A randomized controlled trial of oxytocin administered at the end of the second stage of labor versus oxytocin administered at the end of the third stage of labor in the prevention of postpartum hemorrhage.

The general objective was to determine the incidence of postpartum hemorrhage when oxytocin was administered at the end of the second stage of labor compared to when oxytocin was administered at the end of the third stage. The specific objectives were to determine the mean amount of blood loss, duration of the third stage of labor, need for additional uterotonics and blood transfusion, incidence of hypotension and retained placenta, and mean difference in hemoglobin levels. A randomized controlled trial was conducted in a tertiary care training hospital. 130 women with term, singleton, live pregnancies in cephalic presentation who delivered vaginally were included. Patients were randomly allocated to receive oxytocin after the second stage or after the third stage of labor. Oxytocin was administered as a continuous intravenous infusion. The placenta was delivered by controlled cord traction after placental separation. Blood loss was measured by weight, and the corresponding volume was computed. Relative risk was calculated. Incidence of postpartum hemorrhage, volume of blood loss, duration of the third stage of labor, need for additional uterotonics and blood transfusion, incidence of hypotension and retained placenta, and difference in hemoglobin levels were the main outcome measures. There was a decreased incidence of postpartum hemorrhage (39.66% vs. 48.61%, relative risk [RR] = 0.82, 95% confidence interval [CI] = 0.55-1.21) and less amount of blood loss (557.93 ml vs. 636.84 ml, p = 0.352) when oxytocin was administered at the end of the second stage of labor. There was less need for additional uterotonics (12.07% vs. 13.89%, RR = 0.87, 95% CI = 0.35-2.14), and blood transfusion (5.17% vs. 5.56%, RR = 0.87, 95% CI = 0.22-3.99). There was a smaller mean difference in hemoglobin (16.20 g/dl vs. 20.29 g/dl, p = 0.145). Mean duration of the third stage of labor were comparable (7.93 minutes vs. 7.96 minutes, p = 0.863). However, more patients developed hypotension (3.45% vs. 1.39%, RR = 2.48, 95% CI = 0.23-26.70). All results were not statistically significant. There was no incidence of retained placenta. There is a trend towards a reduction of the risk of postpartum hemorrhage when oxytocin is administered at the end of the second stage of labor. This is not accompanied by an increased risk for any morbidity.