Mortality rate-dependent variations in antenatal corticosteroid-associated outcomes in very low birth weight infants with 23-34 weeks of gestation: A nationwide cohort study.

Antenatal corticosteroid (ACS) administration has been known as one of the most effective treatment in perinatal medicine, but the beneficial effects of ACS may vary not only gestational age, but also the quality of perinatal and neonatal care of the institution. This nationwide cohort study of the Korean Neonatal Network (KNN) data was consisted of <1,500g infants born at 23-34 weeks at 67 KNN hospitals between 2013 and 2017. The 9,142 eligible infants were assigned into two groups-group 1 and 2