Uterine hyperstimulation in cervical ripening with oral misoprostol versus dinoprostone vaginal pessary: A real-life single-center descriptive study.

Background: Cervical ripening is recommended in the event of an unfavorable cervix but carries a risk of uterine hyperstimulation, a serious complication of induction associated with maternal and fetal morbidity. To evaluate the incidence of uterine hyperstimulation following cervical ripening with oral misoprostol versus dinoprostone vaginal pessary.

Methods: We conducted a retrospective cohort study of all deliveries in 2020 in the maternity department of a tertiary hospital involving women with a singleton cephalic presentation who underwent labor induction with cervical ripening by oral misoprostol or dinoprostone vaginal pessary.

Results: Four hundred and thirty-nine cervical ripening procedures were included in the study, 285 with oral misoprostol and 154 with dinoprostone vaginal pessary. In univariate analysis, uterine tachysystole was significantly less frequent with oral misoprostol (15/285 cases, 5.3 %) than with dinoprostone pessary (26/154 cases, 17.2 %; p < 0.01), as was uterine tachysystole with fetal heart rate abnormalities (3/285 cases, 1.1 % versus 8/154 cases, 5.2 %; p = 0.02). Using multivariable analysis, the odds of uterine tachysystole were significantly lower in the oral misoprostol group than in the dinoprostone pessary group (odds ratio (OR), 0.28; 95 % confidence interval (CI) [0.13; 0.55]; p < 0.01), as were the odds of uterine tachysystole with fetal heart rate abnormalities (OR, 0.19, 95 % CI [0.04; 0.68], p < 0.01).

Conclusions: In this group of women, uterine tachysystole and uterine tachysystole with fetal heart rate abnormalities occurred less frequently after cervical ripening with oral misoprostol than after ripening with a dinoprostone pessary.