Antenatal corticosteroids for maturity of term or near term fetuses: systematic review and meta-analysis of randomized controlled trials

OBJECTIVE: To evaluate the effectiveness of antenatal corticosteroids given at ≥34 weeks' gestation. DESIGN: Systematic review with meta-analysis. DATA SOURCES: Electronic databases were searched from their inception to February 2016. ELIGIBILITY CRITERIA FOR STUDY SELECTION: weeks) and trials given before planned cesarean delivery at term (≥37 weeks) were included. DATA SYNTHESIS: The primary outcome was the incidence of severe respiratory distress syndrome (RDS). The summary measures were reported as relative risks or mean differences with 95% confidence intervals. RESULTS: weeks' gestation had a significantly lower incidence of transient tachypnea of the newborn (relative risk 0.72, 95% confidence interval 0.56 to 0.92), severe RDS (0.60, 0.33 to 0.94), and use of surfactant (0.61, 0.38 to 0.99). Infants of mothers undergoing planned cesarean delivery at ≥37 weeks' gestation who received prophylactic antenatal corticosteroids 48 hours before delivery had a significantly lower risk of RDS (0.40, 0.27 to 0.59), mild RDS (0.43, 0.26 to 0.72), moderate RDS (0.40, 0.18 to 0.88), transient tachypnea of the newborn (0.38, 0.25 to 0.57), and mechanical ventilation (0.19, 0.08 to 0.43), and significantly less time receiving oxygen (mean difference -2.06 hours, 95% confidence interval -2.17 to -1.95), lower percentage of maximum inspired oxygen concentration (-0.66%, -0.69% to -0.63%), shorter stay in neonatal intensive care (-7.44 days, -7.44 to -7.43), and a higher APGAR score at one and at five minutes. CONCLUSIONS: weeks' gestation, as well as for women undergoing planned cesarean delivery at ≥37 weeks' gestation. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42016035234.