Multicenter, randomized, controlled trial of delayed pushing for nulliparous women in the second stage of labor with continuous epidural analgesia

OBJECTIVE: This study was undertaken to determine whether a policy of delayed pushing for nulliparous women with continuous-infusion epidural analgesia reduces the risk of difficult delivery (cesarean delivery, operative delivery from a midpelvic position, low-pelvic procedures with relation >45 degrees). STUDY DESIGN: In this multicenter, randomized, controlled trial women in the delayed pushing group (n = 936) were advised to wait greater than or equal to 2 hours after full dilatation before commencement of pushing. Women in the early pushing group (n = 926) were advised to commence pushing as soon as they had been randomly assigned. RESULTS: Difficult delivery was reduced with delayed pushing (relative risk, 0.79; 9556 confidence interval, 0.66-0.95). The greatest effect was on midpelvic procedures (relative risk, 0.72; 95% confidence interval, 0.55-0.93). Although there was little evidence for an effect on low-pelvic procedures, spontaneous delivery was more frequent among women who practiced delayed pushing (relative risk, 1.09; 95% confidence interval, 1.00-1.18). Abnormal umbilical cord blood pH (<7.15 venous value or <7.10 arterial value) was more frequent in the delayed pushing group (relative risk, 2.45, 95% confidence interval, 1.35-4.43). However, scores for a summary indicator, the Neonatal Morbidity Index, were similarly distributed in the 2 groups. CONCLUSION: Delayed pushing is an effective strategy to reduce difficult deliveries among nulliparous women.