To investigate the effect of initiating labor by oxytocin infusion on the outcome of delivery in cephalic presentation, the dystocia rate and final modes of delivery were analyzed in 3,090 cases of head presentation using oxytocin infusion and 2,982 cases with spontaneous onset of labor as control group. The results showed that 562 of the cases using oxytocin developed cephalic dystocia, a rate of 18.2%, while 371(12.4%) of the control group had dystocia. Besides, cephalic dystocia, rates of episiotomy, vacuum extraction and cesarean section were all significantly higher in the oxytocin group than those in the control (P < 0.005). Data also showed that the higher dosage, the more frequency and the longer time of pitocin infusion the higher the rate of dystocia.