Neonatal Outcomes Following Antenatal Corticosteroid Exposure in Term Deliveries

Objective Antenatal corticosteroids are one of the most widely accepted interventions for preventing short-term complications related to premature birth prior to 34 weeks. We conducted this study to evaluate the impact of antenatal corticosteroid (ACS) administration on neonatal outcomes in neonates born at term, (37 weeks to 42 weeks). Study Design: This retrospective cohort study used data from the National Center for Health Statistics Vital Statistics database, which includes linked birth and infant death records for all births in the United States from 2016 to 2021. Singleton, non-anomalous pregnancies delivered between 37- and 42-weeks’ gestation were included. The primary outcomes studied included infant mortality, APGAR score < 3 at 5 minutes, neonatal seizures, and need for ventilation > 6 hours. The exposure of interest was antenatal corticosteroid administration during pregnancy. Univariate and multivariate logistic regression analyses were conducted to evaluate the association between ACS exposure and neonatal outcomes, adjusting for relevant confounders including small for gestational age (SGA), hypertensive disorders, preeclampsia, pregestational diabetes and cesarean delivery. Results Among the total 23,45,173 births included in the analysis, 153,289 (0.65%) were exposed to antenatal corticosteroids (ACS). Infant mortality was significantly higher in the ACS-exposed group compared with the unexposed group (0.36% vs 0.17%; adjusted odds ratio [aOR], 1.92; 95% confidence interval [CI], 1.76–2.10; P < 0.0001). The highest risks were observed at 38 weeks (aOR, 1.65; 95% CI, 1.37–1.98) and 39 weeks (aOR, 1.82; 95% CI, 1.50–2.20). ACS exposure was also associated with increased odds of a 5- minute APGAR score < 3 (0.42% vs 0.26%; aOR, 1.39; 95% CI, 1.27–1.51), need for ventilation > 6 hours (1.78% vs 0.54%; aOR, 2.78; 95% CI, 2.67–2.90) and neonatal seizures (0.05% vs 0.03%; aOR, 1.59; 95% CI, 1.25–2.01). Conclusions Antenatal corticosteroids exposure at term was associated with nearly a twofold increase in the risk of infant mortality, as well as increased odds of respiratory and neurologic complications. These findings highlight the importance of judicious use of ACS in pregnancies likely to result in term delivery and support further investigation into its potential adverse effects in this population.