Is More Than One Dose of Misoprostol Needed to Expedite Vaginal Delivery in a Patient With an Unripe Cervix?

This study involves a comparison of two different regimens of prostaglandin use for "cervical ripening" prior to induction of labor. Women admitted to the hospital for induction of labor who are found to have "unripe" cervixes at the time of admission, and who agree to participate in the study will be randomly assigned to one of two treatment groups. In one group, a single dose of 25 µcg of misoprostol will be administered vaginally and four hours later oxytocin induction will be started if clinically indicated. In the second group of women, repeat doses of misoprostol will be given every four hours up to six doses unless labor or cervical ripening occurs sooner. At this point, oxytocin will be started as needed. Success of vaginal delivery by 24 hours, time from initiation of protocol to delivery and cesarean section rates will be compared. Complications such as postpartum hemorrhage, episodes of tachysystole with fetal compromise and chorioamnionitis and endometritis will be monitored.

Inclusion criteria

• Any pregnant woman undergoing induction of labor
• Live singleton pregnancy ≥ 37 week gestation
• Bishop score < 6
• Category I fetal heart rate

Exclusion criteria

• Contraindications to vaginal delivery (e.g. vasa previa, placenta prevue,non-vertex presentation, umbilical cord prolapse, and active genital herpes infection.)
• Pregnancies complicated by major fetal anomalies
• Any contraindication to the use of misoprostol, including
• History of previous c-section or major uterine surgery
• Prior allergic reaction
• Category II or III fetal heart rate
• Regular uterine contractions ≥ 3 in a 10-minute period persistent for at least 30 minutes
• Estimated fetal weight < 10 percentile
• Premature rupture of membranes
• Age < 18 years old
• Women who do not have the capacity to consent