Clinical parameters for prediction of successful labor induction after application of intravaginal dinoprostone in nulliparous Chinese women

BACKGROUND The aim of this study was to compare the possible clinical parameters for prediction of successful labor induction in Chinese nulliparous women. MATERIAL/METHODS A retrospective, observational trial of labor induction was performed, using a single dose of 10 mg controlled-release dinoprostone for preinduction cervical ripening in 127 nulliparous women (gestational age 38-42 weeks, singleton cephalic presentation). The characteristics of the women with successful labor induction (defined as vaginal delivery achieved on the day of admission; n=80) and failed labor induction (n=47) were compared. RESULTS The main differences observed between the groups were gravidity (P<0.05), induction-active labor interval (5.16±2.98 vs. 8.40±3.41; P<0.05) and birth weight (3421.11±368.14 vs. 3566.36±345.16; P<0.05). Logistic regression demonstrated that gravidity (P<0.05) and induction-active labor interval (P<0.05), but not Bishop score, were significant and independent contributing factors for successful labor induction. In the receiver operating characteristic curves for the prediction of successful labor induction, the best cut-off value for gravidity was 3 (95% confidence interval [CI] 0.64-0.83, P=0.000), and the best cut-off value for the induction-active labor interval was 7.96 (95%CI 0.66-0.85, P=0.000). CONCLUSIONS Less gravidity and shorter induction-active labor interval predict successful labor induction with reasonable accuracy.