Antenatal Corticosteroids at the Limits of Fetal Viability

Faced with threatened extreme preterm delivery, clinicians and parents must decide whether to intervene, given poor outcomes of such infants. Data are lacking on the efficacy of antenatal corticosteroids administered at the limits of fetal viability. To examine benefits of maternal corticosteroid administration, investigators conducted a large observational cohort study among 10,541 infants born at 22 to 25 weeks' gestation at one of several National Institute of Child Health and Human Development Neonatal Research Network centers from 1993 through 2009. Three quarters of infants were born to mothers who received antenatal steroids (“exposed” infants). Infants who died postnatally within the first 12 hours without having received neonatal resuscitation were excluded.

Nonblack women of higher socioeconomic status who were older than 19 and those who underwent cesarean deliveries were more likely to have received steroids. Exposed infants were less likely to die by age 18 to 22 months, even after adjustment for maternal sociodemographic and clinical factors (37% vs. 57%; adjusted odds ratio, 0.6). This benefit was noted among infants born at 23 to 25 weeks' gestation but not earlier. Exposed infants also were less likely to have neurodevelopmental impairment at ages 18 to 22 months (39% vs. 49%; AOR, 0.8).