Abstract： Objective To investigate safety and efficacy of dinoprostone suppositories(0.8 mm) used in cervical ripening and labor induction in women with term premature rupture of the membranes.Methods One hundred women of term monocyesis with premature rupture of the membranes,head presentation,bishop score less than 6(test group)and 180 women with intact fetal membranes(control group)were enrolled into this multicenter,prospective clinical study.The vaginal delivery system was inserted into the posterior foruix,and the patients were recumbent for 2 hours after insertion.The interval time from using dinoprostone suppositories to uterine contraction,to labor and delivery were recorded.The following index were also recorded and compared,including the mean inserted time of dinoprostone suppositories,fetal heart beat,meconium stained amniotic fluid,hyperstimulation of uterus and the other complications,mode of delivery,stage of labor,postpartum hemorrhage,status of neonates.Results Three cases intest group and 23 casesin control group weren't in labor within 24 hours.The rate of labor within 24 hours in test group was significant higher than that in control group(97.0% vs.87.2%,P<0.01).It was observed that 73 cases undergoing vaginal deliveries(75.3%,73/97)and 24 cases undergoing cesarean section dehveries(24.7%,24/97)in test group and 107 cases undergoing vaginal delivery(68.2%,107/157)and 50 cases undergoing cesarean section delivery(31.8%,50/157)in control group,when compared the rate of vaginal or cesarean section deliveries between two group,it didn't reach statistical difference (P >0. 05). It had no significant difference in the interval time from using dinoprostone suppositories to labor starting and the mean inserted time and the total labor time between two groups ( P > 0.05 ). The incidence of uterine tachysystole was 11.3% (11/97) in test group and 19. 1% (30/157) in control group (P>0. 05), which did not reach statistical difference (P>0. 05). There wasn't neonatal asphyxia in both groups. Conclusion It was safe and efficient to use dinoprostone suppositories for cervical ripening and induction of term pregnancy with premature rupture of the membranes, however, monitoring should be intensified.