Intravaginal Misoprostol for Cervical Ripening and Labor Induction in Nulliparous Women: A Double-blinded, Prospective Randomized Controlled Study.
BACKGROUND
In China, no multicenter double-blinded prospective randomized controlled study on labor induction has been conducted till now. This study is to evaluate the efficacy and safety of intravaginal accurate 25-μg misoprostol tablets for cervical ripening and labor induction in term pregnancy in nulliparous women.


METHODS
This was a double-blinded, prospective randomized controlled study including nulliparous women from 6 university hospitals across China. Subjects were randomized into misoprostol or placebo group with the sample size ratio set to 7:2. Intravaginal 25-μg misoprostol or placebo was applied at an interval of 4 h (repeated up to 3 times) for labor induction. Primary outcome measures were the incidence of cumulative Bishop score increases ≥3 within 12 h or vaginal delivery within 24 h. Safety assessments included the incidences of maternal morbidity and adverse fetal/neonatal outcomes.


RESULTS
A total of 173 women for misoprostol group and 49 women for placebo were analyzed. The incidence of cumulative Bishop score increases ≥3 within 12 h or vaginal delivery within 24 h was higher in the misoprostol group than in the placebo (64.2% vs. 22.5%, relative risk [RR]: 2.9, 95% confidence interval [CI]: 1.4-6.0). The incidence of onset of labor within 24 h was significantly higher in the misoprostol group than in the placebo group (48.0% vs. 18.4%, RR: 2.6, 95% CI: 1.2-5.7); and the induction-onset of labor interval was significantly shorter in the misoprostol group (P = 0.0003). However, there were no significant differences in the median process time of vaginal labor (6.4 vs. 6.8 h; P = 0.695), incidence (39.3% vs. 49.0%, RR: 0.8, 95% CI: 0.4-1.5) and indications (P = 0.683) of cesarean section deliveries, and frequencies of maternal, fetal/neonatal adverse events between the groups.


CONCLUSIONS
Intravaginal misoprostol 25 μg every 4 h is efficacious and safe in labor induction and cervical ripening.
Yu
Y
Zhang
Hao-Ping
HP
Zhu
Jian-Xia
JX
Fan
Hong
H
Yu
Li-Zhou
LZ
Sun
Lian
L
Chen
Qing
Q
Chang
Nai-Qing
NQ
Zhao
Department of Obstetrics and Gynecology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
Wen
W
Di
D000282:Administration, Intravaginal; D000328:Adult; D020070:Cervical Ripening / Q000187:drug effects*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007751:Labor, Induced / Q000379:methods*; D016595:Misoprostol / Q000008:administration & dosage / Q000627:therapeutic use*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011263:Pregnancy Trimester, Third; D055815:Young Adult
D016595:Misoprostol