Pre-cervical ripening and hygroscopic cervical dilators in pre-labor induction.

Introduction: Induction of labor (IOL) is becoming a universal topic in Obstetrics, when the risk of continuing a pregnancy outweighs the benefits. Preinduction is a more recent tool to prepare the cervix when the BISHOP-score is low. About one-third of IOL cases require cervical ripening, which is the physical softening, thinning, and dilation of the cervix in preparation for labor and birth. We report a single center experience regarding the use of hygroscopic dilators in the pre-labor phase to obtain cervical ripening before labor induction.

Materials & Methods: We conducted a retrospective observational study comparing patient records from the Gynecology and Obstetrics Unit in "Santo Stefano" Hospital in Prato, Tuscany. The inclusion criteria for participants were women who had undergone pre-labor induction because of a BISHOP-score < 3. The gestational age of all the pregnant women was at term (> 37 weeks).

Results: From January 2022 to April 2022, a total of 581 women delivered at term of gestational age at the Gynecology and Obstetrics Unit in "Santo Stefano" Hospital. Cervical ripening was necessary for 82 women with a Bishop score < 3 and hygroscopic cervical dilators were used in 35/82 (42.7%) patients. All patients showed a change in Bishop-score upon removal of the dilators. All 35 patients (100%) reported an increase in terms of consistency and dilation of the cervix but not in terms of length. None of the patients reported discomfort during the 24 h that they kept the hygroscopic dilators in place. No patients reported uterine tachysystole on cardiotocographic tracing, vaginal bleeding, rupture of membranes or cervical tears.

Conclusions: Our results are in line with those in the literature, demonstrating the validity of hygroscopic dilators in cervical maturation of pregnancies at term and their efficacy was again highlighted in terms of both maternal and fetal safety and patient satisfaction.