Unresolved issues on the antenatal use of corticosteroids for fetal lung maturation

Antenatal corticosteroids (ACS) for fetal lung maturation is celebrating the 50th anniversary. The most recent Cochrane review concluded that there is robust evidence that a single course of ACS reduces the risk of perinatal death and respiratory distress syndrome. Some aspects of ACS remain unresolved, including variations in the steroids regimen, effectiveness in certain groups, long-term effects, optimal timing of ACS administration in elective cases. it is well established that a single course of betamethasone or dexamethasone is beneficial in cases of anticipated preterm birth and delivery eventually occurs between two and seven days from administration. The main focus for future research should be on limiting the unnecessary exposure in low-risk pregnancies and investigating the effect in specific groups, periviable and late preterm fetuses.