Global and temporal trends in neonatal and under-five mortality due to birth asphyxia/trauma and prematurity (2000-2021) with projections up to 2040.

backgroundDespite substantial global progress in reducing neonatal mortality, the deceleration in neonatal mortality decline in many low- and middle-income countries threatens attainment of Sustainable Development Goal 3.2. Intrapartum-related events and complications of preterm birth remain the leading causes of neonatal deaths. Therefore, this study aimed to examine temporal trends in neonatal and under-five mortality due to birth asphyxia, trauma, and prematurity from 2000 to 2021, with projections to 2040.

methodsThis study used the United Nations Inter-agency Group for Child Mortality Estimation (UN IGME) cause-of-death dataset, which provides standardized annual estimates of under-five and neonatal mortality from birth asphyxia/trauma and prematurity for 194 countries and territories between 2000 and 2021. Causes of death were defined according to the dataset's standardized classification. Country-specific mortality trends were examined in relation to four country-level indicators (the Socio-demographic Index, Human Development Index, Universal Health Coverage service coverage index, and Healthcare Access and Quality Index) using regression analyses. Temporal trends in cause-specific mortality were quantified using the estimated annual percentage change, and future mortality through 2040 was projected under three scenarios: (1) current-trend; (2) regional best-performer; (3) high-income country convergence based on country-specific annual rates of reduction.

resultsGlobally, neonatal mortality declined from 7.52 deaths per 1000 live births [90% uncertainty interval (90% UI): 7.13-7.88] to 4.18 (3.81-4.82) for birth asphyxia/trauma, and from 10.63 (10.05-11.33) to 6.49 (6.05-7.38) for prematurity between 2000 and 2021. West and Central Africa and Eastern and Southern Africa had the highest neonatal mortality in 2021 and achieved the slowest progress, whereas East Asia and Pacific and Eastern Europe and Central Asia had the most pronounced declines. Countries with lower sociodemographic and health system indicator values showed slower declines in mortality, while the greatest reductions were observed in those with intermediate-to-upper levels. Projections suggest that disparities could remain substantial by 2040 if current trends continue, although accelerated progress in high-burden regions could yield further reductions.

conclusionDespite substantial progress since 2000, neonatal mortality from birth asphyxia/trauma and prematurity remains persistently high, particularly in Africa, but scenario analyses suggest that substantial reductions could be achieved if future declines follow trajectories observed in the best-performing settings.