Which is the safer method of labor induction for oligohydramnios women? Transcervical double balloon catheter or dinoprostone vaginal insert

[Prostaglandins or cervical balloon for the induction of labor for cervical ripening: A literature review]

OBJECTIVE

Induction of labor in France concerns one birth out of four with 70% of induction starting by cervical ripening, either with a pharmacological (prostaglandins) or a mechanical (balloon) method. This review aims to compare these two methods within current knowledge, using the PRISMA methodology.

METHODS

Trials comparing these two methods, published or unpublished up to July 2023, in French or English were searched for in the PubMed, Cochrane Library and ClinicalTrial.govs datasets. Fifty articles including 10,689 women were selected. The outcomes of interest were those from the Core Outcome Set for trails on Induction of Labour (COSIOL) list: mode of delivery, time from induction-to-birth, maternal and neonatal morbidity, and maternal satisfaction.

RESULT

No differences were observed between the two methods for the mode of delivery or neonatal and maternal morbidity. The time from induction-to-birth was longer for mechanical methods. Those were also associated with a greater need for oxytocin, less uterine hyperstimulation and less instrumental deliveries. Maternal satisfaction was assessed in only nine trials using various scales which made the interpretation of maternal satisfaction.

CONCLUSION

The efficacy of these two induction methods is similar for vaginal delivery, but it remains to be seen which one best meets women's satisfaction criteria.

Outpatient cervical ripening with balloon catheters: A Bayesian network meta-analysis of randomized controlled trials

BACKGROUND

One in four labors are induced. The process of cervical ripening can be lengthy and pre-labor hospitalization is required. Outpatient cervical ripening can be an attractive alternative.

OBJECTIVES

To evaluate the efficacy and safety of outpatient cervical ripening with a balloon catheter compared with inpatient balloon catheter or prostaglandin E2 (PGE2 ).

SEARCH STRATEGY

The PubMed, MEDLINE, Embase, ClinicalTrials.gov, and Cochrane Library databases were searched from their inception to October 15, 2022.

SELECTION CRITERIA

Randomized controlled trials comparing the outpatient balloon catheter with inpatient balloon catheter or inpatient PGE2 for term cervical ripening.

DATA COLLECTION AND ANALYSIS

Bayesian network meta-analysis was performed. The primary outcome was the cesarean delivery rate. The secondary outcomes included instrumental delivery, the time from intervention-to-birth, oxytocin augmentation, total hospital duration, and maternal/neonatal adverse events.

MAIN RESULTS

Twenty-nine randomized controlled trials with a total of 6004 participants were identified. No difference in the cesarean delivery rate was revealed among the three interventions. Compared with inpatient balloon catheter, outpatient balloon catheter had shorter total hospital duration (mean difference -8.58, 95% confidence interval -17.02 to -1.10). No differences were revealed in the time from intervention-to-birth, instrumental delivery, postpartum hemorrhage, 5-min Apgar score less than 7, umbilical cord arterial pH less than 7.1, and neonatal intensive care unit admission among the three interventions.

CONCLUSIONS

Outpatient balloon catheter in low-risk term pregnancies is an available option that could be considered for cervical ripening. The safety and effectiveness are comparable to inpatient cervical ripening methods.

Application of intrauterine balloons in cervical ripening

INTRODUCTION

At present, the double balloon represented by the COOK Cervix Ripening Balloon and the single balloon represented by the Foley catheter are the commonly used intrauterine balloons. The application of intrauterine balloons in cervical ripening has evolved over 100 years. Although intrauterine balloons have been widely used in cervical ripening, the effect of labor induction in clinical practice does not satisfy all clinicians, especially patients with poor cervical maturity.

AREAS COVERED

The research in this review is about intrauterine balloons and cervical ripening.

EXPERT OPINION

This article reviews the historical evolution and different application methods of intrauterine balloons in cervical ripening, such as application range, placement method and placement duration of intrauterine balloons, volume and temperature of the solution fillings, and whether to apply traction to the catheter. We aim to better understand the principle of intrauterine balloons in cervical ripening and make this method more effective.

Using dinoprostone slow release vaginal insert for cervical ripening in term-pregnancy with oligohydramnios

AIMS

The study purposed to evaluate the success rate of cervical ripening using dinoprostone controlled-release vaginal insert and reveal some factors relating to successful cervical ripening.

METHODS

This cross-sectional study was conducted at Tu Du Hospital in Vietnam from December 2021 to August 2022. The study enrolled 200 pregnant women with gestational age ≥37 weeks diagnosed with oligohydramnios. These candidates underwent dinoprostone cervical ripening (DCR) according to the local protocol. The Bishop score ≥7 after 24 h was determined for the successful cervical ripening (SCR).

RESULTS

In total, the success rate of DCR achieved at 57.5% and the cesarean delivery rate was 46.5%. None of the severe side-effects and complications was present. Using multivariable logistic regression, the study found that the body mass index ≥25 kg/m² and oxytocin infusion drip related to SCR with adjusted odds ratio (aOR): 3.67 (95% confidence intervals [CI]: 1.78-7.57) and aOR: 4.68 (95% CI: 1.84-11.93), p < 0.001. Using the Kaplan-Meier curve, the present study revealed a significant difference between Bishop <3 and ≥3 following the duration time of cervical ripening, with hazard ratio: 1.38 (95% CI: 1.19-1.59), p < 0.001. The time duration of cervical ripening was not significantly different following amniotic fluid index from 3 to 5 cm.

CONCLUSIONS

Cervical ripening using a dinoprostone vaginal insert is a potentially acceptable method in term pregnancy accompanying with oligohydramnios. The probability of SCR can be predicted on a careful assessment of relative factors by obstetricians. Further studies are required to strengthen these findings.

Delivery Mode among Patients with Oligohydramnios with or without Fetal Growth Restriction by Induction Method

OBJECTIVE

This study aimed to evaluate the association of induction method on delivery mode in pregnancies complicated by oligohydramnios with and without fetal growth restriction (FGR).

STUDY DESIGN

This was a secondary analysis of a National Institutes of Health funded retrospective cohort study of singleton deliveries at a tertiary-care hospital between 2002 and 2013 with diabetes, mild hypertension, and/or FGR. Chart abstraction was performed by trained research nurses. Patients with a diagnosis of fetal oligohydramnios with and without FGR were identified. Our analytic cohort was further stratified into three groups per initial induction agent: prostaglandins (PGEs) alone, PGE plus mechanical ripening, or oxytocin only. Primary outcome was mode of delivery. Secondary outcomes included indications for cesarean delivery and neonatal morbidity.

RESULTS

Out of 4,929 patients in the original database, 546 subjects with fetal oligohydramnios were identified; of these, 270 were induced and included for analysis. Outcomes were compared between 171 patients who had fetuses with isolated oligohydramnios and 99 patients who had fetuses with oligohydramnios and FGR. There were no significant differences in demographic characteristics between the groups. Patients with fetuses with isolated oligohydramnios had similar rates of spontaneous vaginal delivery (SVD) when PGEs were used (n = 44/79, 55.7% PGE alone, n = 44/76, 57.9% PGE with mechanical ripening) and when they were not used (n = 5/13, 38.5% oxytocin alone; p = 0.43). Similarly, the majority of patients in both cohorts underwent SVD regardless of induction method (n = 30/44, 68.2% PGE alone, n = 30/44, 68.2% PGE with mechanical ripening, and n = 6/10, 60% oxytocin alone; p = 0.90). There was no significant difference in composite neonatal morbidity.

CONCLUSION

In patients with fetuses with oligohydramnios with and without FGR, most patients delivered by SVD regardless of induction method. In this population, PGE use was associated with a high chance of SVD in patients with fetuses with suspected placental insufficiency regardless of the presence of absence of FGR.

KEY POINTS

· The majority of fetuses with oligohydramnios with or without FGR deliver vaginally.. · The use of prostaglandins did not increase rates of cesarean for fetal distress in oligohydramnios.. · Prostaglandin use did not increase rate of neonatal intensive care unit admission among pregnancies with oligohydramnios..

Mechanical methods for induction of labour

BACKGROUND

Mechanical methods were the first methods developed to ripen the cervix and induce labour. During recent decades they have been substituted by pharmacological methods. Potential advantages of mechanical methods, compared with pharmacological methods may include reduction in side effects that could improve neonatal outcomes. This is an update of a review first published in 2001, last updated in 2012.

OBJECTIVES

To determine the effectiveness and safety of mechanical methods for third trimester (> 24 weeks' gestation) induction of labour in comparison with prostaglandin E2 (PGE2) (vaginal and intracervical), low-dose misoprostol (oral and vaginal), amniotomy or oxytocin.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP), and reference lists of retrieved studies (9 January 2018). We updated the search in March 2019 and added the search results to the awaiting classification section of the review.

SELECTION CRITERIA

Clinical trials comparing mechanical methods used for third trimester cervical ripening or labour induction with pharmacological methods. Mechanical methods include: (1) the introduction of a catheter through the cervix into the extra-amniotic space with balloon insufflation; (2) introduction of laminaria tents, or their synthetic equivalent (Dilapan), into the cervical canal; (3) use of a catheter to inject fluid into the extra-amniotic space (EASI). This review includes the following comparisons: (1) specific mechanical methods (balloon catheter, laminaria tents or EASI) compared with prostaglandins (different types, different routes) or with oxytocin; (2) single balloon compared to a double balloon; (3) addition of prostaglandins or oxytocin to mechanical methods compared with prostaglandins or oxytocin alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed risk of bias. Two review authors independently extracted data and assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

This review includes a total of 112 trials, with 104 studies contributing data (22,055 women; 21 comparisons). Risk of bias of trials varied. Overall, the evidence was graded from very-low to moderate quality. All evidence was downgraded for lack of blinding and, for many comparisons, the effect estimates were too imprecise to make a valid judgement.   Balloon versus vaginal PGE2: there may be little or no difference in vaginal deliveries not achieved within 24 hours (risk ratio (RR) 1.01, 95% confidence interval (CI) 0.82 to 1.26; 7 studies; 1685 women; low-quality evidence) and there probably is little or no difference in caesarean sections (RR 1.00, 95% CI 0.92 to 1.09; 28 studies; 6619 women; moderate-quality evidence) between induction of labour with a balloon catheter and vaginal PGE2. A balloon catheter probably reduces the risk of uterine hyperstimulation with fetal heart rate (FHR) changes (RR 0.35, 95% CI 0.18 to 0.67; 6 studies; 1966 women; moderate-quality evidence), serious neonatal morbidity or perinatal death (RR 0.48, 95% CI 0.25 to 0.93; 8 studies; 2757 women; moderate-quality evidence) and may slightly reduce the risk of aneonatal intensive care unit (NICU) admission (RR 0.82, 95% CI 0.65 to 1.04; 3647 women; 12 studies; low-quality evidence). It is uncertain whether there is a difference in serious maternal morbidity or death (RR 0.20, 95% CI 0.01 to 4.12; 4 studies; 1481 women) or five-minute Apgar score < 7 (RR 0.74, 95% CI 0.49 to 1.14; 4271 women; 14 studies) because the quality of the evidence was found to be very low and low, respectively. Balloon versus low-dose vaginal misoprostol: it is uncertain whether there is a difference in vaginal deliveries not achieved within 24 hours between induction of labour with a balloon catheter and vaginal misoprostol (RR 1.09, 95% CI 0.85 to 1.39; 340 women; 2 studies; low-quality evidence). A balloon catheter probably reduces the risk of uterine hyperstimulation with FHR changes (RR 0.39, 95% CI 0.18 to 0.85; 1322 women; 8 studies; moderate-quality evidence) but may increase the risk of a caesarean section (RR 1.28, 95% CI 1.02 to 1.60; 1756 women; 12 studies; low-quality evidence). It is uncertain whether there is a difference in serious neonatal morbidity or perinatal death (RR 0.58, 95% CI 0.12 to 2.66; 381 women; 3 studies), serious maternal morbidity or death (no events; 4 studies, 464 women), both very low-quality evidence, and five-minute Apgar score < 7 (RR 1.00, 95% CI 0.50 to 1.97; 941 women; 7 studies) and NICU admissions (RR 1.00, 95% CI 0.61 to 1.63; 1302 women; 9 studies) both low-quality evidence. Balloon versus low-dose oral misoprostol: a balloon catheter probably increases the risk of a vaginal delivery not achieved within 24 hours (RR 1.28, 95% CI 1.13 to 1.46; 782 women, 2 studies, and probably slightly increases the risk of a caesarean section (RR 1.17, 95% CI 1.04 to 1.32; 3178 women; 7 studies; both moderate-quality evidence) when compared to oral misoprostol. It is uncertain whether there is a difference in uterine hyperstimulation with FHR changes (RR 0.81, 95% CI 0.48 to 1.38; 2033 women; 2 studies), serious neonatal morbidity or perinatal death (RR 1.11, 95% CI 0.60 to 2.06; 2627 women; 3 studies), both low-quality evidence, serious maternal morbidity or death (RR 0.50, 95% CI 0.05 to 5.52; 2627 women; 3 studies), very low-quality evidence, five-minute Apgar scores < 7 (RR 0.71, 95% CI 0.38 to 1.32; 2693 women; 4 studies) and NICU admissions (RR 0.82, 95% CI 0.58 to 1.17; 2873 women; 5 studies) both low-quality evidence.

AUTHORS' CONCLUSIONS

Low- to moderate-quality evidence shows mechanical induction with a balloon is probably as effective as induction of labour with vaginal PGE2. However, a balloon seems to have a more favourable safety profile. More research on this comparison does not seem warranted. Moderate-quality evidence shows a balloon catheter may be slightly less effective as oral misoprostol, but it remains unclear if there is a difference in safety outcomes for the neonate. When compared to low-dose vaginal misoprostol, low-quality evidence shows a balloon may be less effective, but probably has a better safety profile. Future research could be focused more on safety aspects for the neonate and maternal satisfaction.

Comparing the effectiveness and safety of Dinoprostone vaginal insert and double-balloon catheter as cervical ripening treatments in Chinese patients

Background

This retrospective study was to compare the effectiveness and safety of Dinoprostone vaginal insert vs. double-balloon catheter as cervical ripening agents for labor induction.

Methods

Pregnant women with Bishop score <7, who received either Dinoprostone vaginal insert 10 mg or Cook's double-balloon catheter for labor induction, were studied. The primary outcome was the rate of vaginal delivery within 48 h; the secondary outcomes were the proportion of women undergoing cesarean section, labor duration, oxytocin administration, changes in Bishop score, complications during labor, and maternal/neonatal outcomes.

Results

One hundred and eighty-two women were included in Dinoprostone group, and 199 women were in double-balloon catheter group. The rate of vaginal delivery within 48 h was significantly higher in Dinoprostone group than that in double-balloon catheter group (90.11% vs. 75.38%, P = 0.0002). There were 18 cesarean section deliveries (9.89%) in Dinoprostone group and 49 cesarean section deliveries (24.62%) in double-balloon catheter group, with significant differences between two groups (P = 0.0002). The duration of labor was higher in Dinoprostone group, while the augmentation with oxytocin was significantly lower in Dinoprostone group than in double-balloon catheter group (all P < 0.0001). The incidence of chorioamnionitis was significantly higher in double-balloon catheter group as compared with Dinoprostone group (0 vs. 12, P = 0.0005), while neonatal outcomes were similar in two groups.

Conclusion

Dinoprostone vaginal insert as cervical ripening agent is more effective for labor induction and with lower risks of chorioamnionitis as compared with double balloon catheter in Chinese populations.

Safety and efficacy of double-balloon catheter for cervical ripening: a Bayesian network meta-analysis of randomized controlled trials

BACKGROUND

Various methods are used for cervical ripening during the induction of labor. Mechanical and pharmacological methods are commonly used for cervical ripening. A double-balloon catheter was specifically developed to ripen the cervix and induce labor; however, the efficacy of the double-balloon catheter in cervical ripening compared to other methods is unknown.

METHODS

We searched five databases and performed a Bayesian network meta-analysis. Six interventions (double-balloon catheter, Foley catheter, oral misoprostol, vaginal misoprostol, dinoprostone, and double-balloon catheter combined with oral misoprostol) were included in the search. The primary outcomes were cesarean delivery rate and time from intervention-to-birth. The secondary outcomes were as follows: Bishop score increment; achieving a vaginal delivery within 24 h; uterine hyperstimulation with fetal heart rate changes; need for oxytocin augmentation; instrumental delivery; meconium staining; chorioamnionitis; postpartum hemorrhage; low Apgar score; neonatal intensive care unit admission; and arterial pH.

RESULTS

Forty-eight randomized controlled trials involving 11,482 pregnant women were identified. The cesarean delivery rates of the cervical ripening with a double-balloon catheter and oral misoprostol, oral misoprostol, and vaginal misoprostol were significantly lower than cervical ripening with a Foley catheter (OR = 0.48, 95% CI: 0.23-0.96; OR = 0.74, 95% CI: 0.58-0.93; and OR = 0.79, 95% CI: 0.64-0.97, respectively; all P < 0.05). The time from intervention-to-birth of vaginal misoprostol was significantly shorter than the other five cervical ripening methods. Vaginal misoprostol and oral misoprostol increased the risk of uterine hyperstimulation with fetal heart rate changes compared to a Foley catheter. A double-balloon catheter with or without oral misoprostol had similar outcomes, including uterine hyperstimulation with fetal heart rate changes compared to a Foley catheter.

CONCLUSION

Double-balloon catheter did not show superiority when compared with other single method in primary and secondary outcomes of labor induction. The combination of double-balloon catheter with oral misoprostol was significantly reduced the rate of cesarean section compared to Foley catheter without increased risk of uterine hyperstimulation with fetal heart rate changes, which was shown in oral or vaginal misoprostol.

Comparison of the effectiveness and pregnancy outcomes of labor induction with dinoprostone or single-balloon catheter in term nulliparous women with borderline oligohydramnios

Backgrounds:

At present, there is no consensus on the induction methods in term pregnancy with borderline oligohydramnios. This study aimed to compare the effectiveness and pregnancy outcomes of labor induction with dinoprostone or single-balloon catheter (SBC) in term nulliparous women with borderline oligohydramnios.

Methods:

We conducted a retrospective cohort study from January 2016 to November 2018. During the study period, a total of 244 cases were enrolled. Of these, 103 cases were selected for induction using dinoprostone and 141 cases were selected for induction with SBC. The pregnancy outcomes between the two groups were compared. Primary outcomes were successful vaginal delivery rates. Secondary outcomes were maternal and neonatal adverse events. Multivariate logistic regression was used to assess the risk factors for vaginal delivery failure in the two groups.

Results:

The successful vaginal delivery rates were similar between the dinoprostone group and the SBC group (64.1% [66/103] vs. 59.6% [84/141], P = 0.475), even after adjustment for potential confounding factors (adjusted odds ratio [aOR]: 1.07, 95% confidence interval [CI]: 0.57–2.00, P = 0.835). The incidence of intra-amniotic infection was lower in the dinoprostone group than in the SBC group (1.9% [2/103] vs. 7.8% [11/141], P < 0.001), but the presence of non-reassuring fetal heart rate was higher in the dinoprostone group than in the SBC group (12.6% [13/103] vs. 0.7% [1/141], P < 0.001). Multivariate logistic regression showed that nuchal cord was a risk factor for vaginal delivery failure after induction with dinoprostone (aOR: 6.71, 95% CI: 1.96–22.95). There were three factors related to vaginal delivery failure after induction with SBC, namely gestational age (aOR: 1.51, 95% CI: 1.07–2.14), body mass index (BMI) >30 kg/m² (aOR: 2.98, 95% CI: 1.10–8.02), and fetal weight >3500 g (aOR: 2.49, 95% CI: 1.12–5.50).

Conclusions:

Term nulliparous women with borderline oligohydramnios have similar successful vaginal delivery rates after induction with dinoprostone or SBC, with their advantages and disadvantages. In women with nuchal cord, the risk of vaginal delivery failure is increased if dinoprostone is used in the induction of labor. BMI >30 kg/m², large gestational age, and estimated fetal weight >3500 g are risk factors for vaginal delivery failure after induction with SBC.

Mechanical methods for induction of labour

BACKGROUND

Mechanical methods were the first methods developed to ripen the cervix and induce labour. During recent decades they have been substituted by pharmacological methods. Potential advantages of mechanical methods, compared with pharmacological methods may include reduction in side effects that could improve neonatal outcomes. This is an update of a review first published in 2001, last updated in 2012.

OBJECTIVES

To determine the effectiveness and safety of mechanical methods for third trimester (> 24 weeks' gestation) induction of labour in comparison with prostaglandin E2 (PGE2) (vaginal and intracervical), low-dose misoprostol (oral and vaginal), amniotomy or oxytocin.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP), and reference lists of retrieved studies (9 January 2018). We updated the search in March 2019 and added the search results to the awaiting classification section of the review.

SELECTION CRITERIA

Clinical trials comparing mechanical methods used for third trimester cervical ripening or labour induction with pharmacological methods.Mechanical methods include: (1) the introduction of a catheter through the cervix into the extra-amniotic space with balloon insufflation; (2) introduction of laminaria tents, or their synthetic equivalent (Dilapan), into the cervical canal; (3) use of a catheter to inject fluid into the extra-amniotic space (EASI).This review includes the following comparisons: (1) specific mechanical methods (balloon catheter, laminaria tents or EASI) compared with prostaglandins (different types, different routes) or with oxytocin; (2) single balloon compared to a double balloon; (3) addition of prostaglandins or oxytocin to mechanical methods compared with prostaglandins or oxytocin alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed risk of bias. Two review authors independently extracted data and assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

This review update includes a total of 113 trials (22,373 women) contributing data to 21 comparisons. Risk of bias of trials varied. Overall, the evidence was graded from very-low to moderate quality. All evidence was downgraded for lack of blinding and, for many comparisons, the effect estimates were too imprecise to make a valid judgement.Balloon versus vaginal PGE2: there may be little or no difference in vaginal deliveries not achieved within 24 hours (average risk ratio (RR) 1.01, 95% confidence interval (CI) 0.82 to 1.26; 7 studies; 1685 women; I² = 79%; low-quality evidence) and there probably is little or no difference in caesarean sections (RR 1.00, 95% CI 0.92 to 1.09; 28 studies; 6619 women; moderate-quality evidence) between induction of labour with a balloon catheter and vaginal PGE2. A balloon catheter probably reduces the risk of uterine hyperstimulation with fetal heart rate (FHR) changes (RR 0.35, 95% CI 0.18 to 0.67; 6 studies; 1966 women; moderate-quality evidence), serious neonatal morbidity or perinatal death (RR 0.48, 95% CI 0.25 to 0.93; 8 studies; 2757 women; moderate-quality evidence) and may slightly reduce the risk of aneonatal intensive care unit (NICU) admission (RR 0.82, 95% CI 0.65 to 1.04; 3647 women; 12 studies; low-quality evidence). It is uncertain whether there is a difference in serious maternal morbidity or death (RR 0.20, 95% CI 0.01 to 4.12; 4 studies; 1481 women) or five-minute Apgar score < 7 (RR 0.74, 95% CI 0.49 to 1.14; 4271 women; 14 studies) because the quality of the evidence was found to be very low and low, respectively.Balloon versus low-dose vaginal misoprostol: it is uncertain whether there is a difference in vaginal deliveries not achieved within 24 hours between induction of labour with a balloon catheter and vaginal misoprostol (RR 1.09, 95% CI 0.85 to 1.39; 340 women; 2 studies; low-quality evidence). A balloon catheter probably reduces the risk of uterine hyperstimulation with FHR changes (RR 0.39, 95% CI 0.18 to 0.85; 1322 women; 8 studies; moderate-quality evidence) but may increase the risk of a caesarean section (average RR 1.28, 95% CI 1.02 to 1.60; 1756 women; 12 studies; I² = 45%; low-quality evidence). It is uncertain whether there is a difference in serious neonatal morbidity or perinatal death (RR 0.58, 95% CI 0.12 to 2.66; 381 women; 3 studies), serious maternal morbidity or death (no events; 4 studies, 464 women), both very low-quality evidence, and five-minute Apgar score < 7 (RR 1.00, 95% CI 0.50 to 1.97; 941 women; 7 studies) and NICU admissions (RR 1.00, 95% CI 0.61 to 1.63; 1302 women; 9 studies) both low-quality evidence.Balloon versus low-dose oral misoprostol: a balloon catheter probably increases the risk of a vaginal delivery not achieved within 24 hours (RR 1.28, 95% CI 1.13 to 1.46; 782 women, 2 studies, and probably slightly increases the risk of a caesarean section (RR 1.17, 95% CI 1.04 to 1.32; 3178 women; 7 studies; both moderate-quality evidence) when compared to oral misoprostol. It is uncertain whether there is a difference in uterine hyperstimulation with FHR changes (RR 0.81, 95% CI 0.48 to 1.38; 2033 women; 2 studies), serious neonatal morbidity or perinatal death (RR 1.11, 95% CI 0.60 to 2.06; 2627 women; 3 studies), both low-quality evidence, serious maternal morbidity or death (RR 0.50, 95% CI 0.05 to 5.52; 2627 women; 3 studies), very low-quality evidence, five-minute Apgar scores < 7 (RR 0.71, 95% CI 0.38 to 1.32; 2693 women; 4 studies) and NICU admissions (RR 0.82, 95% CI 0.58 to 1.17; 2873 women; 5 studies) both low-quality evidence.

AUTHORS' CONCLUSIONS

Low- to moderate-quality evidence shows mechanical induction with a balloon is probably as effective as induction of labour with vaginal PGE2. However, a balloon seems to have a more favourable safety profile. More research on this comparison does not seem warranted.Moderate-quality evidence shows a balloon catheter may be slightly less effective as oral misoprostol, but it remains unclear if there is a difference in safety outcomes for the neonate. When compared to low-dose vaginal misoprostol, low-quality evidence shows a balloon may be less effective, but probably has a better safety profile.Future research could be focused more on safety aspects for the neonate and maternal satisfaction.

Double-balloon catheter versus dinoprostone insert for labour induction: a meta-analysis

OBJECTIVE

To assess the efficacy and safety of a double-balloon catheter versus dinoprostone insert for labour induction.

STUDY DESIGN

PubMed, MEDLINE, Embase, ClinicalTrials.gov, and the Cochrane Central Register of Clinical Trials databases were searched from 1985 to April 2018. Randomized controlled trials that compared a double-balloon catheter and dinoprostone insert for cervical ripening were identified. Eligible study populations consisted of women with singleton pregnancies that had any indication for labour induction and were randomly assigned to undergo induction with a double-balloon catheter or dinoprostone insert. The main outcomes were incidence of vaginal delivery within 24 h and caesarean section, and neonatal outcomes.

RESULTS

Five randomized trials (603 women; 305 with a double-balloon catheter and 298 with a dinoprostone insert) were eligible for inclusion. No differences were observed between the two groups in terms of vaginal delivery within 24 h [relative risk (RR) 1.21, 95% confidence interval (CI) 0.93-1.59] and incidence of caesarean section (RR 0.99, 95% CI 0.77-1.27). Compared with the double-balloon catheter, the dinoprostone insert was associated with a reduced need for oxytocin administration in the process of labour induction (RR 1.95, 95% CI 1.45-2.62). However, there was a higher incidence of excessive uterine activity (RR 0.17, 95% CI 0.06-0.54) and neonatal umbilical cord arterial blood pH < 7.1 (RR 0.36, 95% CI 0.15-0.84) in the dinoprostone insert group.

CONCLUSION

This review showed that the efficacy of labour induction using both the double-balloon catheter and dinoprostone insert was similar. However, the double-balloon catheter seemed to be a safer method.

Challenges and Limitations of Clinical Trials on Labor Induction: A Review of the Literature

Induction of labor is a common obstetric procedure performed in nearly a quarter of all deliveries in the United States. Pharmacological (prostaglandins, oxytocin) and/or mechanical methods (balloon catheters) are commonly used for labor induction; however, there is ongoing debate as to which method is the safest and most effective. This narrative review discusses key limitations of published trials on labor induction, including the lack of well-designed randomized controlled trials directly comparing specific methods of induction, heterogeneous trial populations, and wide variation in the protocols used and outcomes reported. Furthermore, the majority of published trials were underpowered to detect significant differences in the most clinically relevant efficacy and safety outcomes (e.g., cesarean delivery, neonatal mortality). By identifying the limitations of labor induction trials, we hope to highlight the importance of quality published data to better inform guidelines and drive evidence-based treatment decisions.

Patient satisfaction with the cervical ripening balloon as a method for induction of labour: a randomised controlled trial

INTRODUCTION

Evidence has shown that balloon catheters are as effective as prostaglandins (PGE) in achieving vaginal delivery within 24 hours of the start of induction of labour (IOL), with lower rates of uterine hyperstimulation, and similar Caesarean section and infection rates. International guidelines recommend mechanical methods as a method of IOL. We designed a prospective randomised controlled study to evaluate patient acceptance of the cervical ripening balloon (CRB) for IOL.

METHODS

Suitable women with a singleton term pregnancy without major fetal anomaly suitable for vaginal delivery were recruited and randomised to receive the CRB or PGE on the day of IOL. Characteristics of the women, labour and birth outcomes were obtained from case notes. Pain and satisfaction scores were obtained by interviewing the women at IOL and after delivery. The main outcome measures were participant characteristics, labour and birth outcomes, pain score, satisfaction scores, and whether the participant would recommend the mode of IOL.

RESULTS

There was no difference in the pain score between the two groups at the start of IOL, but thereafter, pain scores were lower in the CRB group compared to the PGE group (4.5 ± 2.3 vs. 5.6 ± 2.4, p = 0.044). Women were equally satisfied with both methods and equally likely to recommend their method for IOL.

CONCLUSION

Patient experience of IOL with CRB or PGE was equally satisfactory, although pain during induction was lower in the CRB group. We found that both methods of IOL are acceptable to women and should be made available to provide more options.

Risk of maternal, fetal and neonatal complications associated with the use of the transcervical balloon catheter in induction of labour: A systematic review

Induction of labour is one of the most frequently applied obstetrical interventions globally. Many studies have compared the use of balloon catheters with pharmacological agents. Although the safety of the balloon catheter is often mentioned, little has been written about the total spectrum of maternal and fetal morbidity associated with induction of labour using a balloon catheter. We evaluated the safety of labour induction with a transcervical balloon catheter by conducting a literature review with pooled risk assessments of the maternal, fetal and neonatal morbidity. We searched Medline, EMBASE and CINAHL as well as the Cochrane database using the Keywords 'induction of labour', 'cervical ripening', 'transcervical balloon', 'balloon catheter' and 'Foley balloon'. We did not use language or date restrictions. Randomized and quasi-randomized controlled trials as well as observational studies that contained original data on occurrence of maternal, fetal or neonatal morbidity during induction of labour with the balloon catheter were included. Studies were excluded if the balloon catheter was used concurrently with oxytocin and concurrently or consecutively with misoprostol, dinoprostone or extra-amniotic saline infusion. Study selection and quality assessment was performed by two authors independently using a standardized critical appraisal instrument. Outcomes were reported as weighted mean rates. We detected 84 articles reporting on 13,791 women. The overall risk of developing intrapartum maternal infection was 11.3% (912 of 8079 women), 3.3% (151 of 4538 women) for postpartum maternal infection and 4.6% (203 of 4460 women) for neonatal infection. Uterine hypercontractility occurred in 2.7% (148 of 5439) of the women. Uterine rupture after previous caesarean section occurred in 1.9% of women (26 of 1373), while other major maternal complications had an occurrence rate of <1%. The risk for developing minor maternal complications was <2%. The risk of developing a non-reassuring fetal heart rate was 10.8% (793 of 7336 women), 10.1% (507 of 5008 women) for fetal distress and 14.0% (460 of 3295 women) for meconium stained liquor. Neonatal death occurred in 0.29% (6 of 2058) of the deliveries and NICU admission in 7.2% (650 of 9065 deliveries). This review shows that labour induction with a balloon catheter is a safe intervention, with intrapartum maternal infection being the only reasonable risk above 10%.

Induction of Labor in Women with Oligohydramnios: Misoprostol Compared with Prostaglandin E2

Objective To compare perinatal outcomes in women with oligohydramnios and an unfavorable cervix undergoing labor induction with misoprostol to prostaglandin E2. Study Design We conducted a secondary analysis of women with oligohydramnios undergoing labor induction in the Consortium on Safe Labor study (2002-2008). Oligohydramnios was recorded in the medical chart. We evaluated perinatal outcomes. We limited the analysis to women with an unfavorable cervix defined by simplified Bishop score ≤ 4. Misoprostol was compared with prostaglandin E2. Women could have received oxytocin, underwent mechanical dilation, or had artificial rupture of membranes, but women who underwent induction with both misoprostol and prostaglandin E2 were excluded. We calculated adjusted odds ratios with 95% confidence intervals, controlling for maternal age, maternal body mass index (kg/m²), parity, and mechanical dilation. Results Among women with oligohydramnios and an unfavorable cervix who underwent induction of labor, 141 (39.4%) received misoprostol and 217 (60.6%) received prostaglandin E2. There were no significant differences in cesarean delivery, chorioamnionitis, postpartum hemorrhage, transfusion, neonatal intensive care unit (NICU) admission, NICU stay > 72 hours, mechanical ventilation, and neonatal sepsis. Conclusion In women with oligohydramnios and an unfavorable cervix, induction of labor with misoprostol was comparable to prostaglandin E2.

Double-balloon catheter versus prostaglandin E2 for cervical ripening and labour induction: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Induction of labour has become an increasingly common procedure. Ripening methods, including mechanical devices and pharmacological agents, improve the success rate of labour induction.

OBJECTIVE

To compare the efficacy and safety of the double-balloon catheter with prostaglandin E2 agents used for labour induction.

SEARCH STRATEGY

We searched electronic sources from MEDLINE, Embase and Web of Science, the Cochrane Library Database of Systematic Reviews, and ClinicalTrials.gov website.

SELECTION CRITERIA

Only randomised controlled trials comparing the PGE2 agents with the double-balloon catheter for cervical ripening and labour induction in women with unfavourable cervices were included in the analysis.

DATA COLLECTION AND ANALYSIS

The main outcomes included the vaginal delivery rate within 24 hours and risk of caesarean section. We calculated relative risks and mean differences using fixed- and random-effects models.

MAIN RESULTS

Nine studies (1866 patients) were included in this systematic review. Both the double-balloon catheter and PGE2 agents were comparable with regard to rate of caesarean section (RR 0.92; 95% CI 0.79, 1.07), vaginal delivery within 24 hours (RR 0.95; 95% CI 0.78, 1.16) and maternal adverse events, but the risk of excessive uterine activity (RR 10.02; 95% CI 3.99, 25.17) and need for neonatal intensive care unit admissions (RR 1.31; 95% CI 1.01, 1.69) were significantly increased in women who received PGE2 agents.

CONCLUSIONS

The double-balloon catheter demonstrated greater safety and cost-effectiveness than PGE2 agents for cervical ripening and labour induction. The efficacy profiles of both methods were similar.

TWEETABLE ABSTRACT

Double-balloon catheter versus prostaglandin E2 for cervical ripening and labour induction.

Intra-vaginal prostaglandin E2 versus double-balloon catheter for labor induction in term oligohydramnios

OBJECTIVE

Compare mechanical and pharmacological ripening for patients with oligohydramnios at term.

STUDY DESIGN

Fifty-two patients with oligohydramnios ⩽ 5 cm and Bishop score ⩽ 6 were randomized for labor induction with a vaginal insert containing 10 mg timed-release dinoprostone (PGE2) or double-balloon catheter. The primary outcome was time from induction to active labor. Time to labor, neonatal outcomes and maternal satisfaction were also compared.

RESULT

Baseline characteristics were similar. Time from induction to active labor (13 with PGE2 vs 19.5 h with double-balloon catheter; P = 0.243) was comparable, with no differences in cesarean rates (15.4 vs 7.7%; P = 0.668) or neonatal outcomes. The PGE2 group had higher incidence of early device removal (76.9 vs 26.9%; P = 0.0001), mostly because of active labor or non-reassuring fetal heart rate. Fewer PGE2 patients required oxytocin augmentation for labor induction (53.8 vs 84.6% P = 0.034). Time to delivery was significantly shorter with PGE2 (16 vs 20.5 h; P = 0. 045).

CONCLUSION

Intravaginal PGE2 and double-balloon catheter are comparable methods for cervical ripening in term pregnancies with oligohydramnios.