Propess versus prostin for induction of labour in term primiparous women.

Background: The rate of induction of labour has increased over the decades and numerous medications are available in the market. This study compares the efficacy and safety between dinoprostone slow-release pessary (Propess) and dinoprostone tablet (Prostin) for labour induction at term in nulliparous women.

Methods: This was a prospective single-blind randomized controlled trial conducted in a tertiary medical centre in Taiwan from September 1, 2020 to February 28, 2021. We recruited nulliparous women at term with a singleton pregnancy, fetus in cephalic presentation, an unfavourable cervix, and the cervical length had been measured by transvaginal sonography three times during labour induction. The main outcomes are duration from induction of labour to vaginal delivery, vaginal delivery rate, maternal and neonatal complication rates.

Results: In both groups, Prostin and Propess, 30 pregnant women were enrolled. The Propess group had higher vaginal delivery rate but it did not meet statistically significant difference. The Prostin group had significantly higher rate of adding oxytocin for augmentation (p = 0.0002). No significant difference was observed in either labouring course, maternal or neonatal outcomes. The probability of vaginal delivery was independently related to the cervical length measured by transvaginal sonography 8 h after Prostin or Propess administration as well as neonatal birth weight.

Conclusion: Both Prostin and Propess can be used as cervical ripening agents with similar efficacy and without significant morbidity. Propess administration was associated with higher vaginal delivery rate and less need to add oxytocin. Intrapartum measurement of cervical length is helpful in predicting successful vaginal delivery.