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

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.