A prospective randomized evaluation of a hygroscopic cervical dilator, Dilapan, in the preinduction ripening of patients undergoing induction of labor

OBJECTIVE: Our purpose was to investigate the safety and efficacy of a synthetic intracervical hygroscopic dilator Dilapan (Gynotech, Inc., Middlesex, N.J.), on ripening the cervix before medically indicated induction of labor. STUDY DESIGN: Two hundred forty patients with a Bishop score of less than or equal to 4 were prospectively randomized to receive either preinduction synthetic hygroscopic dilators (n = 112) or no pretreatment (n = 128) before oxytocin induction. RESULTS: Compared with controls, the dilator group exhibited a significant change in median Bishop score, but there was no significant difference in length of labor (dilator 18.8 +/- 12.8 hours vs control 21.7 +/- 14.8 hours) or in the cesarean section rate (dilator 41/112 [36.6%] vs control 49/128 [38.3%]). Relative proportions of nulliparous and multiparous patients, infant weights, and cervical dilation at the time of cesarean section were not significantly different between groups. No adverse maternal or fetal effects could be attributed to use of the device. CONCLUSIONS: Preinduction cervical ripening with hygroscopic dilators does not shorten the length of labor or lower the cesarean section rate in patients undergoing induction of labor.