Mortality from birth through adolescence: Trends, Determinants, and Insights from a Longitudinal Cohort in Benin

Introduction Despite substantial global progress, child mortality remains a major public health burden, with sub-Saharan Africa disproportionately affected. In West Africa, deaths from preventable causes remain alarmingly high, yet longitudinal evidence on the rates and risk factors of child mortality in the region is scarce. This study is among the first in Benin to examine child mortality from birth to 14 years in a community-based, longitudinal cohort. Methods Data originate from the Malaria in Pregnancy Preventive Alternative Drugs (MiPPAD) trial (NCT00811421), an open-label, randomized controlled trial that recruited pregnant women in their second trimester across four sub-Saharan African countries between September 2009 and December 2012. This analysis uses data from 1183 women enrolled at three health centers in the semi-rural Allada district of Benin, with offspring follow-up at 1, 9, and 12 months, 6 years, and 13-14 years. Results Among 1093 live births, 99 deaths were recorded between birth and 14 years of follow-up, alongside 44 stillbirths and 10 spontaneous abortions. The majority of deaths occurred within the first six years of life: 22 (22.2%) in the neonatal period, 34 (34.3%) between 28 days and 12 months, and 37 (37.4%) between one and six years, with only 6 (6.1%) deaths between six and 14 years. Respiratory distress was the predominant cause of neonatal death (81%), with half of those babies having low birthweight (<2500 g). Beyond 28 days, malaria became the leading cause, accounting for 45% of deaths between 28 days and 14 years. In adjusted analyses, having a previous live birth was associated with reduced overall mortality (RR 0.52, 95% CI 0.29, 0.94) while low birthweight (<2500 grams) was associated with elevated risk (RR 2.32, 95% CI 1.44, 3.73). Discussion and Conclusions Child mortality in this semi-rural Beninese cohort was concentrated in early life and driven primarily by respiratory distress in the neonatal period and malaria thereafter. These findings underscore the need for strengthened neonatal care infrastructure, expanded preterm birth support, and scaled-up malaria prevention strategies targeting young children -- priorities critical for advancing progress toward SDG 3.2 in West Africa.