Antenatal corticosteroids in the management of preterm birth: are we back where we started?

Though the preterm birth rate in the United States has finally begun to decline, preterm birth remains a critical public health problem. The administration of antenatal corticosteroids to improve outcomes after preterm birth is one of the most important interventions in obstetrics. This article summarizes the evidence for antenatal corticosteroid efficacy and safety that has accumulated since Graham Liggins and Ross Howie first introduced this therapy. Although antenatal corticosteroids have proven effective for singleton pregnancies at risk for preterm birth between 26 and 34 weeks’ gestation, questions remain about the utility in specific patient populations such as multiple gestations, very early preterm gestations, and pregnancies complicated by IUGR. In addition, there is still uncertainty about the length of corticosteroid effectiveness and the need for repeat or rescue courses. Though a significant amount of data has accumulated on antenatal corticosteroids over the past 40 years, more information is still needed to refine the use of this therapy and improve outcomes for these at-risk patients.