Antenatal corticosteroid therapy: current strategies and identifying mediators and markers for response.

Landmark early work has led to the nearly universal use of antenatal corticosteroids to accelerate fetal lung maturity with pregnancies complicated by impending preterm birth. Antenatal corticosteroids clearly reduce respiratory morbidity, death, and other adverse neonatal outcomes. Limited pregnant human pharmacokinetic data and some animal data give clinicians some information as to the behavior of the drug in the body. However, there is controversy about the type, amount, and frequency of steroid to use for this therapy. This review article summarizes the history, clinical use, and pharmacology of antenatal steroids. In addition, the review highlights some potential mediators of steroid response and current research strategies aimed at possible optimization of this therapy.