2. Delayed pushing: Women assigned to the delayed pushing group will be instructed to wait for 60 minutes from complete cervical dilation before pushing. Women will be allowed to push earlier if they feel an irresistible urge to push or there is a clinical indication to initiate pushing. We chose 60 minutes as the delay time because our meta-analysis suggested that the duration of delay (ranging from 60 to 180 minutes) did not modify the effect of delayed pushing on spontaneous vaginal delivery rates. Additionally, a 60-minute delay will enable us to assess the effect of delayed pushing without unduly increasing total duration of the second stage. This is important because, although there is no established threshold, a number of large cohort studies suggest incremental increase in the risks of operative delivery, maternal infection, hemorrhage, and laceration, as well as neonatal Apgar score depression, worsening cord pH, and neonatal morbidity, with each additional hour in the second stage, regardless of whether patients pushed immediately or delayed pushing. Finally, patients indicated in our survey that they would prefer to wait no longer than 60 minutes after complete cervical dilation before pushing if they were randomized to the delayed pushing group.