Induction of labor and pain: a randomized trial between two vaginal preparations of dinoprostone in nulliparous women with an unfavorable cervix

OBJECTIVE: To compare pain associated with vaginal dinoprostone pessary vs. gel for induction of labor in women with an unfavorable cervix.STUDY DESIGN: A randomized controlled trial in a large academic public general hospital. A total of 52 nulliparous women of gestational age ≥ 38 weeks, with Bishop score ≤ 4 and intact membranes were allocated either to a controlled-release vaginal dinoprostone pessary or repeat doses of vaginal dinoprostone gel. Pain was recorded hourly from early induction until the onset of labor.RESULTS: Mean pain experienced by women belonging to the two groups differed significantly (p < 0.01). Women in the controlled-release device group were also significantly more often severe pain-free than women receiving gel (p < 0.05). Both methods had similar rates of oxytocin infusion and vaginal deliveries.CONCLUSIONS: The two induction procedures should be considered equivalent as far as ripening the cervix and initiating labor. In view of this finding, the low Bishop score should be considered an indication to prefer the controlled-release device, since it reduces pain thereby improving the physical and emotional wellbeing of the parturient.