Antenatal Corticosteroids at 21-23 Weeks of Gestation.

Neonates born at the cusp of viability are at particularly high risk of severe morbidity and mortality. With advances in medicine and technology, the ability to resuscitate smaller, more premature neonates has become possible, and survival as early as 21 weeks of gestation has been reported. Although administration of antenatal corticosteroids has been shown to reduce the risk of morbidity and mortality at later gestational ages, neonates born before 24 weeks of gestation have not been included in randomized clinical trials. Changing clinical practices surrounding neonatal resuscitation with intervention offered after birth at earlier gestational ages has prompted re-evaluation of the use of antenatal corticosteroids at these very early gestational ages. Recent observational data demonstrate that antenatal corticosteroids administered before deliveries at or after 22 weeks of gestation are associated with lower risks of neonatal mortality, although survival with severe morbidity remains high. Future research is needed to determine the efficacy of antenatal corticosteroids for deliveries before 22 weeks of gestation and should evaluate the timing of corticosteroid administration. Furthermore, efforts should be made to include diverse populations and clinically meaningful long-term outcomes. At this time, the decision surrounding antenatal corticosteroids for threatened periviable deliveries should incorporate multidisciplinary counseling with the goal of achieving concordant prenatal and postnatal management aligned with the patient's desires.