Efficacy of sublingual misoprostol for induction of labor at term and post term according to parity and membrane integrity: a prospective observational study

Abstract

Objective: To evaluate the effectiveness and safety of 25 mcg sublingual misoprostol for induction of Labor at term according to parity and membrane integrity.

Methods: We conducted a prospective observational study on singleton pregnancies undergoing induction of Labor at term. Twenty-five mcg of misoprostol were administered sublingually every 4 h. Main outcomes were vaginal deliveries within 24 h, time-to-vaginal-delivery, hyper-stimulation syndrome, cesarean section rate, arterial pH< 7.0 and NICU admission rate.

Results: We studied 508 patients, 375 nulliparous and 133 multiparous women. Sixty-five percent and 78%, respectively, delivered vaginally within 24 h from first administration. Median time-to-vaginal-delivery was significantly shorter in PROM than in women with intact membranes (p < 0.001). Epidural analgesia prolonged time-to-vaginal-delivery among nulliparous women (p < 0.0005). A positive correlation between BMI and time to delivery was observed in both nulliparous and multiparous women (p < 0.05). Cesarean section rate was 22% in nulliparous and 6% in multiparous group. Induction failure was 1.4% and uterine hyper-stimulation 1%. No pH≤ 7.00 was recorded; overall 7 (1.4%) newborns were admitted to NICU.

Conclusions: Sublingually administered misoprostol is an effective and safe method for induction of Labor at term. Parity, status of membranes and BMI significantly affect time to delivery.

Keywords:

• Induction of labor
• membrane status
• parity
• sublingual misoprostol

Acknowledgements

We are in debt with all doctors and midwife who consistently and prudently applied the clinical protocol of our Unit, and with all the women who permitted to use these clinical data.

Declaration of interest

There were not any personal, political, intellectual or religious interest, or financial gains involved in this study.