Regional trends in birth weight in low and middle-income countries 2013–2018

Abstract

Background: Birth weight (BW) is a strong predictor of neonatal outcomes. The purpose of this study was to com‑ pare BWs between global regions (south Asia, sub-Saharan Africa, Central America) prospectively and to determine if trends exist in BW over time using the population-based maternal and newborn registry (MNHR) of the Global Network for Women’sand Children’s Health Research (Global Network). Methods: The MNHR is a prospective observational population-based registryof six research sites participating in the Global Network (2013–2018), within fve low- and middle-income countries (Kenya, Zambia, India, Pakistan, and Guatemala) in threeglobal regions (sub-Saharan Af rica, south Asia, Central America). The birth weights were obtained for all infants born during the study period. This was done either by abstracting from the infants’ health facility records or from direct measurement by the registry staf for infants born at home. After controlling for demographic charac‑ teristics, mixed-efect regression models were utilized to examine regional diferences in birth weights over time. Results: The overall BW meanswere higher for the African sites (Zambia and Kenya), 3186 g (SD 463 g) in 2013 and 3149 g (SD 449 g) in 2018, ascompared to Asian sites (Belagavi and Nagpur, India and Pakistan), 2717 g (SD450 g) in 2013 and 2713 g (SD 452 g) in 2018. The Central American site (Guatemala) had a mean BW intermediate between the African and south Asian sites, 2928 g (SD 452) in 2013, and 2874 g (SD 448) in 2018. The low birth weight (LBW) incidence was highest in the south Asian sites (India and Pakistan) and lowest in the African sites (Kenya and Zambia). The size of regional diferences varied somewhat over time with slight decreases in the gap in birth weights between the African and Asian sites and slight increases in the gap between the African and Central American sites. Conclusions: Overall, BWmeans by global region did not change signifcantly over the 5-year study period. From 2013 to 2018, infants enrolled at the African sites demonstrated the highest BW means overall across the entire study period, particularly as compared to Asian sites. The incidence of LBW was highest in the Asian sites (India and Paki‑ stan) compared to the African and Central American sites.