment> <ext-link ext-link-type="uri" xlink:href="https://www.unaids.org/en/resources/fact-sheet">https://www.unaids.org/en/resources/fact-sheet</ext-link></citation></ref>
<ref id="B5"><label>5.</label><citation citation-type="book"><collab>World Health Organization (WHO)</collab>. <source>Programmatic update use of antiretroviral drugs for treating pregnant women and preventing HIV infection in infants</source>. <publisher-loc>Geneva</publisher-loc>: <publisher-name>HIV/AIDs Program</publisher-name> (<year>2012</year>).</citation></ref>
<ref id="B6"><label>6.</label><citation citation-type="book"><source>Options B and B&#x002B;: key considerations for countries to implement an equity-focused approach</source>. <publisher-loc>Geneva</publisher-loc>: <publisher-name>UNICEF</publisher-name> (<year>2012</year>).</citation></ref>
<ref id="B7"><label>7.</label><citation citation-type="other"><collab>Update WP</collab>. <comment>Use of antiretroviral drugs for treating pregnant women and preventing HIV infection in infants. Geneva: WHO (2012)</comment>.</citation></ref>
<ref id="B8"><label>8.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>You</surname><given-names>D</given-names></name><name><surname>Hug</surname><given-names>L</given-names></name><name><surname>Ejdemyr</surname><given-names>S</given-names></name><name><surname>Idele</surname><given-names>P</given-names></name><name><surname>Hogan</surname><given-names>D</given-names></name><name><surname>Mathers</surname><given-names>C</given-names></name><etal/></person-group> <article-title>Global, regional, and national levels and trends in under-5 mortality between 1990 and 2015, with scenario-based projections to 2030: a systematic analysis by the UN inter-agency group for child mortality estimation</article-title>. <source>J Lancet.</source> (<year>2015</year>) <volume>386</volume>(<issue>10010</issue>):<fpage>2275</fpage>&#x2013;<lpage>86</lpage>. <pub-id pub-id-type="doi">10.1016/S0140-6736(15)00120-8</pub-id></citation></ref>
<ref id="B9"><label>9.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Atanga</surname><given-names>PN</given-names></name><name><surname>Ndetan</surname><given-names>HT</given-names></name><name><surname>Achidi</surname><given-names>EA</given-names></name><name><surname>Meriki</surname><given-names>HD</given-names></name><name><surname>Hoelscher</surname><given-names>M</given-names></name><name><surname>Kroidl</surname><given-names>A</given-names></name></person-group>. <article-title>Retention in care and reasons for discontinuation of lifelong antiretroviral therapy in a cohort of Cameroonian pregnant and breastfeeding HIV-positive women initiating &#x201C;Option B&#x002B;&#x201D; in the south west region</article-title>. <source>J Trop Med Int Health</source>. (<year>2017</year>) <volume>22</volume>(<issue>2</issue>):<fpage>161</fpage>&#x2013;<lpage>70</lpage>. <pub-id pub-id-type="doi">10.1111/tmi.12816</pub-id></citation></ref>
<ref id="B10"><label>10.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kim</surname><given-names>MH</given-names></name><name><surname>Zhou</surname><given-names>A</given-names></name><name><surname>Mazenga</surname><given-names>A</given-names></name><name><surname>Ahmed</surname><given-names>S</given-names></name><name><surname>Markham</surname><given-names>C</given-names></name><name><surname>Zomba</surname><given-names>G</given-names></name><etal/></person-group> <article-title>Why did I stop? Barriers and facilitators to uptake and adherence to ART in Option B&#x002B; HIV care in Lilongwe, Malawi</article-title>. <source>PLoS One</source>. (<year>2016</year>) <volume>11</volume>(<issue>2</issue>):<fpage>e0149527</fpage>. <pub-id pub-id-type="doi">10.1371/journal.pone.0149527</pub-id><pub-id pub-id-type="pmid">26901563</pub-id></citation></ref>
<ref id="B11"><label>11.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Gouveia</surname><given-names>DC</given-names></name><name><surname>da Silva</surname><given-names>PA</given-names></name><name><surname>Pontes</surname><given-names>GA</given-names></name></person-group>. <article-title>Predictors of loss to follow-up among children registered in an HIV prevention mother-to-child transmission cohort study in Pernambuco, Brazil</article-title>. <source>J BMC Public Health</source>. (<year>2014</year>) <volume>14</volume>(<issue>1</issue>):<fpage>1232</fpage>. <pub-id pub-id-type="doi">10.1186/1471-2458-14-1232</pub-id></citation></ref>
<ref id="B12"><label>12.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kyaw</surname><given-names>KWY</given-names></name><name><surname>Oo</surname><given-names>MM</given-names></name><name><surname>Kyaw</surname><given-names>NTT</given-names></name><name><surname>Phyo</surname><given-names>KH</given-names></name><name><surname>Aung</surname><given-names>TK</given-names></name><name><surname>Mya</surname><given-names>T</given-names></name><etal/></person-group> <article-title>Low mother-to-child HIV transmission rate but high loss-to-follow-up among mothers and babies in Mandalay, Myanmar; a cohort study</article-title>. <source>PLoS One</source>. (<year>2017</year>) <volume>12</volume>(<issue>9</issue>):<fpage>e0184426</fpage>. <pub-id pub-id-type="doi">10.1371/journal.pone.0184426</pub-id><pub-id pub-id-type="pmid">28886165</pub-id></citation></ref>
<ref id="B13"><label>13.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Dzangare</surname><given-names>J</given-names></name><name><surname>Takarinda</surname><given-names>KC</given-names></name><name><surname>Harries</surname><given-names>AD</given-names></name><name><surname>Tayler-Smith</surname><given-names>K</given-names></name><name><surname>Mhangara</surname><given-names>M</given-names></name><name><surname>Apollo</surname><given-names>TM</given-names></name><etal/></person-group> <article-title>HIV testing uptake and retention in care of HIV-infected pregnant and breastfeeding women initiated on &#x201C;Option B&#x002B;&#x201D; in rural Zimbabwe</article-title>. <source>J Trop Med Int Health</source>. (<year>2016</year>) <volume>21</volume>(<issue>2</issue>):<fpage>202</fpage>&#x2013;<lpage>9</lpage>. <pub-id pub-id-type="doi">10.1111/tmi.12637</pub-id></citation></ref>
<ref id="B14"><label>14.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Haas</surname><given-names>AD</given-names></name><name><surname>Tenthani</surname><given-names>L</given-names></name><name><surname>Msukwa</surname><given-names>MT</given-names></name><name><surname>Tal</surname><given-names>K</given-names></name><name><surname>Jahn</surname><given-names>A</given-names></name><name><surname>Gadabu</surname><given-names>OJ</given-names></name><etal/></person-group> <article-title>Retention in care during the first 3 years of antiretroviral therapy for women in Malawi&#x2019;s Option B&#x002B; program: an observational cohort study</article-title>. <source>J Lancet HIV</source>. (<year>2016</year>) <volume>3</volume>(<issue>4</issue>):<fpage>e175</fpage>&#x2013;<lpage>e82</lpage>. <pub-id pub-id-type="doi">10.1016/S2352-3018(16)00008-4</pub-id></citation></ref>
<ref id="B15"><label>15.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kiwanuka</surname><given-names>G</given-names></name><name><surname>Kiwanuka</surname><given-names>N</given-names></name><name><surname>Muneza</surname><given-names>F</given-names></name><name><surname>Nabirye</surname><given-names>J</given-names></name><name><surname>Oporia</surname><given-names>F</given-names></name><name><surname>Odikro</surname><given-names>MA</given-names></name><etal/></person-group> <article-title>Retention of HIV-infected pregnant and breastfeeding women on Option B&#x002B; in Gomba District, Uganda: a retrospective cohort study</article-title>. <source>J BMC Infect Dis</source>. (<year>2018</year>) <volume>18</volume>(<issue>1</issue>):<fpage>533</fpage>. <pub-id pub-id-type="doi">10.1186/s12879-018-3450-9</pub-id></citation></ref>
<ref id="B16"><label>16.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kweyamba</surname><given-names>M</given-names></name><name><surname>Buregyeya</surname><given-names>E</given-names></name><name><surname>Kusiima</surname><given-names>J</given-names></name><name><surname>Kweyamba</surname><given-names>V</given-names></name><name><surname>Mukose</surname><given-names>AD</given-names></name></person-group>. <article-title>Loss to follow-up among HIV positive pregnant and lactating mothers on lifelong antiretroviral therapy for PMTCT in rural Uganda</article-title>. <source>J Adv Public Health</source>. (<year>2018</year>). <pub-id pub-id-type="doi">10.1155/2018/7540587</pub-id></citation></ref>
<ref id="B17"><label>17.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Llenas-Garc&#x00ED;a</surname><given-names>J</given-names></name><name><surname>Wikman-Jorgensen</surname><given-names>P</given-names></name><name><surname>Hobbins</surname><given-names>M</given-names></name><name><surname>Mussa</surname><given-names>MA</given-names></name><name><surname>Ehmer</surname><given-names>J</given-names></name><name><surname>Keiser</surname><given-names>O</given-names></name><etal/></person-group> <article-title>Retention in care of HIV-infected pregnant and lactating women starting ART under Option B&#x002B; in rural Mozambique</article-title>. <source>J Trop Med Int Health</source>. (<year>2016</year>) <volume>21</volume>(<issue>8</issue>):<fpage>1003</fpage>&#x2013;<lpage>12</lpage>. <pub-id pub-id-type="doi">10.1111/tmi.12728</pub-id></citation></ref>
<ref id="B18"><label>18.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Obai</surname><given-names>G</given-names></name><name><surname>Mubeezi</surname><given-names>R</given-names></name><name><surname>Makumbi</surname><given-names>F</given-names></name></person-group>. <article-title>Rate and associated factors of non-retention of mother-baby pairs in HIV care in the elimination of mother-to-child transmission program, Gulu-Uganda: a cohort study</article-title>. <source>J BMC Health Ser Res</source>. (<year>2017</year>) <volume>17</volume>(<issue>1</issue>):<fpage>48</fpage>. <pub-id pub-id-type="doi">10.1186/s12913-017-1998-5</pub-id></citation></ref>
<ref id="B19"><label>19.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Woelk</surname><given-names>GB</given-names></name><name><surname>Ndatimana</surname><given-names>D</given-names></name><name><surname>Behan</surname><given-names>S</given-names></name><name><surname>Mukaminega</surname><given-names>M</given-names></name><name><surname>Nyirabahizi</surname><given-names>E</given-names></name><name><surname>Hoffman</surname><given-names>HJ</given-names></name><etal/></person-group> <article-title>Retention of mothers and infants in the prevention of mother-to-child transmission of HIV programs is associated with individual and facility-level factors in Rwanda</article-title>. <source>J Int AIDS Soc</source>. (<year>2016</year>) <volume>19</volume>:<fpage>20837</fpage>. <pub-id pub-id-type="doi">10.7448/IAS.19.5.20837</pub-id><pub-id pub-id-type="pmid">27443268</pub-id></citation></ref>
<ref id="B20"><label>20.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Chan</surname><given-names>AK</given-names></name><name><surname>Kanike</surname><given-names>E</given-names></name><name><surname>Bedell</surname><given-names>R</given-names></name><name><surname>Mayuni</surname><given-names>I</given-names></name><name><surname>Manyera</surname><given-names>R</given-names></name><name><surname>Mlotha</surname><given-names>W</given-names></name><etal/></person-group> <article-title>Same-day HIV diagnosis and antiretroviral therapy initiation affect retention in Option B&#x002B; prevention of mother-to-child transmission services at antenatal care in Zomba District, Malawi</article-title>. <source>J Int AIDS Soc</source>. (<year>2016</year>) <volume>19</volume>(<issue>1</issue>):<fpage>20672</fpage>. <pub-id pub-id-type="doi">10.7448/IAS.19.1.20672</pub-id><pub-id pub-id-type="pmid">26976377</pub-id></citation></ref>
<ref id="B21"><label>21.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Ford</surname><given-names>D</given-names></name><name><surname>Muzambi</surname><given-names>M</given-names></name><name><surname>Nkhata</surname><given-names>MJ</given-names></name><name><surname>Abongomera</surname><given-names>G</given-names></name><name><surname>Joseph</surname><given-names>S</given-names></name><name><surname>Ndlovu</surname><given-names>M</given-names></name><etal/></person-group> <article-title>Implementation of antiretroviral therapy for life in pregnant/breastfeeding HIV&#x002B; women (Option B&#x002B;) alongside rollout and changing guidelines for ART initiation in rural Zimbabwe: the lablite project experience</article-title>. <source>J Acquir Immune Defic Syndr</source>. (<year>2017</year>) <volume>74</volume>(<issue>5</issue>):<fpage>508</fpage>. <pub-id pub-id-type="doi">10.1097/QAI.0000000000001267</pub-id><pub-id pub-id-type="pmid">27984555</pub-id></citation></ref>
<ref id="B22"><label>22.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Haas</surname><given-names>AD</given-names></name><name><surname>Msukwa</surname><given-names>MT</given-names></name><name><surname>Egger</surname><given-names>M</given-names></name><name><surname>Tenthani</surname><given-names>L</given-names></name><name><surname>Tweya</surname><given-names>H</given-names></name><name><surname>Jahn</surname><given-names>A</given-names></name><etal/></person-group> <article-title>Adherence to antiretroviral therapy during and after pregnancy: cohort study on women receiving care in Malawi&#x2019;s Option B&#x002B; program</article-title>. <source>J Clin Infect Dis</source>. (<year>2016</year>) <volume>63</volume>(<issue>9</issue>):<fpage>1227</fpage>&#x2013;<lpage>35</lpage>. <pub-id pub-id-type="doi">10.1093/cid/ciw500</pub-id></citation></ref>
<ref id="B23"><label>23.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Landes</surname><given-names>M</given-names></name><name><surname>Sodhi</surname><given-names>S</given-names></name><name><surname>Matengeni</surname><given-names>A</given-names></name><name><surname>Meaney</surname><given-names>C</given-names></name><name><surname>van Lettow</surname><given-names>M</given-names></name><name><surname>Chan</surname><given-names>A</given-names></name><etal/></person-group> <article-title>Characteristics and outcomes of women initiating ART during pregnancy versus breastfeeding in Option B&#x002B; in Malawi</article-title>. <source>J BMC Public Health</source>. (<year>2016</year>) <volume>16</volume>(<issue>1</issue>):<fpage>713</fpage>. <pub-id pub-id-type="doi">10.1186/s12889-016-3380-7</pub-id></citation></ref>
<ref id="B24"><label>24.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Phillips</surname><given-names>T</given-names></name><name><surname>Thebus</surname><given-names>E</given-names></name><name><surname>Bekker</surname><given-names>LG</given-names></name><name><surname>Mcintyre</surname><given-names>J</given-names></name><name><surname>Abrams</surname><given-names>EJ</given-names></name><name><surname>Myer</surname><given-names>L</given-names></name></person-group>. <article-title>Disengagement of HIV-positive pregnant and postpartum women from antiretroviral therapy services: a cohort study</article-title>. <source>J Int AIDS Soc</source>. (<year>2014</year>) <volume>17</volume>(<issue>1</issue>):<fpage>19242</fpage>. <pub-id pub-id-type="doi">10.7448/IAS.17.1.19242</pub-id><pub-id pub-id-type="pmid">25301494</pub-id></citation></ref>
<ref id="B25"><label>25.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Tenthani</surname><given-names>L</given-names></name><name><surname>Haas</surname><given-names>AD</given-names></name><name><surname>Tweya</surname><given-names>H</given-names></name><name><surname>Jahn</surname><given-names>A</given-names></name><name><surname>van Oosterhout</surname><given-names>JJ</given-names></name><name><surname>Chimbwandira</surname><given-names>F</given-names></name><etal/></person-group> <article-title>Retention in care under universal antiretroviral therapy for HIV-infected pregnant and breastfeeding women (&#x201C;Option B&#x002B;&#x201D;) in Malawi</article-title>. <source>J AIDS</source>. (<year>2014</year>) <volume>28</volume>(<issue>4</issue>):<fpage>589</fpage>. <pub-id pub-id-type="doi">10.1097/QAD.0000000000000143</pub-id></citation></ref>
<ref id="B26"><label>26.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Tweya</surname><given-names>H</given-names></name><name><surname>Gugsa</surname><given-names>S</given-names></name><name><surname>Hosseinipour</surname><given-names>M</given-names></name><name><surname>Speight</surname><given-names>C</given-names></name><name><surname>Ng&#x0027;ambi</surname><given-names>W</given-names></name><name><surname>Bokosi</surname><given-names>M</given-names></name><etal/></person-group> <article-title>Understanding factors, outcomes, and reasons for loss to follow-up among women in Option B&#x002B; PMTCT program in Lilongwe, Malawi</article-title>. <source>J Trop Med Int Health</source>. (<year>2014</year>) <volume>19</volume>(<issue>11</issue>):<fpage>1360</fpage>&#x2013;<lpage>6</lpage>. <pub-id pub-id-type="doi">10.1111/tmi.12369</pub-id></citation></ref>
<ref id="B27"><label>27.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Mitiku</surname><given-names>I</given-names></name><name><surname>Arefayne</surname><given-names>M</given-names></name><name><surname>Mesfin</surname><given-names>Y</given-names></name><name><surname>Gizaw</surname><given-names>M</given-names></name></person-group>. <article-title>Factors associated with loss to follow-up among women in Option B&#x002B; PMTCT program in northeast Ethiopia: a retrospective cohort study</article-title>. <source>J Int AIDS Soc</source>. (<year>2016</year>) <volume>19</volume>(<issue>1</issue>):<fpage>20662</fpage>. <pub-id pub-id-type="doi">10.7448/IAS.19.1.20662</pub-id><pub-id pub-id-type="pmid">27005750</pub-id></citation></ref>
<ref id="B28"><label>28.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Tolossa</surname><given-names>T</given-names></name><name><surname>Kassa</surname><given-names>GM</given-names></name><name><surname>Chanie</surname><given-names>H</given-names></name><name><surname>Abajobir</surname><given-names>A</given-names></name><name><surname>Mulisa</surname><given-names>D</given-names></name></person-group>. <article-title>Incidence and predictors of lost to follow-up among women under Option B&#x002B; PMTCT program in western Ethiopia: a retrospective follow-up study</article-title>. <source>J BMC Res Notes</source>. (<year>2020</year>) <volume>13</volume>(<issue>1</issue>):<fpage>18</fpage>. <pub-id pub-id-type="doi">10.1186/s13104-019-4882-z</pub-id></citation></ref>
<ref id="B29"><label>29.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Tesfaye</surname><given-names>DJ</given-names></name><name><surname>Hibistu</surname><given-names>DT</given-names></name><name><surname>Abebo</surname><given-names>TA</given-names></name><name><surname>Asfaw</surname><given-names>FT</given-names></name><name><surname>Lukas</surname><given-names>K</given-names></name><name><surname>Laelago</surname><given-names>T</given-names></name><etal/></person-group> <article-title>Option B plus antiretroviral therapy adherence and associated factors among HIV-positive pregnant women in southern Ethiopia</article-title>. <source>J BMC Pregnancy</source>. (<year>2019</year>) <volume>19</volume>(<issue>1</issue>):<fpage>82</fpage>. <pub-id pub-id-type="doi">10.1186/s12884-019-2228-4</pub-id></citation></ref>
<ref id="B30"><label>30.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Musomba</surname><given-names>R</given-names></name><name><surname>Mubiru</surname><given-names>F</given-names></name><name><surname>Nakalema</surname><given-names>S</given-names></name><name><surname>Mackline</surname><given-names>H</given-names></name><name><surname>Kalule</surname><given-names>I</given-names></name><name><surname>Kiragga</surname><given-names>AN</given-names></name><etal/></person-group> <article-title>Describing point of entry into care and being lost to program in a cohort of HIV-positive pregnant women in a large urban center in Uganda</article-title>. <source>J AIDS Res</source>. (<year>2017</year>) <volume>9</volume>(<issue>1</issue>):3527563. <pub-id pub-id-type="doi">10.1155/2017/3527563</pub-id>.</citation></ref>
<ref id="B31"><label>31.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Mukosha</surname><given-names>M</given-names></name><name><surname>Chiyesu</surname><given-names>G</given-names></name><name><surname>Vwalika</surname><given-names>B</given-names></name></person-group>. <article-title>Adherence to antiretroviral therapy among HIV infected pregnant women in public health sectors: a pilot of Chilenje level one Hospital Lusaka, Zambia</article-title>. <source>Pan Afr Med J</source>. (<year>2020</year>) <volume>35</volume>(<issue>49</issue>):49. <pub-id pub-id-type="doi">10.11604/pamj.2020.35.49.20078</pub-id><pub-id pub-id-type="pmid">32537054</pub-id></citation></ref>
<ref id="B32"><label>32.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Schnack</surname><given-names>A</given-names></name><name><surname>Rempis</surname><given-names>E</given-names></name><name><surname>Decker</surname><given-names>S</given-names></name><name><surname>Braun</surname><given-names>V</given-names></name><name><surname>Rubaihayo</surname><given-names>J</given-names></name><name><surname>Busingye</surname><given-names>P</given-names></name><etal/></person-group> <article-title>Prevention of mother-to-child transmission of HIV in Option B&#x002B; era: uptake and adherence during pregnancy in western Uganda</article-title>. <source>J AIDS Patient Care</source>. (<year>2016</year>) <volume>30</volume>(<issue>3</issue>):<fpage>110</fpage>&#x2013;<lpage>8</lpage>. <pub-id pub-id-type="doi">10.1089/apc.2015.0318</pub-id></citation></ref>
<ref id="B33"><label>33.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Hoffman</surname><given-names>RM</given-names></name><name><surname>Phiri</surname><given-names>K</given-names></name><name><surname>Parent</surname><given-names>J</given-names></name><name><surname>Grotts</surname><given-names>J</given-names></name><name><surname>Elashoff</surname><given-names>D</given-names></name><name><surname>Kawale</surname><given-names>P</given-names></name><etal/></person-group> <article-title>Factors associated with retention in Option B+ in Malawi: a case control study</article-title>. <source>J Int AIDS Soc</source>. (<year>2017</year>) <volume>20</volume>(<issue>1</issue>):<fpage>21464</fpage>. <pub-id pub-id-type="doi">10.7448/IAS.20.01.21464</pub-id><pub-id pub-id-type="pmid">28453243</pub-id></citation></ref>
<ref id="B34"><label>34.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Joseph</surname><given-names>J</given-names></name><name><surname>Gotora</surname><given-names>T</given-names></name><name><surname>Erlwanger</surname><given-names>AS</given-names></name><name><surname>Mushavi</surname><given-names>A</given-names></name><name><surname>Zizhou</surname><given-names>S</given-names></name><name><surname>Masuka</surname><given-names>N</given-names></name><etal/></person-group> <article-title>Impact of point-of-care CD4 testing on retention in care among HIV-positive pregnant and breastfeeding women in the context of Option B&#x002B; in Zimbabwe: a cluster randomized controlled trial</article-title>. <source>J Acquir Immune Defic Syndr</source>. (<year>2017</year>) <volume>75</volume>:<fpage>S190</fpage>&#x2013;<lpage>7</lpage>. <pub-id pub-id-type="doi">10.1097/QAI.0000000000001341</pub-id><pub-id pub-id-type="pmid">28498189</pub-id></citation></ref>
<ref id="B35"><label>35.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Langwenya</surname><given-names>N</given-names></name><name><surname>Phillips</surname><given-names>TK</given-names></name><name><surname>Brittain</surname><given-names>K</given-names></name><name><surname>Zerbe</surname><given-names>A</given-names></name><name><surname>Abrams</surname><given-names>EJ</given-names></name><name><surname>Myer</surname><given-names>L</given-names></name></person-group>. <article-title>Same-day antiretroviral therapy (ART) initiation in pregnancy is not associated with viral suppression or engagement in care: a cohort study</article-title>. <source>J Int AIDS Soc</source>. (<year>2018</year>) <volume>21</volume>(<issue>6</issue>):<fpage>e25133</fpage>. <pub-id pub-id-type="doi">10.1002/jia2.25133</pub-id><pub-id pub-id-type="pmid">29939483</pub-id></citation></ref>
<ref id="B36"><label>36.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Hoffman</surname><given-names>RM</given-names></name><name><surname>Phiri</surname><given-names>K</given-names></name><name><surname>Parent</surname><given-names>J</given-names></name><name><surname>Grotts</surname><given-names>J</given-names></name><name><surname>Elashoff</surname><given-names>D</given-names></name><name><surname>Kawale</surname><given-names>P</given-names></name><etal/></person-group> <article-title>Factors associated with retention in Option B&#x002B; in Malawi: a case-control study</article-title>. <source>J Int AIDS Soc</source>. (<year>2017</year>) <volume>20</volume>(<issue>1</issue>):<fpage>21464</fpage>. <pub-id pub-id-type="doi">10.7448/IAS.20.01.21464</pub-id><pub-id pub-id-type="pmid">28453243</pub-id></citation></ref>
<ref id="B37"><label>37.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Onoya</surname><given-names>D</given-names></name><name><surname>Sineke</surname><given-names>T</given-names></name><name><surname>Brennan</surname><given-names>AT</given-names></name><name><surname>Long</surname><given-names>L</given-names></name><name><surname>Fox</surname><given-names>MP</given-names></name></person-group>. <article-title>Timing of pregnancy, postpartum risk of virologic failure and loss to follow-up among HIV-positive women</article-title>. <source>J AIDS</source>. (<year>2017</year>) <volume>31</volume>(<issue>11</issue>):<fpage>1593</fpage>. <pub-id pub-id-type="doi">10.1097/QAD.0000000000001517</pub-id></citation></ref>
<ref id="B38"><label>38.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Demissie</surname><given-names>DB</given-names></name><name><surname>Erena</surname><given-names>MM</given-names></name><name><surname>Haile</surname><given-names>MT</given-names></name></person-group>, editors. <article-title>Assessment of loss to follow-up (LTFU) and associated factors among pregnant women initiated antiretroviral under option B&#x002B; in selected health facilities of west zone oromia, Ethiopia</article-title>. <source>J EC Gynaecol</source>. (<year>2019</year>) <volume>8</volume>:<fpage>314</fpage>&#x2013;<lpage>21</lpage>.</citation></ref>
<ref id="B39"><label>39.</label><citation citation-type="other"><comment>Central Statistical Agency</comment>. <source>Federal democratic republic of Ethiopia central statistical agency population projection of Ethiopia for all regions at wereda level from 2014&#x2013;2017</source>. <comment>Available at:</comment> <ext-link ext-link-type="uri" xlink:href="http://www.statsethiopia.gov.et/wp-content/uploads/2019/05/Population-Projection-At-Wereda-Level-from-2014-2017.pdf">http://www.statsethiopia.gov.et/wp-content/uploads/2019/05/Population-Projection-At-Wereda-Level-from-2014-2017.pdf</ext-link></citation></ref>
<ref id="B40"><label>40.</label><citation citation-type="other"><comment>Ministry of Health (Ethiopia): national consolidated guidelines for comprehensive HIV prevention, care, and treatment</comment> (<year>2018</year>). <comment>Available at:</comment> <ext-link ext-link-type="uri" xlink:href="https://www.childrenandaids.org/sites/default/files/2017-05/Ethiopia-Consolidated-ART-Guideline-2014.pdf">https://www.childrenandaids.org/sites/default/files/2017-05/Ethiopia-Consolidated-ART-Guideline-2014.pdf</ext-link></citation></ref>
<ref id="B41"><label>41.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Chi</surname><given-names>BH</given-names></name><name><surname>Yiannoutsos</surname><given-names>CT</given-names></name><name><surname>Westfall</surname><given-names>AO</given-names></name><name><surname>Newman</surname><given-names>JE</given-names></name><name><surname>Zhou</surname><given-names>J</given-names></name><name><surname>Cesar</surname><given-names>C</given-names></name><etal/></person-group> <article-title>Universal definition of loss to follow-up in HIV treatment programs: a statistical analysis of 111 facilities in Africa, Asia, and Latin America</article-title>. <source>PLoS Med</source>. (<year>2011</year>) <volume>8</volume>(<issue>10</issue>):e1001111. <pub-id pub-id-type="doi">10.1371/journal.pmed.1001111</pub-id>.<pub-id pub-id-type="pmid">22039357</pub-id></citation></ref>
<ref id="B42"><label>42.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Cohen</surname><given-names>MS</given-names></name><name><surname>Chen</surname><given-names>YQ</given-names></name><name><surname>McCauley</surname><given-names>M</given-names></name><name><surname>Gamble</surname><given-names>T</given-names></name><name><surname>Hosseinipour</surname><given-names>MC</given-names></name><name><surname>Kumarasamy</surname><given-names>N</given-names></name><etal/></person-group> <article-title>Antiretroviral therapy for the prevention of HIV-1 transmission</article-title>. <source>N Engl J Med</source>. (<year>2016</year>) <volume>375</volume>(<issue>9</issue>):<fpage>830</fpage>&#x2013;<lpage>9</lpage>. <pub-id pub-id-type="doi">10.1056/NEJMoa1600693</pub-id><pub-id pub-id-type="pmid">27424812</pub-id></citation></ref>
<ref id="B43"><label>43.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Gupta</surname><given-names>I</given-names></name><name><surname>Trivedi</surname><given-names>M</given-names></name><name><surname>Kandamuthan</surname><given-names>S</given-names></name></person-group>. <article-title>An analysis of recurrent costs of the free ART program of the government of India</article-title>. <source>J Growth Equity Environ Popul</source>. (<year>2006</year>) <volume>392</volume>.</citation></ref>
<ref id="B44"><label>44.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Grimsrud</surname><given-names>A</given-names></name><name><surname>Barnabas</surname><given-names>RV</given-names></name><name><surname>Ehrenkranz</surname><given-names>P</given-names></name><name><surname>Ford</surname><given-names>N</given-names></name></person-group>. <article-title>Evidence for scale-up: the differentiated care research agenda</article-title>. <source>J Int AIDS Soc</source>. (<year>2017</year>) <volume>20</volume>:<fpage>22024</fpage>. <pub-id pub-id-type="doi">10.7448/IAS.20.5.22024</pub-id><pub-id pub-id-type="pmid">28770588</pub-id></citation></ref>
<ref id="B45"><label>45.</label><citation citation-type="book"><collab>Federal HIV/AIDS Prevention and Control Office</collab>. <source>HIV prevention in Ethiopia national road map 2018&#x2013;2020</source>. <publisher-loc>Addis Ababa</publisher-loc>: <publisher-name>Federal HIV/AIDS Prevention and Control Office</publisher-name> (<year>2018</year>).</citation></ref>
<ref id="B46"><label>46.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Kim</surname><given-names>MH</given-names></name><name><surname>Ahmed</surname><given-names>S</given-names></name><name><surname>Hosseinipour</surname><given-names>MC</given-names></name><name><surname>Giordano</surname><given-names>TP</given-names></name><name><surname>Chiao</surname><given-names>EY</given-names></name><name><surname>Yu</surname><given-names>X</given-names></name><etal/></person-group> <article-title>Implementation and operational research: the impact of Option B&#x002B; on the antenatal PMTCT cascade in Lilongwe, Malawi</article-title>. <source>J Acquir Immune Defic Syndr</source>. (<year>2015</year>) <volume>68</volume>(<issue>5</issue>):<fpage>e77</fpage>. <pub-id pub-id-type="doi">10.1097/QAI.0000000000000517</pub-id><pub-id pub-id-type="pmid">25585302</pub-id></citation></ref>
<ref id="B47"><label>47.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Iroezi</surname><given-names>ND</given-names></name><name><surname>Mindry</surname><given-names>D</given-names></name><name><surname>Kawale</surname><given-names>P</given-names></name><name><surname>Chikowi</surname><given-names>G</given-names></name><name><surname>Jansen</surname><given-names>PA</given-names></name><name><surname>Hoffman</surname><given-names>RM</given-names></name></person-group>. <article-title>A qualitative analysis of the barriers and facilitators to receiving care in a prevention of mother-to-child program in nkhoma, Malawi</article-title>. <source>J Afr J Reprod Health</source>. (<year>2013</year>) <volume>17</volume>(<issue>4</issue>):<fpage>118</fpage>&#x2013;<lpage>29</lpage>. PMCID: <pub-id pub-id-type="pmcid">PMC4361063</pub-id>.<pub-id pub-id-type="pmid">24689323</pub-id></citation></ref>
<ref id="B48"><label>48.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Megerso</surname><given-names>A</given-names></name><name><surname>Garoma</surname><given-names>S</given-names></name><name><surname>Tolosa Eticha</surname><given-names>TW</given-names></name><name><surname>Daba</surname><given-names>S</given-names></name><name><surname>Tarekegn</surname><given-names>M</given-names></name><name><surname>Habtamu</surname><given-names>Z</given-names></name></person-group>. <article-title>Predictors of loss to follow-up in antiretroviral treatment for adult patients in the Oromia region, Ethiopia</article-title>. <source>J HIV/AIDS</source>. (<year>2016</year>) <volume>8</volume>:<fpage>83</fpage>. PMCID: <pub-id pub-id-type="pmcid">PMC4854271</pub-id></citation></ref>
<ref id="B49"><label>49.</label><citation citation-type="journal"><person-group person-group-type="author"><name><surname>Aliyu</surname><given-names>A</given-names></name><name><surname>Adelekan</surname><given-names>B</given-names></name><name><surname>Andrew</surname><given-names>N</given-names></name><name><surname>Ekong</surname><given-names>E</given-names></name><name><surname>Dapiap</surname><given-names>S</given-names></name><name><surname>Murtala-Ibrahim</surname><given-names>F</given-names></name><etal/></person-group> <article-title>Predictors of loss to follow-up in art experienced patients in Nigeria: a 13-year review (2004&#x2013;2017)</article-title>. <source>BMC AIDS Res Ther</source>. (<year>2019</year>) <volume>16</volume>(<issue>1</issue>):<fpage>30</fpage>. <pub-id pub-id-type="doi">10.1186/s12981-019-0241-3</pub-id></citation></ref></ref-list>
</back>
</article>