[Clinical study on induction of labor with feedback pulsatile oxytocin system]

To improve the safety and the effect on induction of labor with oxytocin.

112 cases were selected for labor induction with feedback pulsatile oxytocin under the monitoring of uterine contraction controller (study group). 112 cases were selected with continuous intravenous infusion of oxytocin as a control (control group). The dose of oxytocin and the pulse time-point were adjusted. The effects of labor induction in the 2 groups were compared.

The most suitable time-point was 1.5 minute after the uterine contraction. The best administration duration was 20 seconds. But the most suitable dose varied individually, generally 12-25 mU. The mean time to establish contraction in study group was significantly shorter (1.9 +/- 1.2 min) than that of the control group (115.5 +/- 72.3 min, P < 0.001). The average dose of oxytocin administered per hour was significantly less in the study group (312 +/- 64 mU) than that of the control group (735 +/- 125 mU, P < 0.001) the success rate was 100% in study group whereas only 90.2% in control group (P < 0.01). The total duration of labor in the study group was 6.9 +/- 4.7 hours in contrast to 20.4 +/- 10.9 hours in the control group (P < 0.001). The occurrences of dystocia, postpartum hemorrhage and neonatal asphyxia were lower in study group.

This study proved that the administration of oxytocin with the feedback pulsatile oxytocin system is easier to establish the effective uterine contraction, and it is a more physiologic and effective regimen for induction of labor.