Adolescence is a period of major developmental transitions, marked by physiological, physical and emotional changes, and the acquisition of advanced impulse regulation (1). Together, these changes have a profound influence on adolescent's decision making, risk taking, and social relationships (1). Adolescence is also a critical period for romantic and sexual development, and across the world, adolescents are known to become sexually active and gain diverse sexual experiences (2). As elsewhere, a significant proportion of adolescents in Nigeria are sexually active, and the sexual conduct of adolescents in Nigeria has similarly attracted public health concerns, particularly because of the high prevalence of unsafe sex, mainly condomless sex among this age group (3).

Sex without a condom is the major unsafe practice which exposes adolescents to various risks, such as unintended pregnancy, early child birth and unsafe abortion, and also puts them at a high risk of contracting sexually transmitted infections (STIs), including HIV (4, 5). Adolescent pregnancy is a public health challenge in Africa, and adolescent pregnancies are one of the major reasons for the high rate of maternal mortality in Nigeria (6). A systematic review and meta-analysis estimated a pooled adolescent pregnancy rate of 18.8% in Africa, 19.3% in Sub-Saharan African, and 15.9% in Nigeria (6). Recent data has shown an upward trajectory in the rates of STIs, notably gonorrhea, chlamydia, and human papilloma virus infection among adolescents and young people (7). While the HIV epidemic appears to be decreasing in Nigeria and other African countries, this gain is limited and there is evidence that HIV prevalence is still high among adolescents and young people and AIDS remains a leading cause of mortality among young people in Africa (7, 8).

Condom use, which is one of the most cost effective protective measures against unintended pregnancy and STI/HIV is underpinned by complex factors. Research has found that social, economic and cultural factors are related to condomless sex (9–13). Gender dynamics are important drivers of non-condom use because of the inability of both partners to openly communicate safe sex, due to the power differences that exist between males and females in Africa (14). Also, early sexual initiation, having multiple sexual partners and intergenerational sex, that is, a sexual relationship with an older partner are factors found to be associated with inconsistent condom use among adolescents in some studies (15, 16). In many cases, sex with older partners is transactional, in exchange for material, money and other benefits. In Nigeria, transactional sex is a common practice among adolescent girls as well as boys, and this poses a challenge for adolescents to negotiate protective options such as consistent (i.e., at every sexual intercourse) condom use (9, 17, 18). Aside the challenge adolescents have negotiating condom use with older partners; consistent condom use is linked to adolescent's (lack of) awareness/knowledge of SRH issues, and risk perception regarding STIs, HIV, and pregnancy (19–21). Research in several sub-Sahara African countries (e.g., Nigeria, South-Africa, Zimbabwe, Mozambique) found that adolescent's low perceived risk of HIV or other STIs contributes significantly to their likelihood of not (consistently) using a condom during sexual intercourse (22–25).

The risk perception may also be due to lack of adequate knowledge on sexual and reproductive health matters subsequent to poor communication between parents and adolescents on sexuality issues (26). Like in many African countries, adolescent sexual behavior is a sensitive matter in the context of dominant religion and culture (27, 28).

Parents in Nigeria sometimes deny adolescent involvement in sex outside marriage and typically adhere to strict, traditional discipline in the upbringing of their children that makes it difficult to accept that adolescents may have sex (29). In contrast, most adolescents are exposed to information about sex through the Internet (27), and frequently engage in (unsafe) sex (2, 27). Although the Nigerian government made a commitment to provide ASRH services to address adolescent's sexual and reproductive health issues, these services are often not available–and when they are, they are of low quality and do not meet adolescent's needs (30).

As most young people become sexually active in adolescence, including in Nigeria, it is important to prevent adverse outcomes and promote the sexual health and well-being of adolescents. This study therefore aimed to assess the sexual experiences of adolescents in Plateau State, Nigeria, and to examine socio-demographic characteristics and awareness of SRH issues, knowledge of prevention of SRH problems, and perceived risk of SRH problems as covariates of their sexual activity and safe sex practices, specifically consistent condom use. The findings from this study may inform governmental policy development and decision-making regarding the provision and implementation of adolescent sexual and reproductive health care services across Nigeria.

Young people in Nigeria are at risk of several sexual and reproductive health problems such as unintended pregnancy, STIs, and HIV (6). Therefore, the aims of the current study were to assess the sexual experiences of adolescent boys and girls in Plateau State, Nigeria, to understand the factors that influence their sexual activity, and to determine the most significant covariates of (in)consistent condom use. The latter is an important contributing factor for mitigating the health risks these young people are exposed to.

Our results show that although the majority had sexual partners of the opposite sex, few of the adolescents had same sex partners. In addition, more than three quarter of the sexually active adolescents were not consistently using condoms during sex. This is especially concerning because more than half of our respondents indicated a low risk perception for unintended pregnancies or disease transmission. Further, almost half of the adolescents had a low level of awareness of SRH issues and poor knowledge of how to prevent pregnancy, STI and HIV. These findings are corroborated by similar studies, for example, a meta-analysis of research in sub-Saharan African countries and Nigeria reported high rates of sexual activity and multiple sexual partners among adolescents males and females, as well as a large age difference between adolescents and their sexual partners (32–34). Also, studies conducted among adolescents in Nigeria have reported inconsistent use of condoms during sex, as well as a low risk perception and lack of knowledge of SRH issues and how to prevent SRH problems (11, 12, 22).

Our results show that older adolescents were five times likely to be sexually active than younger ones, adolescents out of school were twice as likely to be sexually active than those in school, and males were more likely to be sexually active than females. This is in line with studies conducted in the western and Eastern part of Nigeria (35, 36). Moreover, gender (i.e., being male) was an important factor linked to the sexual activity of adolescents in three consecutive demographic and health surveys in Nigeria (34). Some studies have also linked the role of gender in sexual activity especially in Africa to the patriarchal norms; where males are seen as superior to females and permitted by society to always have their ways, this dominant role exert influence on their sexual behavior (1, 37).

Factors found to be associated with inconsistent condom use in this study were a lower level of education and having sex with older partners: Adolescents with a lower level of education were twice as likely to have inconsistent condom use during sex compared to those with a higher education, while those who reported to have sexual partners within their own age group were more likely to consistently use a condom during sex. Similarly, some studies have documented inconsistent condom use among adolescents in relationship with older partners; the younger partners usually find it difficult to persuade the older partners especially when the partners are unwilling to use condom (37–39). However, the one unique covariate of consistent condom use in this study is gender; the adolescent males were more likely to consistently use condom during sex than the female adolescents. Similar to our finding is the results from studies in some African countries and across Nigeria, which also reported more condomless sex among females, attributing it to gender inequality which does not encourage free dialogue and communication between partners (37, 40–42).

One of the strength of this study is the privacy and confidentiality provided during data collection. Specifically, were the research assistances that were their age group that gave the respondents the freedom to provide information on their sexual life more freely. Furthermore, the diversity of the adolescents (males and females, in-school and out of school, lower education and higher education) in this study gave a broader perspective of the sexual experiences and the factors influencing condom use among adolescents. The study however did not capture the younger adolescents, mainly due to ethical reasons around consent when conducting studies among younger adolescents, thereby limiting our understanding of the particular experiences and challenges of this younger group of adolescents. We are also not ruling out recall bias from self-reporting and social desirability bias in reporting sexual activity though they were asked to be honest in their responses and assured of confidentiality.

In this study, we found that a good number of adolescents were sexually active with diverse experiences. Both male and female adolescents had multiple sexual partners and some had same sex partners. The majority of the sexually active adolescents had low risk perception and were not consistently using condom during sex. We also found that more than half of the adolescents had low risk perception of getting pregnant/becoming infected with STI or HIV during unprotected sex and about half were not aware of SRH issues. Gender was seen to significantly influence safe sex, specifically being male, was the independent covariate for being sexually active and for consistent condom use.We recommend that more sexual health promotion activities geared toward safe sex practices be targeted at both in school and out of school adolescents. In addition, gender should be mainstreamed into ASRH programmes to ensure a better and healthier sexual experience among adolescents.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving human participants were reviewed and approved by Jos University Teaching Hospital (JUTH) Research Ethics Committee. The patients/participants provided their written informed consent to participate in this study.

All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.

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.

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