Investigators from multiple institutions conducted a retrospective study to evaluate the effectiveness of antenatal corticosteroids administered to pregnant women prior to 23 weeks’ gestation in improving survival, and survival without major morbidities, in infants born at 22 0/7 to 23 6/7 weeks’ gestation. For the study, data from the extremely preterm infant registry of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NICHD NRN) were reviewed. This database includes demographic, clinical, and outcome information on mothers and their infants. For the current study, participants were infants born between 2016 and 2019 at a gestational age ≥22 0/7 and <24 0/7 weeks. Infants whose mothers received corticosteroids at ≥23 weeks were excluded, as were those who died within 12 hours of birth without receiving postnatal life support. Study participants were categorized as receiving full antenatal corticosteroids if their mother received 2 intramuscular doses of betamethasone, partial antenatal corticosteroids if 1 dose was administered, or no antenatal corticosteroids. The primary study outcome was survival to hospital discharge, and the main secondary outcome was survival without severe morbidities, including grade 3 or 4 intracranial hemorrhage, necrotizing enterocolitis requiring surgery, retinopathy of prematurity requiring treatment, cystic periventricular leukomalacia, and bronchopulmonary dysplasia requiring mechanical ventilation at 36 weeks’ gestation. Logistic regression was used to assess the association between the outcomes and exposure to full, partial, or no antenatal corticosteroids, after adjusting for multiple covariates.
Data on 431 neonates born at a mean gestational age of 22.6 ±0.5 weeks were analyzed. Among these study participants, 110 (25.5%) received no antenatal corticosteroids, 80 (18.6%) received partial, and 241 (55.9%) full antenatal corticosteroids. The median birth weights of infants in these groups were 54 g, 530 g, and 549 g, respectively. Among infants exposed to full antenatal corticosteroids, 130 (53.9%) survived until discharge, compared to 30 (37.5%) and 239 (35.5%), respectively, of those receiving partial or no antenatal corticosteroids. After adjusting for multiple confounders, infants receiving full treatment were more likely to survive than those not receiving antenatal corticosteroids (OR, 1.95; 95% CI, 1.07, 3.56); there was no significant difference in survival between those receiving full and those receiving partial antenatal corticosteroids (OR, 1.39; 95% CI, 0.71, 2.72). The proportion of infants surviving without major morbidities were 26.9%, 12.8%, and 10.0%, respectively, for those receiving full, partial, or no antenatal corticosteroids. Compared to those receiving no antenatal steroids, infants with full treatment were significantly more likely to survive without major morbidities (OR, 2.74; 95% CI, 1.19, 6.30).
The authors conclude that full treatment with antenatal corticosteroids before 23 weeks’ gestation was associated with higher rates of survival, and survival without major morbidities, in infants born between 22 0/7 and 23 6/7 weeks...