Intracervical misoprostol as an effective method of labor induction at term

Abstract

Objects: The purpose of this study was to evaluate the safety and effectiveness of intracervical misoprostol for the induction of labor at term. Methods: Eighty-nine term pregnancies requiring induction of labor were treated intracervically with 50 μg of misoprostol. The dose was repeated every 4 h until adequate uterine contraction and cervical dilatation were achieved. Status of cervical ripening, uterine contraction, cervical dilatation, labor course and side effects were recorded and analyzed. Results: Among the 89 patients, 58 had an unfavorable cervix (Bishop score ≤4) and 31 had a favorable cervix (Bishop score >4). Labor was successfully induced in all cases, most (93.3%) of which required a single dose of misoprostol. Seventy-two patients (81%) proceeded to spontaneous vaginal delivery, and 61 (85%) deliveries were achieved within 12 h. The other 17 cases received cesarean delivery with indications of fetopelvic disproportion (six cases), failure of induction (seven cases) and acute fetal distress (four cases). The mean duration from induction to regular uterine contraction and to delivery was 483±537 min and 79.2±38.2 min, respectively, with no significant difference between the two groups with differing status of cervical ripening. Complications of uterine contraction, including tachysystole (15 cases), hypertonus (one case) and hyperstimulation (10 cases) were more common in the group of unfavorable cervix (45%) than that of favorable cervix (23%) ( P<0.05). Conclusion: In addition to the oral and intravaginal routes of administration, intracervical misoprostol at a single dose of 50 μg appears to be an effective method for induction of labor at term, but caution should be taken with cases with unfavorable cervix.