Pregnancy and neonatal outcomes of term deliveries of singleton pregnancies at different gestations in Sri Lanka: a multicentre prospective study.

Background: Delivery at 'term' is considered low risk for mothers and neonates. Evidence suggests variable outcomes at different gestations, even within 'term'. This study aims to compare pregnancy characteristics and neonatal outcomes of delivery at different gestations at 'term'. Methods: We analysed the data of the island-wide multicentre Sri Lanka Birth Weight Study, which recruited all live-born newborns in 13 hospitals over 2 months in 2023. Only data of singleton pregnancies and term neonates were included. Pregnancy complications and neonatal outcomes of each gestation were analysed by logistic regression. Findings: 8053 'term' singleton deliveries (1805, 2367, 2087, 1762, and 32 at 37, 38, 39, 40 and 41 weeks) were included. A higher proportion of mothers delivering at 37 weeks had pregestational diabetes (AOR: 7.84, 95% CI: 4.24-14.37), chronic hypertension (AOR: 4.37, 95% CI: 2.01-9.49), pregnancy-induced hypertension (AOR: 2.65, 95% CI: 1.92-3.66) and gestational diabetes (AOR: 1.96, 95% CI: 1.57-2.44) compared to mothers delivering at 39 weeks. The elective caesarean section rate was highest at 37 weeks (783, 43.4%) compared to 38 weeks (737, 31.1%) or higher gestations. Delivery at 37 weeks was associated with inferior neonatal outcomes of 5-min APGAR <8 (AOR: 3.04, 95% CI: 1.36-6.76), requiring resuscitation (AOR: 1.74, 95% CI: 1.27-2.38) and admission to intensive care (AOR: 1.62, 95% CI: 1.09-2.41) compared to 38 weeks. Interpretation: Neonates born at 38 weeks showed better outcomes than those born at 37 weeks. When elective delivery is necessary, postponing it from 37 weeks to at least 38 weeks would positively impact neonatal outcomes. Funding: UNICEF, Sri Lanka, funded the Sri Lanka Birth Weight Study. No funding obtained for this manuscript.