Tugging the Foley catheter balloon every three hours in induction of labor after one previous cesarean: a randomized controlled trial

Abstract

BACKGROUND

Induction of labor after 1 previous cesarean delivery with an unripe cervix have an especially high risk for unplanned cesarean delivery and uterine rupture. Mechanical balloon ripening is often preferred over prostaglandin-based ripening during induction of labor after 1 previous cesarean delivery, because uterine rupture has been associated with prostaglandin use. The transcervical Foley balloon can be dislodged past the ripened cervix and be retained comfortably in the vagina during passive placement. Tugging of the Foley catheter can be a noninvasive and tolerated method for timelier retrieval of the retained balloon; expediting discovery of a ripened cervix would permit an earlier follow-on amniotomy and oxytocin infusion, thereby hastening birth.

OBJECTIVE

This study aimed to evaluate the effect of tugging of the Foley balloon for 30 seconds every 3 hours during 12 hours of scheduled placement in comparison with standard care (no tugging) on the induction to birth interval and patient satisfaction.

STUDY DESIGN

This randomized controlled trial, conducted at a university hospital in Malaysia, recruited participants from April 2023 to March 2024. Eligible participants admitted for Foley balloon induction of labor who had 1 previous cesarean were recruited. After balloon insertion, participants were randomized to tugging or standard care. Following balloon displacement, a vaginal examination was performed to check the cervix. The examination findings then dictated the follow-on management of induction of labor after 1 previous cesarean according to standard practice. The primary outcomes were the induction (Foley insertion) to delivery interval and participants’ satisfaction with the birthing process. Secondary outcomes were largely derived from the core outcome set for trials on induction of labor. Based on a superiority hypothesis, it was calculated that a sample size of 126 would be required to detect a 4-hour reduction in the induction-to-delivery interval and a 1.5 point increase in the satisfaction score based on a 0 to 10 numerical rating scale with the level of significance set at 0.05, power at 80%, and a 10% drop out rate. Comparative analyses using an intention-to-treat approach were conducted using t tests, Mann-Whitney U tests, chi square tests, and Fisher exact tests as appropriate.

RESULTS

A total of 126 participants were randomized with 63 in each trial arm. The induction to birth interval was (mean ± standard deviation) 29.7±9.6 hours for those in the 3-hourly tugging group and 29.8±9.1 hours for those under standard care (P=.950), and maternal satisfaction with the induction of labor after 1 previous cesarean delivery birth process, assessed using a 0 to 10 numerical rating scale, was (median [interquartile range]) 8 [7–9] and 8 [7–9] (P=.936), respectively. The cesarean delivery rate was 37 of 63 (59%) vs 41 of 63 (65%) (P=.238) for those in the tugging group vs standard care, and the main indication for unplanned cesarean delivery was failure to progress with an incidence of 24 of 37 (65%) and 24 of 41 (59%) (P=.914) for tugging vs standard care arms, respectively. Three-hourly tugging also did not shorten the interval from induction to balloon displacement, amniotomy, the start of oxytocin infusion, or the second stage of labor.

CONCLUSION

Tugging the catheter every 3 hours during scheduled 12-hour Foley balloon placement for induction of labor after 1 previous cesarean delivery did not hasten birth or improve patient satisfaction when compared with standard care.