Timing of antenatal corticosteroids is important for extremely preterm infants' survival.

Multiple courses of ACS are associated with a dose-dependent decline in foetal growth, which may affect later development and health.

No abstract

(BJOG 2017;124:1567–1574) Antenatal corticosteroid (ACS) treatment is recommended for all women who are at risk of preterm birth before 34 weeks’ gestation and reduces neonatal death, respiratory distress syndrome, intraventricular hemorrhage, and other adverse events in preterm infants. Data regarding the effects of ACS on extremely preterm infants is limited. This study aimed to investigate the impact of the administration-to-birth time interval on survival in extremely preterm infants.

Although this study indicates that repeat exposure to antenatal corticosteroids may have an impact on aspects of executive functioning, it does not provide support for the prevailing concern that such fetal exposure will have a major adverse impact on cognitive functions and psychological health later in life.