Globally, about 20.5 million newborn infants were born with birthweights <2,500 g in 2015, 90% of whom were from low-and middle-income countries (LMICs) (1, 2). Nearly half of under 5 deaths are among neonates (infants <28 days old) (3). Eighty percent of neonatal deaths occur in low birthweight (LBW) infants, which includes both preterm infants born before 37 completed weeks gestational age and infants who are small for gestational age (SGA) i.e., weight <10th percentile for gestational age. Preterm birth is the single most important cause of death in the neonatal period accounting for up to a million neonatal deaths annually (2, 4, 5). Amongst LBW infants, very low birth weight (VLBW; 1,000 g to <1,500 g), and very preterm (born 28 to <32 weeks gestational age) are even more at risk, with higher incidences of late onset sepsis (LOS), necrotising enterocolitis (NEC), feeding intolerance and ultimately, mortality (6, 7).

Optimizing early nutrition in very preterm and VLBW neonates has the potential to improve their survival, growth, neurodevelopment, and long-term health outcomes. Early feeding strategies for preterm infants vary widely across the world and, although optimal postnatal growth rates have not been established, there is a general consensus to aim for a gestation-equivalent fetal growth rate (8). Noteworthy is that preterm infants have higher nutritional requirements than term infants. To achieve this, an energy intake of 110 to 135 Kcal/kg/day and protein intake of 3.5 to 4 g/kg/day in VLBW infants is recommended (9). Failure to meet recommended nutrient intakes results in poor growth and is associated with increased short-term risks such as LOS and predisposes them to long-term neurodevelopmental impairment and adult onset metabolic and cardiovascular disease (8, 10–12).

The majority of available evidence on feeding strategies in hospitalized very preterm/VLBW infants is derived from high income countries (HICs) with limited data from sub-Saharan Africa (sSA) (13). The implementation of recommended strategies is fraught with challenges in the context of resource limitations, a common problem in sSA. Early initiation of enteral feeds and exclusive feeding with breastmilk and fortification of human milk for hospitalized very preterm/VLBW babies is common in high income countries due to the availability of breastmilk banks and fortifiers, which are not available in most centers in sSA (14). In addition, early parenteral nutrition used in HICs, to provide the necessary nutrients whilst full enteral feeds are established, is not widely available and affordable in most of sSA.

In 2011, in recognition of these challenges in LMICs, the World Health Organization (WHO) emphasized early and exclusive breastmilk for preterm babies with formula supplementation only in infants with sub-optimal growth trajectories (15), by which stage key periods for brain growth and differentiation may have been missed. Evidence-based feeding guidelines require high quality research and are essential in resource constrained settings. To achieve this, it is essential to collect data on existing feeding practices.

We conducted a survey to describe feeding practices in hospitalized very preterm/VLBW infants among neonatal care practitioners in Nigeria and Kenya as part of the Neonatal Nutrition Network project (https://www.lstmed.ac.uk/nnu), to identify the diverse challenges and mitigating factors in the context of limited resources. These data will inform the prioritization and design of guidelines and interventions to optimize nutrition in these vulnerable infants in sSA.

A total of 152 questionnaires were sent out, 48 in Nigeria and 104 in Kenya. A total of 50 were returned representing 37 (74.0%) different hospitals in Nigeria and 13 (26.0%) in Kenya. Table 1 shows the distribution of the centers according to level of health care provided.

This survey of enteral feeding practices for very preterm and/or VLBW babies at secondary and tertiary levels of health care in Nigeria and Kenya shows very wide variations in practice within and between both countries. Although all of the units initiated feeds using expressed breast milk, only about half initiate feeding within the first 24 h and some not until after 72 h. This marked variability in practice likely accounts for the equally marked variation between units in time to reach full feeds.

Most units routinely checked gastric residual volume before oral and/or nasal tube feeding. Other modes of feeding utilized were cup, cup and spoon, and bottle. None of the units had access to donor breast milk. Formula feeds, breast milk fortifiers and wet nurses (in Nigeria only) were used to supplement shortfalls in expressed breast milk. In addition, probiotics, and nutritional supplements (folic acid, iron, calcium, and phosphorus) were widely administered. Few of the units used buccal colostrum.

Written feeding guidelines were in use in 45.9 and 85.6% of the Nigerian and Kenyan units, respectively. The use of standardized feeding protocols in middle and high income countries (18–20), is associated with earlier achievement of full enteral feeds (thus shorter use of vascular catheters), and reduced rates of neonatal sepsis, NEC, extrauterine growth restriction, and overall, decreased length of stay in the hospital. However, variations in feeding practices across units also occur in high income countries depending on a number of factors including access to facilities such as breastmilk banks (21, 22). Currently there is little research on preterm feeding practices in sSA to inform feeding protocols for these at-risk infants (13). Kenya has a national guideline for feeding these vulnerable infants (23). In Nigeria, guidelines for comprehensive newborn care in secondary and tertiary hospitals were launched on 25th November, 2021 (24). This occurred after this survey was done, thus less than half of the centers in Nigeria had unit protocols for preterm feeding. Though this study did not evaluate the degree to which facilities adhered to their protocols, it has highlighted strengths and opportunities to build on as well weaknesses and threats or challenges to address in order to successfully implement a national guideline or protocol. The implementation of national guidelines would present an opportunity for evaluation and comparison of preterm feeding across a large number of neonatal units.

The overall aim of feeding guidelines/protocols for these at-risk infants is to achieve full enteral feeds in the shortest possible time and safely, to promote immediate and long-term health. An overview of systematic reviews of feeding practices for VLBW infants in sSA (13) showed research gaps related to optimal time to starting feeds, what to feed, what volume to start with, how to advance, best mode of feeding and what supplements to use. All these practices must take into account what facilities and support are available and sustainable particularly in systems where care is paid for out of pocket.

Few units practiced administration of buccal or oropharyngeal colostrum despite this being a low-cost procedure that is being increasingly adopted in high income settings with the potential to reduce time to full enteral feeds (25). This may reflect the length of time needed for research findings to be incorporated into clinical guidelines and routine practice, the first publication dating from 2009 (26). Most units started enteral feeding with trophic feeds ranging between 10 and 20 ml/kg/day, with daily advancements of 10–20 ml/kg/day, though there is evidence from developed countries that faster advancement of 30–40 ml/kg/day may be safe and facilitates earlier attainment of full enteral feeds (8, 27) few of the units in this survey advanced more than 20 ml/kg/day. The WHO feeding guidelines for preterm infants recommend a daily increase “up to” 30 ml/kg for LMICs (14) and this may be the reason for the observed practice. The fact that the clinical status of the infants in sSA and the level of monitoring and nursing care might not be similar to those in high income countries, coupled with the suboptimal nutritional, economic and overall conditions of mothers as well as the health system set up (28) may all intricately interact to interfere with lactation, milk expression and storage and feeding regimens in these units. The WHO recommendation needs to be evaluated for infants in this region.

Multicentre studies in Africa need to factor in the particular challenges with resources such as donor breastmilk banks, with evaluation of different implementation models such as in South Africa (23). The first human breastmilk bank in Kenya commenced in Nairobi in 2019 with a view to scaling up. This process took 3 years from planning to eventual inauguration (29). No donor milk bank exists in Nigeria which may be related to resource constraints and/or cultural and religious factors. Some centers, however, utilized wet nursing to provide breastmilk. It will be informative to conduct research into the cultural acceptability and extent of this practice as well as safety particularly in the context of novel and evolving infectious diseases, as this may prove a useful and affordable alternative to breastmilk banking.

Feeding practices in very preterm/VLBW infants vary widely in Nigeria and Kenya possibly due to a complete lack of locally generated evidence to guide practice. High quality research into feeding of very preterm/VLBW infants, that is sensitive to the context of limited human resources, technology, and consumables, is urgently needed to inform the development of guidelines appropriate to these settings.

Isa Abdulkadir (Ahmadu Bello University, Zaria, Nigeria); Ismaela Abubakar (Liverpool School of Tropical Medicine, Liverpool, UK); Abimbola E. Akindolire (College of Medicine, University of Ibadan, Nigeria); Olusegun Akinyinka (College of Medicine, University of Ibadan, Nigeria); Stephen J. Allen (Liverpool School of Tropical Medicine, Liverpool, UK); Pauline E. A. Andang'o (Maseno University, Kenya); Graham Devereux (Liverpool School of Tropical Medicine, Liverpool, UK); Chinyere Ezeaka (College of Medicine, University of Lagos/Lagos University Teaching Hospital, Nigeria); Beatrice N. Ezenwa (College of Medicine, University of Lagos/ Lagos University Teaching Hospital, Nigeria); Iretiola B. Fajolu (College of Medicine, University of Lagos/ Lagos University Teaching Hospital, Nigeria); Zainab O. Imam (Lagos State University Teaching Hospital, Lagos, Nigeria); Kevin Mortimer (Liverpool School of Tropical Medicine, Liverpool, UK); Martha K. Mwangome (KEMRI Wellcome Trust Research Programme, Kilifi, Kenya); Helen M. Nabwera (Liverpool School of Tropical Medicine, Liverpool, UK); Grace M. Nalwa (Jaramogi Oginga Odinga Teaching and Referral Hospital, Kisumu, Kenya & Maseno University, Kenya); Walter Otieno (Jaramogi Oginga Odinga Teaching and Referral Hospital, Kisumu, Kenya & Maseno University, Kenya); Macrine A. Olwala (Jaramogi Oginga Odinga Teaching and Referral Hospital, Kisumu, Kenya); Alison W. Talbert (KEMRI Wellcome Trust Research Programme, Kilifi, Kenya); Nicholas D. Embleton (Newcastle University, Newcastle, UK); Olukemi O. Tongo (College of Medicine, University of Ibadan, Nigeria); Dominic D. Umoru (Maitama District Hospital, Abuja, Nigeria); Janneke van de Wijgert (University of Liverpool, Liverpool, UK); Melissa Gladstone (University of Liverpool, Liverpool, UK).

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

OT contributed to conception and design of the study and the first draft of the manuscript. MO and AT were co-authors. All authors contributed to manuscript revision, read, and approved the submitted version.

This work was supported by an MRC Confidence in Global Nutrition and Health Research Initiative grant Improving the survival, growth and development of low birthweight newborns through better nutrition MC_PC_MR/R-19789/1.

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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