PRENATAL CORTICOSTEROID TREATMENT AND ACC ELERATED FETAL PULMONARY MATURATION .1. EXPERIMENTAL AND PHARMACOLOGICAL BASIS

Data from numerous experimental studies clearly indicate that endogeno us corticosteroids physiologically act on the fetal lung maturation. T here are also convincing experimental data demonstrating that exogenou s corticosteroids stimulate phospholipids biosynthesis, induce the sur factant specific protein genes expression, and improve the lung biophy sical properties. The first report of a clinical beneficial effect der ived from these experimental observations is due to Liggins and Howie who demonstrated that prenatal corticosteroid treatment significantly reduces the incidence of respiratory distress syndrome and the mortali ty among preterm neonates. Fluorinated corticosteroids (dexamethasone, betamethasone) are the only efficient corticosteroids, with the advan tage of a low mineralocorticoid activity After a single course, they d o not inhibit postnatal stress adrenal response; however, repealed cou rses may induce adrenal depression if a stressing event occurs after b irth.