Objective To investigate the effectiveness of COOK balloon on induced laboring in high-risk pregnant women.Methods A total of 140 high-risk pregnant women in a Xinxiang hospital from January 2015 to June2019 were selected as study objects and divided into the observation group（n=70）and the control group（n=70）according to the random digits table.The oxytocin was used in the control group

while the COOK balloon was used in the observation group.Cervical Bishop scores before and after 12 hof COOK balloon or oxytocin in two groups were compared;laboring period

total laboring stage

forceps delivery rate

uterine-incision delivery rate and spontaneous delivery rate in two groups were compared;complications of cervical laceration

postpartum fever

postpartum hemorrhage

vaginal hematoma

uterine over-efficiency and gastrointestinal symptom in two groups were compared.Results After intervention of 12 h

Bishop score in the observation group was（6.98±1.09）

which was higher than that of（6.16±1.02）in the control group

with statistically significant differences（P<0.05）.Laboring period in the observation group was（13.49±2.30）h

which was shorter than that of（16.87±2.51）h

with statistically significant differences（P<0.05）.Comparison of forceps delivery rate

uterine-incision delivery rate and spontaneous delivery rate in two groups had no statistically significant differences（P>0.05）.Complications in the observation group was 12.86%

which was lower than that of 41.43%in the control group

with statistically significant differences（P<0.05）.Conclusion Application of COOK balloon in high-risk pregnant women can effectively promote the cervical ripening

shorten the induction time and avoid the adverse drug reactions

which has high safety and is worth of clinical promotion.