In a prospective randomized study, 560 pregnant women were subjected to labor induction with continuous or pulsed intravenous oxytocin infusion. There were no significant differences with respect to maternal history, Bishop score and perinatal morbidity. The mean induction to delivery interval was shorter in the pulsed infusion group than in the continuous infusion group (325 +/- 63 vs 433 +/- 67 min in primiparous, p < 0.001 and 204 +/- 52 vs 236 +/- 87 min in multiparous women, p < 0.01). The mean amount of oxytocin administered in the pulsed infusion group was also significantly lower than in the continuous infusion group (4.7 +/- 0.6 mU/min versus 9.6 +/- 3.4 mU/min in primiparous, p < 0.001 and 2.1 +/- 0.4 mU/min versus 5.2 +/- 2.3 mU/min in multiparous women, p < 0.001). Our study demonstrates that pulsatile administration of oxytocin is as safe as continuous intravenous infusion, requires less oxytocin and is more effective as it reduces labor duration.