Early versus delayed amniotomy with immediate oxytocin after Foley catheter cervical ripening in nulliparous labor induction: A randomized trial

Abstract

Objective: To evaluate immediate oxytocin and early amniotomy compared with delayed amniotomy after Foley catheter cervical ripening in nulliparous women on intervention-to-delivery interval.Methods: A randomized trial was conducted from September 2020 to March 2021.A total of 140 term nulliparas (70 early amniotomy, 70 delayed amniotomy) with Foley catheter-ripened cervices (dilatation ≥3 cm achieved), singleton fetus, cephalic presentation with intact membranes, and reassuring fetal heart rate tracing were recruited. Women were randomized to immediate titrated intravenous oxytocin infusion and early amniotomy or delayed amniotomy (after 4 h of oxytocin). The primary outcome was intervention (oxytocin)-to-delivery interval (h).Results: Intervention-to-delivery intervals (h) were mean ± standard deviation 9.0 ± 3.6 versus 10.6 ± 3.5 h (mean difference of 1.4 h) (P = 0.004) for the early versus delayed amniotomy arms, respectively. Birth rates at 6 h after oxytocin infusion were 19 of 70 (27.1%) versus 8 of 70 (11.4%) (relative risk, 2.38 [95% confidence interval (CI), 1.11-5.06]; number needed to treat: 7 [95% CI, 3.5-34.4]) (P = 0.03), cesarean delivery rates were 29 of 70 (41.4%) versus 33 of 70 (47.1%) (relative risk, 0.88; 95% CI, 0.61-1.28) (P = 0.50), and maternal satisfaction on birth process were a median of 7 (interquartile range, 7-8) versus 7 (interquartile range, 7-8) (P = 0.40) for the early versus delayed amniotomy arms, respectively. Conclusion:In term nulliparas with cervices ripened by Foley catheter, immediate oxytocin and early amniotomy compared with a planned 4-h delay to amniotomy shortened the intervention-to-delivery interval but did not significantly reduce the cesarean delivery rate.

Two different regimens of outpatient Foley catheter induction of labor in nulliparas: A randomized trial

“…This result supported our hypothesis that prolonging the interval between expulsion of balloon to further active steps of amniotomy and titrated oxytocin infusion with an expectant hospital return policy did not adversely impact the dynamics associated driving active phase of labor and on the second stage of labor. Our data on amniotomy to delivery interval duration were comparable to previous studies that involved nulliparous women and Foley catheter cervical ripening 21,22 …”

“…Our data on amniotomy to delivery interval duration were comparable to previous studies that involved nulliparous women and Foley catheter cervical ripening. 21,22 The cesarean delivery rates were identical across trial arms which was probably coincidental but nevertheless a strong indicator that the trial interventions om timing of hospital return after Foley expulsion at home would not materially affect this outcome metric. Our 48.5% cesarean delivery rate is relatively high.…”

Predictors of maternal satisfaction with labor induction: A prospective observational cohort study

“…In our labor induction protocol, amniotomy is routinely performed immediately after successful cervical ripening especially when Foley balloon is used. 29,30 Women who did not have amniotomy at labor induction in our study were disproportionately delivered by unplanned cesarean for failed induction or for abnormal fetal heart tracing with the cervix still unfavorable. Hence, amniotomy is probably a surrogate measure of a ripened cervix, an interim measure of success during labor induction, and this intervention could predict maternal satisfaction as we have found.…”

“…Amniotomy in labor was independently predictive of maternal satisfaction. In our labor induction protocol, amniotomy is routinely performed immediately after successful cervical ripening especially when Foley balloon is used 29,30 . Women who did not have amniotomy at labor induction in our study were disproportionately delivered by unplanned cesarean for failed induction or for abnormal fetal heart tracing with the cervix still unfavorable.…”