Vergleich des Cook-Katheters in der Geburtseinleitung mit anschließender Gabe entweder von Oxytocin intravenös oder mit Prostaglandingel intravaginal oder einer Kombination aus beidem bei Frauen mit Zustand nach Kaiserschnitt

The aim of this study was to compare the Cook catheter in labor induction followed by administration of either Oxytocin i.v. or with vaginal Prostaglandin gel, or a combination of both, in women with a previous caesarean section. As a result, it is expected that more evidence-based recommendations can be made in the future for the best induction procedure in patients with prior caesarean section for planned vaginal births. To date, the Cook Medical double-balloon catheter (Cook Medical, Cervical Ripening Balloon; Cook OB/GYN, Bloomington, Indiana, USA) is still in Off- Label-Use for labor induction in patients with a prior caesarean section. The Cook catheter may prove a notable method in reducing caesarean sections in the future as a mechanical delivery induction method because of its good efficacy in comparison to other methods (Prostaglandin gel intravaginally and Oxytocin i.v.) with an overall low risk of maternal or fetal complications. Currently, the rate of caesarean section is much higher than the recommended rates sanctioned by the WHO. Therefore, it becomes clear that alternative means are necessary to reduce caesarean sections. High rates of caesarean section may cause several complications that can be reduced by a focus on trial of labor after caesarean section (TOLAC) with achievement of a vaginal birth after caesarean section (VBAC). Directives for a trial of labor after caesarean section (TOLAC) may also reduce the incidence of repeat caesarean sections, as they have a relatively high success rate of 70-76%. Patients were recruited from 2018 to 2022 (March). A total of 89 patients were enrolled in the study. Group 1 consisting of the patients at whom vaginal Prostaglandin gel and the Cook catheter were used. Group 2 consisting of the patients at whom Oxytocin i.v. and the Cook catheter were used. Group 3 included all patients at whom all three procedures were used in combination. The primary study outcome was the rate of recurring caesarean section. Secondary study outcomes were induction-to-delivery interval in minutes, vaginal birth rate, failed inductions, and several others. Statistical significance for all analyses was defined as p ≤ 0.05. All variables were tested for significance using adequate statistical procedures. The different cohorts were mostly homogeneous with respect to demographic data. The only difference could be observed in group 2, which demonstrated a significantly higher gestational age and Bishop score compared with the other groups. Indications for labor induction were the same between the groups. Caesarean section rate showed no significant difference between the groups (p = 0.664). Also, no difference was evident with respect to vaginal deliveries (p = 0.664) or assisted vaginal deliveries (p = 0.067). Induction-to-delivery interval was significantly lower in group 1 (p = 0.002) and group 2 (p = 0.048) than in group 3. More vaginal deliveries within 24 hours were evident in group 2 than in the remaining groups (p = 0.041 and p = 0.02). In contrast, group 3 showed significantly more failed inductions of labor than group 2 (p = 0.045). Abnormal CTG was observed more frequently in group 2 (p = 0.045). Epidural anesthesia was used significantly more often in group 3. Otherwise, no other significant differences with respect to the outcome could be detected. The study outcomes are mostly reflected in similar data from related literature. The shorter induction-to-delivery interval in group 2 seems logical due to the initially higher Bishop score and the use of Oxytocin i.v., which may also explain the higher rate of vaginal deliveries within 24 hours in this group and the increased rate of failed induction attempts in group 3 compared with group 2. These and also the other differences between the groups must be interpreted with caution due to the small cohort size. Overall, a study with multiple limitations was conducted. In order to obtain more valid data, further studies on this topic should be conducted in the future that include a larger patient population and thus have fewer structural deficiencies in the study design. Nevertheless, the value of this study lies in the fact that it is one of the first to address different insertion procedures combined with the Cook catheter.