Based on our sample size calculation, we will need at least 160 patients in each arm of the study to find an increase in the cesarean delivery rate from 25% to 40% in women who undergo induction of labor where oxytocin is discontinued once the active phase of labor begins. This sample size calculation uses a power of 80% and an alpha level (statistical significance) of 0.05. The baseline rate of cesarean in the US is 25-30%. We chose 40% as a significantly increased rate of CS since this rate would represent a 60% increase in CS from the baseline risk in the population.