Abstract: Objective：To investigate the effects of inducing labor by different position of vaginal balloon with cervical dilatation double-balloon. Methods: Sixty full-term primiparous woman who delivered in department of obstetrics of Henan People′s Hospital were selected as the observation objects. 30 patients of observation group were induced with vaginal balloon inside the cervix（group A）, and the other 30 patients were induced by outside the cervix（group B）randomly. Then the induced outcome and the fetal outcomes of the two groups were compared. Results: The cervical Bishop scores，the cervical flatness，cervical opening rate and the 24-hour birth rate of group A were higher than group B，and the differences were statistically significant （all P＜0.05）. The first labor time and the total delivery process of group A were shorter than group B, the differences were statistically significant （both P＜0.05）. There was no significant difference in cesarean section rate, newborn weight, discomfort score and neonatal asphyxia rate（P＞0.05）. Conclusions: When induced with cervical dilatation double-balloon, placing the vaginal balloon inside the cervix can shorten the first and total delivery process.

Key words: Labor, induced, Vaginal balloon, Inside the cervix, Outside the cervix, Cervix uteri