ReviewEffects of antenatal glucocorticoids on the developing brain

- Antenatal GC therapy provides significant reduction in fetal morbidity and mortality.
- Benefit may be limited in certain gestational ages.
- Controversy continues to exist in the optimal regimen for delivery and administration.
- The future of ACS must include pathways for the individual fetus rather than population based approach in order to improve outcomes.

Glucocorticoids (GCs) regulate distinct physiological processes in the developing fetus, in particular accelerating organ maturation that enables the fetus to survive outside the womb. In preterm birth, the developing fetus does not receive sufficient exposure to endogenous GCs in utero for proper organ development predisposing the neonate to complications including intraventricular hemorrhage, respiratory distress syndrome (RDS) and necrotizing enterocolitis (NEC). Synthetic GCs (sGCs) have proven useful in the prevention of these complications since they are able to promote the rapid maturation of underdeveloped organs present in the fetus. While these drugs have proven to be clinically effective in the prevention of IVH, RDS and NEC, they may also trigger adverse developmental side effects. This review will examine the current clinical use of antenatal sGC therapy in preterm birth, their placental metabolism, and their effects on the developing brain.