Association of Antenatal Corticosteroid Exposure and Infant Survival at 22 and 23 Weeks

In 2014, the leading obstetric societies published an executive summary of a joint workshop to establish obstetric interventions to be considered for periviable births. Antenatal corticosteroid administration between 22^0/7 and 22^6/7 weeks was not recommended given existing evidence. We sought to evaluate whether antenatal steroid exposure was associated with improved survival among resuscitated newborns delivered between 22 and 23 weeks of gestation.

We conducted a population-based cohort study of all resuscitated livebirths delivered between 22^0/7 and 23^6/7 weeks of gestation in the United States during 2009 to 2014 utilizing National Center for Health Statistics data. The primary outcome was rate of survival to 1 year of life (YOL) between infant cohorts based on antenatal steroid exposure. Multivariable logistic regression estimated the association of antenatal steroid exposure on survival outcomes.

In the United States between 2009 and 2014, there were 2,635 and 7,992 infants who received postnatal resuscitation after delivery between 22^0/7 to 22^6/7 and 23^0/7 to 23^6/7 weeks of gestation, respectively. Few infants born at 22 (15.9%) and 23 (26.0%) weeks of gestation received antenatal corticosteroids (ANCS). Among resuscitated neonates, survival to 1 YOL was 45.2 versus 27.8% (adjusted relative risk [aRR]: 1.6, 95% confidence interval [CI]: 1.2-2.1) and 57.9 versus 47.7% (aRR: 1.3, 95% CI: 1.1-1.5) for infants exposed to ANCS compared with those not exposed at 22 and 23 weeks of gestation, respectively. When stratified by 100 g birth weight category, ANCS were associated with survival among neonates weighing 500 to 599 g (aRR: 1.9, 95% CI: 1.3-2.9) and 600 to 699 g (aRR: 1.7, 95% CI: 1.1-2.6) at 22 weeks.

Exposure to ANCS was associated with higher survival rates to 1 YOL among resuscitated infants born at 22 and 23 weeks. National guidelines recommending against ANCS utilization at 22 weeks should be re-evaluated given emerging evidence of benefit.

· Exposure to antenatal steroids was associated with higher survival rates at 22 and 23 weeks of gestation.. · Women exposed to antenatal steroids were more likely to have an adverse outcome.. · The association between steroids and survival was observed among infants with birth weights > 500 g..