Induction of labor after one previous Cesarean section in women with an unfavorable cervix: A retrospective cohort study

Randomized controlled trial comparing efficacy of a combination regime containing two cervical sensitizers (mifepristone + Foley's catheter) versus single agent mifepristone or Foley's catheter for labor induction in women attempting TOLAC at late third trimester with a dead fetus in utero

Randomized controlled trial comparing efficacy of a combination regime containing two cervical sensitizers (mifepristone + Foley's catheter) versus single agent mifepristone or Foley's catheter for labor induction in women attempting TOLAC at late third trimester with a dead fetus in utero.

AIM

To compare efficacy and safety of a new combination regime comprising of two cervical sensitizers used simultaneously with single agents, for labor induction in women attempting TOLAC at ≥34 weeks' gestation with a dead fetus.

METHOD

This was a multiarm randomized controlled trial (RCT) where participants received one of the three regimes-single agent oral Mifepristone 200 mg, intracervical Foley's catheter (16 Fr size, filled with 40 mL normal saline after intracervical instillation), and combination regime consisting of both used simultaneously. Number of women undergoing vaginal birth within 48 h of induction (VB48 ) was the primary outcome compared between groups.

RESULTS

VB48 was higher in participants on combination regime in comparison to participants on Foley's catheter (54 vs. 42). Total vaginal births were higher in participants on combination regime compared to both single agents (58 vs. 48 and 44). Duration and dose of oxytocin augmentation was lower in participants on combination regime compared to both single agents. Induction birth interval was short in participants on combination regime compared to those on Foley's catheter. Maternal complications between groups were similar.

CONCLUSION

Combination of cervical sensitizers for labor induction in late third trimester among women with dead fetus attempting TOLAC resulted in higher proportion of vaginal births and might reduce risk of scar dehiscence due to requirement of a lower dose of oxytocin for augmentation.

Retrospective evaluation of labor induction with scar uterus at the university hospital of Rennes

OBJECTIVE

The aim of the study was a retrospective evaluation of labor induction in women with one previous cesarean section. The primary outcome was the mode of delivery. We also studied the severe maternal and neonatal morbidity and identify some prediction factors of vaginal delivery after labor induction after one previous cesarean section.

STUDY DESIGN

This was a retrospective observational monocentric study performed over the period from January 1st, 2016 to April 30th, 2020 at the university hospital of Rennes. Were included women with scar uterus because of one previous cesarean section with a viable singleton fetus in cephalic presentation and an induction of labor for medical reason, at term. Multivariate logistic regression analysis was used to analyze prediction of vaginal delivery after labor induction after one previous cesarean section. We also studied maternal (included uterine rupture, loss of blood, obstetrical injury of anus sphincter) and neonatal (APGAR score, arterial umbilical pH after 1 minute of life and eventual admission to neonatal unit) morbidity. We used a stepwise multivariate logistic regression model to select variables for multivariate analysis. The model with the lowest Akaike Index Criteria was chosen.

RESULTS

The study enrolled 353 women with scar uterus: 121 women were induced by balloon catheter, 57 by osmotic cervical dilatators, 91 by oxytocin alone, 84 by amniotomy. Vaginal delivery rate was 47,9%. There was 45% of vaginal delivery in the group with Bishop < 6 before induction of labor versus 62% in the group with Bishop ≥ 6. There was no statistically significative difference in neonatal and maternal severe morbidities between vaginal delivery and cesarean section: 4,5% of severe maternal morbidities (n = 16). Among their, we highlighted 7 uterine ruptures (3,8%). We observed also 3% of postpartum severe hemorrhage in vaginal delivery group (n = 5) against 1,6% in cesarian section group (n = 3) with no statistical significant difference (p = 0,632). Regarding to the obstetric perineal tears and lacerations we noticed 1,2% of OASIS 3 (n = 2) and 0,6% of OASIS 4 (n = 1). Severe neonatal morbidities were comparable by mode of delivery without significant difference: APGAR score at 5 min was similar (p = 1), as well as arterial umbilical pH after 1 min. (p = 0.719) and admissions to a neonatal unit (p = 1). Two variables were statistically associated with vaginal delivery after labor induction in women with scar uterus: Bishop score ≥ 6 (OR = 0,44; 95%CI: 0,25-0,81) and/or previous vaginal delivery after cesarean section (OR = 0,17; 95%CI: 0,08-0,35).

CONCLUSION

With 47,9% of vaginal delivery after labor induction in women with scar uterus, only 3.8% (n = 7/353) of uterine ruptures, less than 1% APGAR < 7 at 5 min (n = 3/353), induction on scar uterus should be consider in obstetrical practice. Bishop score ≥ 6 and/or previous vaginal delivery after cesarean section are associated to vaginal delivery after labor induction.

Comparison of Vaginal Birth Rate between Induction of Labour and Expectant Management at 40 Weeks in Women with a Previous Caesarean Section: A Pilot Randomized Controlled Trial

Background

The optimum time of labour induction among women with a previous caesarean without any pregnancy complication and eligible and willing for vaginal delivery is not specified. This study compares the vaginal birth rates between induction at 40 weeks and expectant management till 41 weeks.

Method

We conducted this parallel design nonblinded, randomized controlled trial in a tertiary care teaching institution in South India on women with a previous lower segment caesarean section eligible for a trial of labour with singleton foetus without any pregnancy complication at recruitment. We screened 1886 women. Sixty women underwent block (of 6 each) randomization into two groups of thirty each at 40 weeks. We induced the women in the intervention group at 40 weeks with oxytocin or a single 24-hour application of a Foley catheter followed by oxytocin infusion and amniotomy. The expectant group underwent maternal and foetal surveillance and induction at 41 weeks with the same protocol if not delivered by then. We compared the primary outcome of the proportion of vaginal birth rate with a chi-square test.

Result

Data from all sixty women were analyzed. Twenty (66.67%) in the induction compared to ten (33.33%) in the expectant group delivered vaginally. This difference was significant (RR 2.0, 95% CI: 1.13-3.52; P = 0.016). One woman in the expectant group had scar dehiscence.

Conclusion

Among women with a previous caesarean scar, labour induction at 40 weeks has a significantly higher vaginal birth rate than those managed expectantly till 41 weeks. More extensive trials are feasible and recommended. Trial Registry. The trial was prospectively registered with the clinical trial registry of India. This trial is registered with CTRI/2018/09/015719 (date of registration 14th September 2018).

Methods of induction of labor after cesarean with no prior vaginal delivery-Perinatal outcomes

OBJECTIVE

To study the association between the method of induction of labor (IOL) and perinatal outcomes, among women undergoing labor after cesarean (LAC) with no prior vaginal delivery.

METHOD

A retrospective study including all women with no prior vaginal delivery undergoing IOL for LAC between March 2011 and January 2021. Oxytocin administration following prelabor rupture of membranes (PROM), oxytocin administration only, extra-amniotic balloon, and amniotomy were compared.

RESULTS

Overall, 363 women met the inclusion criteria: extra-amniotic balloon (157, 43.3%), oxytocin following PROM (95, 26.2%), amniotomy (72, 19.8%), and oxytocin (39, 10.7%). LAC success rate did not differ among study groups (P = 0.114), varying between 62.1% and 79.5%. There were three uterine ruptures (0.8%) in the entire cohort. The rate of uterine rupture, postpartum hemorrhage, and the composite of both were similar in all study groups. Neonatal outcomes did not differ between study groups, with composite adverse neonatal outcomes varying between 7.4% in the oxytocin following PROM to 1.9% in the extra-amniotic balloon group (P = 0.141). The following factors were independently associated with LAC success: taller maternal height, lower body mass index, earlier gestational age, and epidural analgesia.

CONCLUSIONS

All examined IOL methods with an unfavorable cervix carried similar outcomes. The clinical practice should be individualized.

Mechanical Methods for the Induction of Labour After Previous Caesarean Section – An Updated, Evidence-based Review

There are currently no up-to-date evidence-based recommendations on the preferred method to induce labour after previous Caesarean section, especially for patients with unripe cervix, as randomised controlled studies are lacking. Intravenous oxytocin and misoprostol are contraindicated in these women because of the high risk of uterine rupture. In women with ripe cervix (Bishop Score > 6), intravenous administration of oxytocin is an effective procedure with comparable rates of uterine rupture to those with spontaneous onset of labour. Vaginal prostaglandin E ₂ (PGE ₂ ) and mechanical methods (balloon catheters, hygroscopic cervical dilators) are effective methods to induce labour in pregnant women with unripe cervix and previous Caesarean section. According to current guidelines, the administration of PGE ₂ is associated with a higher rate of uterine rupture compared to balloon catheters. Balloon catheters are therefore a suitable alternative to PGE ₂ to induce labour after previous Caesarean section, even though this is an off-label use. In addition to two meta-analyses published in 2016, 12 mostly retrospective cohort/observational studies with low to moderate levels of evidence have been published on mechanical methods of cervical ripening after previous Caesarean section. But because of the significant heterogeneity of the studies, substantial differences in study design, and insufficient numbers of pregnant women included in the studies, it is not possible to make any evidence-based recommendations based on these studies. According to a recent meta-analysis, the average rate using balloon catheters is approximately 53% and the average rate after spontaneous onset of labour is 72%. The uterine rupture rate was 0.2–0.9% for vaginal PGE ₂ and 0.56–0.94% for balloon catheters and is therefore comparable to the uterine rupture rate associated with spontaneous onset of labour. According to the product informations, hygroscopic cervical dilators (Dilapan-S) are currently the only method which is not contraindicated for cervical ripening/induction of labour in women with previous Caesarean section, although data are insufficient. Well-designed, randomised, controlled studies with sufficient case numbers comparing balloon catheters and hygroscopic cervical dilators with mechanical methods and vaginal prostaglandin E ₂ /oral misoprostol are therefore necessary to allow proper decision-making.

Time matters-a Swedish cohort study of labor duration and risk of uterine rupture

INTRODUCTION

Uterine rupture is an obstetric emergency associated with maternal and neonatal morbidity. The main risk factor is a prior cesarean section, with rupture occurring in subsequent labor. The aim of this study was to assess the risk of uterine rupture by labor duration and labor management.

MATERIAL AND METHODS

This is a Swedish register-based cohort study of women who underwent labor in 2013-2018 after a primary cesarean section (n = 20 046). Duration of labor was the main exposure, calculated from onset of regular labor contractions and birth; both timepoints were retrieved from electronic medical records for 12 583 labors, 63% of the study population. Uterine rupture was calculated as events per 1000 births at different timepoints during labor. Risk estimates for uterine rupture by labor duration, induction of labor, use of oxytocin and epidural analgesia were calculated using Poisson regression, adjusted for maternal and birth characteristics. Estimates were presented as adjusted rate ratios (ARR) with 95% confidence intervals (CI).

RESULTS

The prevalence of uterine rupture was 1.4% (282/20 046 deliveries). Labor duration was 9.88 hours (95% CI 8.93-10.83) for women with uterine rupture, 8.20 hours (95% CI 8.10-8.31) for women with vaginal delivery, and 10.71 hours (95% CI 10.46-10.97) for women with cesarean section without uterine rupture. Few women (1.0/1000) experienced uterine rupture during the first 3 hours of labor. Uterine rupture occurred in 15.6/1000 births with labor duration over 12 hours. The highest risk for uterine rupture per hour compared with vaginal delivery was observed at 6 hours (ARR 1.20, 95% CI 1.11-1.30). Induction of labor was associated with uterine rupture (ARR 1.54, 95% CI 1.19-1.99), with a particular high risk seen in those induced with prostaglandins and no risk observed with cervical catheter (ARR 1.19, 95% CI 0.83-1.71). Labor augmentation with oxytocin (ARR 1.60, 95% CI 1.25-2.05) and epidural analgesia (ARR 1.63, 95% CI 1.27-2.10) were also associated with uterine rupture.

CONCLUSIONS

Labor duration is an independent factor for uterine rupture among women attempting vaginal delivery after cesarean section. Medical induction and augmentation of labor increase the risk, regardless of maternal and birth characteristics.

Delivery after fetal death in women with earlier cesarean section. A review

The clinical management of intrauterine fetal demise (IUFD) in women with a previous cesarean delivery presents a dilemma for the obstetrician. With the current reluctance of obstetricians to perform vaginal birth after cesarean (VBAC) and the paucity of data to counsel women regarding maternal risks, management options are limited by physician's clinical experience and biases. In the setting of fetal demise, maternal safety becomes the primary concern. Medicolegal pressures may prevent physicians from attempting a trial of labor in this situation. In this review we will a focus on frequency of birth with IUFD after cesarean section (CS), we discuss the options (VBAC vs CS), different complications, methods for induction of vaginal birth as well as risk factors of vaginal birth and cesarean delivery.

Morbidity associated with the use of Foley balloon for cervical ripening in women with prior cesarean delivery

OBJECTIVE

We evaluated the morbidity of Foley balloon for cervical ripening in comparison to oxytocin alone in women with a prior cesarean delivery.

STUDY DESIGN

A four-hospital retrospective review of all women with viable singleton pregnancies and history of a single prior cesarean delivery presenting for cervical ripening between 1994 and 2015. Exposure groups were either Foley balloon or oxytocin, at the treating physician's discretion. The primary outcome was defined as maternal morbidity, evaluated by a composite that included hemorrhage, and/or uterine infection, and/or uterine rupture. We defined two secondary outcomes: neonatal morbidity, and vaginal delivery rate. Neonatal morbidity was evaluated by a composite that included five-minute APGAR score <7 and/or NICU admission. We adjusted results for potential confounding variables, including hospital site, maternal age and race, initial cervical dilation, and gestational age at delivery.

RESULTS

We identified 688 patients who received ripening, 276 by Foley balloon and 412 by oxytocin. There was no significant difference in the primary outcome of maternal morbidity between groups: 38 (13.8%) in the Foley balloon group and 79 (19.2%) in the oxytocin group (aOR 1.43; 95% CI, 0.90-2.27). There was no significant difference in the secondary outcome of neonatal morbidity: 31 (11.3%) in the Foley balloon group and 51 (12.4%) in the oxytocin group (aOR 1.02; 95% CI, 0.57-1.80). The rate of vaginal delivery was significantly less in the Foley balloon group compared to the oxytocin group: 56.2% vs 64.1%, p = .037.

CONCLUSION

When cervical ripening with either Foley balloon or oxytocin was utilized at the physician's discretion in women with prior cesarean, there was no identified difference in maternal and neonatal morbidity, but the rate of successful vaginal delivery was lower.

Mifepristone pretreatment followed by misoprostol 200 mcg buccal for the medical management of intrauterine fetal death at 14-28 weeks: A randomized, placebo-controlled, double blind trial

OBJECTIVE

To evaluate whether fetal and placental expulsion is more likely within 48 h if women receive mifepristone pre-treatment vs placebo pre-treatment followed by misoprostol 200 mcg buccally for treatment of fetal death at 14 weeks 0 days to 28 weeks and 6 days gestation.

STUDY DESIGN

We randomized 176 women with a confirmed fetal death between 14 weeks and 0 days to 28 weeks and 6 days to mifepristone 200 mg or placebo; 24 h later all participants received misoprostol 200 mcg buccally every 3 h for up to 16 doses or 48 h. The trial took place in Hanoi, Vietnam and Mexico City in 2015-2018.

RESULTS

Complete expulsion of the fetus and placenta within 48 h of misoprostol administration occurred in 74 of 90 women (82.2%, 95% confidence interval (CI), 72.7%-89.5%) in the mifepristone-misoprostol group and in 70 of 86 women (81.4%, 95% CI, 71.6%-89.0%) in the placebo-misoprostol group (Relative Risk (RR) 1.01, 95%CI 0.87-1.16, p = 0.887). The median time from the start of the misoprostol induction to fetal expulsion was shorter among women who received mifepristone-misoprostol compared to women assigned to placebo-misoprostol (7 h vs ±5 vs 12 ± 13 h; p < 0.001). Women in the mifepristone-misoprostol group were more likely to expel the fetus within 24 h of the start of misoprostol administration (96% vs 78%; RR 1.22 (1.09-1.39) p = 0.009).

CONCLUSION(S)

Mifepristone-misoprostol did not result in a higher rate of complete expulsion of the fetus and the placenta within 48 h of the start of misoprostol administration without any additional surgical intervention or medication (e.g. additional misoprostol doses or oxytocin) than placebo-misoprostol. However, treatment with mifepristone-misoprostol did result in a shorter time to expulsion than placebo misoprostol.

IMPLICATIONS

Pretreatment with mifepristone followed by misoprostol bucally resulted in a shorter treatment time for medical management of fetal death than treatment with misoprostol alone. Pre-treatment with mifepristone may be more acceptable to women and providers by both reducing the length of hospital stay and the amount of misoprostol required.