OBJECTIVETo investigate the risk factors of pregnancy termination at second and third trimester in women with scarred uterus and placenta previa.

METHODSClinical data of 24 pregnant women of second and third trimester with a scarred uterus and placenta previa,who requested termination in Women's Hospital Zhejiang University School of Medicine from July 2009 to June 2014, were retrospectively analyzed. The method of mifepristone combined with ethacridine lactate was adopted for all cases. Mifepristone combined with ethacridine lactate and uterine artery embolization were routinely given for patients with complete placenta previa. Cesarean section was performed for patients who failed to delivery or underwent massive vaginal bleeding before delivery. Age, gestational weeks, gravidity and parity, times of previous cesarean section, the interval from previous operation, the position and the type of placenta previa, placenta accretet, the indication and method of termination, postpartum hemorrhage, successful rate of labor induction, placental retention ratio and uterus rupture were documented.

RESULTSThe successful rate of labor induction was 83.3%. The analysis showed that age, gestational weeks, gravidity and parity and times of previous cesarean section were not risk factors for failed labor induction, however the interval time from previous operation was related to induction failure (P<0.05). Patients with previous cesarean section ≥ 13 years were more likely to require cesarean section than those <13 years (P<0.05). The placenta adhered to the antetheca of the uterus or placenta accrete increased risk to have cesarean section. There were no significant differences in postpartum hemorrhage, the successful rate of labor induction, placental retention ratio and the rate of uterine rupture between patients with uterine artery embolization and those without.

CONCLUSIONThe labor induction would be feasible for women with a scarred uterus and placenta previa in second and third-trimester pregnancy. The previous operation ≥ 13 years, the antetheca placenta or placenta accrete might increase the incidence of labor induction, while the uterine artery embolization would rise the successful rate of labor induction.