276 Neonatal outcomes in patients exposed to late preterm steroids following publication of SMFM recommendations

Abstract

In 2016, the Society for Maternal Fetal Medicine (SMFM) released recommendations for the use of antenatal late preterm steroids. The purpose of this study is to evaluate neonatal outcomes in a nonclinical trial setting following SMFM antenatal late preterm steroid guidance. We conducted a multi-center, retrospective study of deliveries from October 2016 to December 2019. Singletons that were exposed to antenatal corticosteroids between 34 0/7 weeks and 36 6/7 weeks gestation in accordance with SMFM recommendations were compared to a control group of unexposed neonates matched for gestational age at delivery, delivery method, delivery hospital, fetal sex, maternal race/ethnicity, and pregnancy complications including obesity, fetal growth restriction, gestational diabetes, hypertensive disease, and substance abuse. Patients with multiple gestations, preexisting diabetes, and patients that were exposed to antenatal corticosteroids outside the late preterm period were excluded. 1156 pregnancies met inclusion criteria and were matched with 1156 controls. The rate of hypoglycemia in neonates exposed to late preterm steroids was 28.6%, compared to 18.9% in the unexposed group (p <0.001 OR 1.72, CI [1.41 , 2.10]). NICU admission rates were higher in the exposed group (33.1% vs 21.6%, p <0.001, OR 1.80, CI [1.48 , 2.17]). Need for CPAP was higher in the steroid exposed group (9.1% vs 6.5%, p=0.02, OR 1.44, CI [1.05 , 1.99]). A longer length of hospital stay was noted in exposed neonates (117 vs 95 hours, p <0.001, CI [12.2 , 32.1]). No differences were noted in mechanical ventilation, surfactant administration, hyperbilirubinemia, or neonatal death. Despite promising results in the ALPS trial, no benefits were observed in neonates exposed to antenatal late preterm steroids in accordance with SMFM recommendations. Exposed neonates were more likely to experience hypoglycemia, NICU admission, and longer length of hospital stay. Larger, geographically diverse studies are needed to evaluate the effects of antenatal corticosteroids in the late preterm period.