Impact of antenatal corticosteroids on postnatal growth of infants born between 23 and 29 weeks of gestation

Abstract Objective: To assess the effect of antenatal corticosteroids on postnatal growth in infants born at 23-29 weeks’ gestation. Study Design: This study used data from the Pediatrix Clinical Data Warehouse to emulate a target trial, in which inverse propensity weighting (IPW) was used to balance pre-treatment confounders. Maternal-infant dyads from 2018 to 2020 were included. Primary outcomes included postnatal weight, length, and head circumference growth trajectory percentiles. Result: The unadjusted cohort consisted of 11,912 dyads. After IPW adjustment, there were 23,231 dyads. Exposed infants showed higher postnatal trajectory percentiles for weight (by 3.4%), length (by 1.8%), and head circumference (by 2.5%) when compared to non-exposed infants. The positive effect of antenatal corticosteroids on postnatal growth was only observed among infants without exposure to preeclampsia/eclampsia/HELLP syndrome or fetal growth restriction. Conclusion: Antenatal corticosteroid exposure is associated with better postnatal growth. The study is limited by its retrospective nature.