Association of Antenatal Corticosteroids and Magnesium Sulfate Therapy With Neurodevelopmental Outcome in Extremely Preterm Children.

OBJECTIVE: To test the primary hypothesis that extremely preterm children antenatally exposed to both magnesium sulfate and antenatal corticosteroids have a lower rate of severe neurodevelopmental impairment or death compared with those exposed to antenatal corticosteroids alone.

METHODS: This was a prospective observational study of children born at 22 0/7-26 6/7 weeks of gestation from 2011 to 2014 at Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network hospitals (N=3,093). The primary outcome was severe neurodevelopmental impairment or death at 18-26 months of corrected age follow-up based on exposure to antenatal corticosteroids and magnesium sulfate or antenatal corticosteroids alone. Secondary outcomes included components of severe neurodevelopmental impairment by exposure group and comparisons of severe neurodevelopmental impairment or death between children exposed to both antenatal corticosteroids and magnesium sulfate with those exposed to magnesium sulfate alone or to neither antenatal corticosteroids nor magnesium sulfate. Logistic regression models adjusted for background characteristics.

RESULTS: Children exposed to both antenatal corticosteroids and magnesium sulfate had a lower rate of severe neurodevelopmental impairment or death (813/2,239, 36.3%) compared with those exposed to antenatal corticosteroids alone (225/508, 44.3%; adjusted odds ratio [aOR] 0.73; 95% CI 0.58-0.91), magnesium sulfate alone (47/89, 53%; aOR 0.49; 95% CI 0.29-0.82), or neither therapy (121/251; 48.2%; aOR 0.66, 95% CI 0.49-0.89). Similarly, children exposed to both antenatal corticosteroids and magnesium sulfate had a lower rate of death compared with either or neither therapy, but the rate of severe neurodevelopmental impairment among survivors did not differ between exposure groups.

CONCLUSION: In children born between 22 0/7 and 26 6/7 weeks of gestation, exposure to both antenatal corticosteroids and magnesium sulfate was associated with lower rates of severe neurodevelopmental impairment or death and death compared with exposure to antenatal corticosteroids alone.

CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT00063063.