Intracervical prostaglandins are effective compared to placebo, but appear inferior when compared to intravaginal prostaglandins.
Prostaglandin E2 for cervical ripening: a randomized comparison of Cervidil versus Prepidil.
Our purpose was to compare the efficacy and safety of two standardized preparations of prostaglandin E2, Prepidil and Cervidil, for ripening of the cervix and initiation of labor.
                This was a prospective randomized study. Subjects in whom induction of labor was indicated were randomly assigned to receive either Prepidil (n = 36), an intracervical prostaglandin E2 gel, or Cervidil (n = 37), a controlled-release hydrogel pessary, as a cervical ripening agent. Inclusion criteria included (1) a Bishop score of < or = 7, (2) a cervix < 4 cm dilated, and (3) < or = 2 cm of cervical dilatation if effacement was > 70%. Each agent was administered according to the manufacturer's recommendations.
                There was no difference in Bishop scores between the two groups at the completion of the ripening process. The following mean times were shorter for the pessary group than for the gel group: (1) insertion of the ripening agent to vaginal delivery (20.6 vs 26.4 hours, p = 0.017), (2) time to achieve cervical ripening (11.1 vs 15.2 hours, p < 0.001), (3) time to achieve active labor (18.3 vs 25.5 hours, p = 0.019), and (4) hospital stay (3.7 vs 4.4 days, p = 0.03). Labor was initiated without the use of oxytocin in 24% of patients in the pessary group versus 3% of those in the gel group (p = 0.014).
                Both prostaglandin E2 agents are effective in achieving cervical ripening; however, the controlled-release pessary achieves ripening over a shorter time period. Furthermore, because time to achieve vaginal delivery and length of stay are shorter, the use of oxytocin is less frequent, and there is no increase in complications, the overall cost is expected to be less with the use of Cervidil as compared with Prepidil.