Induction of labour with a Foley catheter or oral misoprostol at term: the PROBAAT-II study, a multicentre randomised controlled trial

Cervical ripening balloon compared with vaginal dinoprostone for cervical ripening in obese women at term: A prospective cohort study

OBJECTIVE

To evaluate vaginal delivery in obese women who underwent cervical ripening at term using a dinoprostone vaginal insert or a cervical ripening balloon (CRB), and to assess maternal and neonatal morbidity according to the method.

METHODS

A prospective cohort study including obese women with a live singleton fetus in cephalic presentation who required cervical ripening at term (≥37 weeks) for maternal and/or fetal disease using a dinoprostone vaginal insert or a CRB. The primary outcome was vaginal delivery. Secondary outcomes were a favorable cervix (Bishop score >6) after 24 h, the time from device insertion to delivery, and composite maternal and neonatal morbidity.

RESULTS

In total, 135 consecutive women were analyzed (107 CRB, 79.3%; 28 dinoprostone vaginal insert, 20.7%). Vaginal delivery (86 [80.4%] after CRB vs 19 [67.9%] after dinoprostone vaginal insert; P = 0.248), favorable cervix within 24 h after device placement (52 [48.6%] vs 17 [60.7%]; P = 0.264), and maternal morbidity (12 [11.2%] vs 4 [14.3%]; P = 0.646) were similar between the groups. The time from device insertion to delivery also did not differ between the groups. Neonatal morbidity was significantly higher after the dinoprostone vaginal insert (11 [39.3%] vs 20 [18.7%]; P = 0.030). Cervical ripening using the dinoprostone vaginal insert, compared with the CRB, was significantly associated with neonatal morbidity (adjusted odds ratio 4.00, 95% confidence interval 1.34-12.5), but not with maternal morbidity (adjusted odds ratio 1.23, 95% confidence interval 0.30-4.38).

CONCLUSIONS

Vaginal delivery, a favorable cervix after 24 h, the time from device insertion to delivery, and maternal morbidity did not significantly differ between the CRB and the dinoprostone vaginal insert for cervical ripening in obese women at term. Nevertheless, neonatal morbidity was significantly associated with the dinoprostone vaginal insert, compared with the CRB, among obese women who required cervical ripening at term.

Dinoprostone vaginal insert compared to cervical ripening balloon as second line of cervical ripening after first dinoprostone insert

BACKGROUND AND PROBLEM

To compare dinoprostone vaginal insert (PG) with cervical ripening balloon (CRB) as second line of cervical ripening in women at term with a persistent unfavorable cervix after first PG.

METHODS

This retrospective cohort study comprised all women with singleton fetus in cephalic presentation who required cervical ripening at term (≥37 weeks) for maternal and/or fetal disease using repeated PG or CRB for a persistent unfavorable cervix (Bishop score <6) 24 h after first PG. Primary outcome was vaginal delivery rate. Secondary outcomes were favorable cervix (Bishop score ≥6) or labor within 24 h after second device placement, postpartum hemorrhage (PPH) and neonatal morbidity.

FINDINGS

180 women were analyzed (127 repeated PG (70.6 %) and 53 CRB after first PG (29.4 %)). After second device, 93.3 % of women had a favorable cervix (Bishop score ≥6) or were in labor within 24 h, and the rate was significantly higher after CRB, compared to repeated PG (98.1 % vs. 91.3 %; p = 0.048). Vaginal deliveries were similar between groups (62.2 % after repeated PG vs. 54.7 % after CRB; p = 0.36). PPH was observed in 22.2 % of included women, and no difference was observed between groups (21.3 % vs. 21.4 %; p = 0.63). Neonatal morbidity was similar between groups (13.4 % vs. 9.4 %; p = 0.48).

CONCLUSION

Vaginal delivery rate and neonatal morbidity were similar when using PG or CRB as second line in women at term with a persistent unfavorable cervix after first PG. CRB seemed to be more efficient on the cervix status, compared to repeated PG, in these women.

Predictive Factors for Successful Cervical Ripening among Women with Gestational Diabetes Mellitus at Term: A Prospective Study

The purpose of this prospective cohort study is to identify the predictive factors for vaginal delivery among women (n = 146) who underwent cervical ripening using a dinoprostone insert (PG) alone (13.7%), cervical ripening balloon (CRB) alone (52.7%), oral misoprostol (M) alone (4.1%), or repeated methods (R, 29.5%) for gestational diabetes mellitus (GDM) at term, and to analyze maternal and neonatal morbidity outcomes according to the method for cervical ripening. After cervical ripening, vaginal delivery occurred in 84.2% (n = 123) and was similar among groups (90.0% after PG, 83.1% after CRB, 83.3% after M, and 83.7% after R; p = 0.89). After a multivariable logistic regression analysis adjusted for potential confounders, the internal cervical os being open before cervical ripening was a predictor of vaginal delivery (adjusted odds ratio (OR) of 4.38, 95% confidence index (CI) of 1.62-13.3, p = 0.03), and previous cesarean delivery was a predictor of cesarean delivery (aOR of 7.67, 95% CI of 2.49-24.00, p < 0.01). Birthweight was also significantly associated with cesarean delivery (aOR of 1.15, 95% CI of 1.03-1.31, p = 0.02). The rates of maternal and neonatal morbidity outcomes were 10.9% (n = 16) and 19.9% (n = 29), respectively, and did not differ according to the mode of delivery and to the method used for cervical ripening. Identifying these specific high-risk women (previous cesarean delivery and internal cervical os being closed before cervical ripening) for cesarean delivery among women who underwent cervical ripening for GDM at term is important and practical for all physicians to make a decision in partnership with women.

Offering women a choice in induction of labour: a prospective cohort study

PURPOSE

To evaluate women's choice in the method of labour induction between oral misoprostol, PGE2 pessary and the Foley catheter. To compare women's satisfaction according to their choice and to identify factors associated with patient satisfaction.

METHODS

We conducted a comparative, prospective cohort study of 520 women who chose their preferred method for labour induction, in a French tertiary hospital, from July 2019 to October 2020. Before and after the delivery, they were asked to argue their choice and to evaluate their satisfaction through the use of questionnaires. The primary outcome was global level of satisfaction.

RESULTS

Of the 520 women included, 67.5% of women chose oral misoprostol compared to 21% PGE2 pessary and 11.5% Foley catheter. Regarding global satisfaction, we found no significant difference between the three groups: 78.4%, 68.8% and 71.2% (p = 0.107) for, respectively, oral misoprostol, PGE2 pessary and Foley catheter. Factors that seem to improve women's satisfaction were nulliparity (aOR = 2.03, 95% CI [1.19-3.53]), delivery within 24 h after the start of induction (aOR = 3.46, 95% CI [2.02-6.14]) and adequate information (aOR = 4.21, 95% CI [1.869.64]). Factors associated with lower satisfaction rates were postpartum haemorrhage (aOR = 0.51, 95% CI [0.30-0.88]) and caesarean section (aOR = 0.31, 95% CI [0.17-0.54]).

CONCLUSION

Women satisfaction rates were not different between the three methods, when chosen by the patients themselves. These finding should encourage caregivers to promote shared decision making when possible.

TRIAL REGISTRATION

The protocol was approved by the French ethics committee for research in obstetrics and gynaecology (CEROG, reference number 2019-OBS-0602) on 1st June 2019.

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.

Predictors of efficacy for cervical ripening among the Bishop score criteria in nulliparous women at term

OBJECTIVE

To determine predictors of efficacy for cervical ripening among the Bishop score criteria in nulliparous women at term.

METHOD

Prospective observational study of nulliparous women with singleton term fetuses in vertex presentation, intact membranes, and an unfavorable cervix (Bishop score < 6) who underwent cervical ripening with a cervical-ripening balloon (CRB; n = 47) or dinoprostone vaginal insert (PG; n = 28). The authors analyzed Bishop score criteria (dilatation, effacement, fetal station, consistency, position) before and after device removal. Primary outcome was favorable cervix (Bishop score ≥ 6) after device removal. Secondary outcomes were vaginal delivery, modification of Bishop score criteria, and perinatal morbidity.

RESULTS

Rates of favorable cervix after cervical ripening were similar between groups (66.7% with CRB vs. 59.3% with PG; P = 0.526). Vaginal delivery (76.6% vs. 78.6%; P = 0.843) and perinatal morbidity did not differ between groups. CRB appeared to be more effective than PG in increasing consistency (+0.7 ± 0.2 vs. +0.3 ± 0.2; P = 0.001) and dilatation of the cervix (+1.3 ± 0.3 vs. +0.9 ± 0.3; P = 0.005). No Bishop score criterion was found as a significant predictor for vaginal delivery.

CONCLUSION

CRB seems to be more effective than PG in increasing the consistency and dilatation of the cervix. Efficacy of CRB and PG for vaginal delivery was similar.

Prospective observational study investigating the effectiveness, safety, women’s experiences and quality of life at 3 months regarding cervical ripening methods for induction of labor at term—The MATUCOL study protocol

Background

The purposes of successful induction of labor (IOL) are to shorten the time for IOL to delivery, increase the vaginal delivery rate, and reduce the rate of maternal and neonatal morbidity. In cases of unfavorable cervix (Bishop score <6), cervical ripening is advised to improve vaginal delivery rate. It may be initiated by mechanical (double balloon catheter (DBC), synthetic osmotic dilator) or pharmacologic (prostaglandins) methods, and the problem is complex due to the multitude of cervical ripening methods. We are constantly looking for the optimal protocol of cervical ripening for each woman. The present study aims to elucidate whether cervical ripening method is associated with increase rate of vaginal delivery, good women’s experience and unaltered long-term quality of life after cervical ripening at term regarding maternal and obstetric characteristics.

Methods and design

The MATUCOL study is a monocentric, prospective, observational study of all consecutive women who required cervical ripening (Bishop score <6) using different methods (DBC, vaginal dinoprostone, oral misoprostol) with a live fetus at term (≥37 weeks) between January 2020 and August 2021. The outcomes will be mode of delivery, maternal and neonatal morbidity, discomfort/pain assessments during cervical ripening, women’s experience and satisfaction, and the impact of cervical ripening on the health-related quality of life at 3 months. If it reports a significant efficacy/safety/perinatal morbidity/women’s satisfaction/quality of life at 3 months post-delivery associated with a method of cervical ripening in a specific situation (gestational and/or fetal disease) using a multivariate analysis, its use should be reconsidered in clinical practice.

Discussion

This study will reveal that some cervical ripening methods will be more effectiveness, safe, with good women’s experiences and QOL at 3 months compared to others regarding maternal and obstetric characteristics.

Trial registration

This study is being performed at La Roche sur Yon Hospital following registration as GNEDS on January 8, 2020.

Low-dose oral misoprostol for induction of labour

BACKGROUND

Misoprostol given orally is a commonly used labour induction method. Our Cochrane Review is restricted to studies with low-dose misoprostol (initially ≤ 50 µg), as higher doses pose unacceptably high risks of uterine hyperstimulation.

OBJECTIVES

To assess the efficacy and safety of low-dose oral misoprostol for labour induction in women with a viable fetus in the third trimester of pregnancy.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov,  the WHO International Clinical Trials Registry Platform (14 February 2021) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised trials comparing low-dose oral misoprostol (initial dose ≤ 50 µg) versus placebo, vaginal dinoprostone, vaginal misoprostol, oxytocin, or mechanical methods; or comparing oral misoprostol protocols (one- to two-hourly versus four- to six-hourly; 20 µg to 25 µg versus 50 µg; or 20 µg hourly titrated versus 25 µg two-hourly static).

DATA COLLECTION AND ANALYSIS

Using Covidence, two review authors independently screened reports, extracted trial data, and performed quality assessments. Our primary outcomes were vaginal birth within 24 hours, caesarean section, and hyperstimulation with foetal heart changes.

MAIN RESULTS

We included 61 trials involving 20,026 women. GRADE assessments ranged from moderate- to very low-certainty evidence, with downgrading decisions based on imprecision, inconsistency, and study limitations. Oral misoprostol versus placebo/no treatment (four trials; 594 women) Oral misoprostol may make little to no difference in the rate of caesarean section (risk ratio (RR) 0.81, 95% confidence interval (CI) 0.59 to 1.11; 4 trials; 594 women; moderate-certainty evidence), while its effect on uterine hyperstimulation with foetal heart rate changes is uncertain (RR 5.15, 95% CI 0.25 to 105.31; 3 trials; 495 women; very low-certainty evidence). Vaginal births within 24 hours was not reported. In all trials, oxytocin could be commenced after 12 to 24 hours and all women had pre-labour ruptured membranes. Oral misoprostol versus vaginal dinoprostone (13 trials; 9676 women) Oral misoprostol probably results in fewer caesarean sections (RR 0.84, 95% CI 0.78 to 0.90; 13 trials, 9676 women; moderate-certainty evidence). Subgroup analysis indicated that 10 µg to 25 µg (RR 0.80, 95% CI 0.74 to 0.87; 9 trials; 8652 women) may differ from 50 µg (RR 1.10, 95% CI 0.91 to 1.34; 4 trials; 1024 women) for caesarean section. Oral misoprostol may decrease vaginal births within 24 hours (RR 0.93, 95% CI 0.87 to 1.00; 10 trials; 8983 women; low-certainty evidence) and hyperstimulation with foetal heart rate changes (RR 0.49, 95% CI 0.40 to 0.59; 11 trials; 9084 women; low-certainty evidence). Oral misoprostol versus vaginal misoprostol (33 trials; 6110 women) Oral use may result in fewer vaginal births within 24 hours (average RR 0.81, 95% CI 0.68 to 0.95; 16 trials, 3451 women; low-certainty evidence), and less hyperstimulation with foetal heart rate changes (RR 0.69, 95% CI 0.53 to 0.92, 25 trials, 4857 women, low-certainty evidence), with subgroup analysis suggesting that 10 µg to 25 µg orally (RR 0.28, 95% CI 0.14 to 0.57; 6 trials, 957 women) may be superior to 50 µg orally (RR 0.82, 95% CI 0.61 to 1.11; 19 trials; 3900 women). Oral misoprostol probably does not increase caesarean sections overall (average RR 1.00, 95% CI 0.86 to 1.16; 32 trials; 5914 women; low-certainty evidence) but likely results in fewer caesareans for foetal distress (RR 0.74, 95% CI 0.55 to 0.99; 24 trials, 4775 women). Oral misoprostol versus intravenous oxytocin (6 trials; 737 women, 200 with ruptured membranes) Misoprostol may make little or no difference to vaginal births within 24 hours (RR 1.12, 95% CI 0.95 to 1.33; 3 trials; 466 women; low-certainty evidence), but probably results in fewer caesarean sections (RR 0.67, 95% CI 0.50 to 0.90; 6 trials; 737 women; moderate-certainty evidence). The effect on hyperstimulation with foetal heart rate changes is uncertain (RR 0.66, 95% CI 0.19 to 2.26; 3 trials, 331 women; very low-certainty evidence). Oral misoprostol versus mechanical methods (6 trials; 2993 women) Six trials compared oral misoprostol to transcervical Foley catheter. Misoprostol may increase vaginal birth within 24 hours (RR 1.32, 95% CI 0.98 to 1.79; 4 trials; 1044 women; low-certainty evidence), and probably reduces the risk of caesarean section (RR 0.84, 95% CI 0.75 to 0.95; 6 trials; 2993 women; moderate-certainty evidence). There may be little or no difference in hyperstimulation with foetal heart rate changes (RR 1.31, 95% CI 0.78 to 2.21; 4 trials; 2828 women; low-certainty evidence). Oral misoprostol one- to two-hourly versus four- to six-hourly (1 trial; 64 women) The evidence on hourly titration was very uncertain due to the low numbers reported. Oral misoprostol 20 µg hourly titrated versus 25 µg two-hourly static (2 trials; 296 women) The difference in regimen may have little or no effect on the rate of vaginal births in 24 hours (RR 0.97, 95% CI 0.80 to 1.16; low-certainty evidence). The evidence is of very low certainty for all other reported outcomes.

AUTHORS' CONCLUSIONS

Low-dose oral misoprostol is probably associated with fewer caesarean sections (and therefore more vaginal births) than vaginal dinoprostone, and lower rates of hyperstimulation with foetal heart rate changes. However, time to birth may be increased, as seen by a reduced number of vaginal births within 24 hours. Compared to transcervical Foley catheter, low-dose oral misoprostol is associated with fewer caesarean sections, but equivalent rates of hyperstimulation. Low-dose misoprostol given orally rather than vaginally is probably associated with similar rates of vaginal birth, although rates may be lower within the first 24 hours. However, there is likely less hyperstimulation with foetal heart changes, and fewer caesarean sections performed due to foetal distress. The best available evidence suggests that low-dose oral misoprostol probably has many benefits over other methods for labour induction. This review supports the use of low-dose oral misoprostol for induction of labour, and demonstrates the lower risks of hyperstimulation than when misoprostol is given vaginally. More trials are needed to establish the optimum oral misoprostol regimen, but these findings suggest that a starting dose of 25 µg may offer a good balance of efficacy and safety.

Foley Bulb Added to an Oral Misoprostol Induction Protocol: A Cluster Randomized Trial

OBJECTIVE

To evaluate whether the induction of labor in term gravid women with cervical dilation 2 cm or less and intact membranes by using oral misoprostol preceded by transcervical Foley bulb placement results in a significantly increased vaginal delivery rate compared with the use of oral misoprostol alone.

METHODS

We randomized the induction method by week of admission to labor and delivery, with each week group described as a cluster in a block randomized design. Women with gestational age of 37 weeks or greater, cervical dilation 2 cm or less, intact membranes, and indication for labor induction were included. Study arms were either 100 micrograms of oral misoprostol after transcervical Foley bulb placement or 100 micrograms of oral misoprostol alone. The primary outcome was vaginal delivery with the first induction attempt. Secondary outcomes included time to delivery, clinical chorioamnionitis (maternal temperature of 38°C or greater during labor with or without fundal tenderness, without other identified cause), cesarean delivery indication, and adverse outcomes. We estimated that a sample size of 1,077 per arm was needed to detect a 5% increase in vaginal delivery rate with a type I error of 5% and power of 80%, accounting for interim analysis and cluster size of 30 inductions per week. This was a pragmatic trial, and analysis was by intention-to-treat.

RESULTS

From January 1, 2018, to May 13, 2019, 1,117 women (34 clusters) were assigned to oral misoprostol plus Foley and 1,110 women (34 clusters) to oral misoprostol alone. Demographic characteristics were similar. Vaginal delivery at the first induction occurred in 78% of the misoprostol plus Foley arm and in 77% of the misoprostol arm (relative risk [RR] 1.00; 95% CI 0.96-1.05; adjusted relative risk [aRR], 1.00; 95% CI 0.95-1.05). Clinical chorioamnionitis occurred in 18% of the misoprostol plus Foley arm and in 14% of the misoprostol arm (RR 1.30; 95% CI 1.07-1.58; aRR 1.30; 95% CI 1.08-1.56). There were no differences in neonatal outcomes.

CONCLUSION

Induction of labor in gravid women at term with intact membranes by using oral misoprostol plus Foley bulb did not result in a higher vaginal delivery rate, but it did result in more clinical chorioamnionitis compared with the use of oral misoprostol alone.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT03407625.

Intracervical Foley Catheter Plus Intravaginal Misoprostol vs Intravaginal Misoprostol Alone for Cervical Ripening: A Meta-Analysis

Currently, there is no meta-analysis comparing intravaginal misoprostol plus intracervical Foley catheter versus intravaginal misoprostol alone for term pregnancy without identifying risk factors. Therefore, the purpose of this study is to conduct a systematic review and meta-analysis of randomized control trials (RCTs) comparing concurrent intravaginal misoprostol and intracervical Foley catheter versus intravaginal misoprostol alone for cervical ripening. We systematically searched Embase, Pubmed, and Cochrane Collaboration databases for randomized controlled trials (RCTs) comparing intracervical Foley catheter plus intravaginal misoprostol and intravaginal misoprostol alone using the search terms "Foley", "misoprostol", "cervical ripening", and "induction" up to 29 January 2019. Data were extracted and analyzed by two independent reviewers including study characteristics, induction time, cesarean section (C/S), clinical suspicion of chorioamnionitis, uterine tachysystole, meconium stain, and neonatal intensive care unit (NICU) admissions. Data was pooled using random effects modeling and calculated with risk ratio (RR) and 95% confidence interval (CI). Pooled analysis from eight studies, including 1110 women, showed that labor induction using a combination of intracervical Foley catheter and intravaginal misoprostol decreased induction time by 2.71 h (95% CI -4.33 to -1.08, p = 0.001), as well as the risk of uterine tachysystole and meconium staining (RR 0.54, 95% CI 0.30-0.99 and RR 0.48, 95% CI 0.32-0.73, respectively) significantly compared to those using intravaginal misoprostol alone. However, there was no difference in C/S rate (RR 0.93, 95% CI 0.78-1.11) or clinical suspicion of chorioamnionitis rate (RR 1.22, CI 0.58-2.57) between the two groups. Labor induction with a combination of intracervical Foley catheter and intravaginal misoprostol may be a better choice based on advantages in shortening induction time and reducing the risk of uterine tachysystole and meconium staining compared to intravaginal misoprostol alone.

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.

Which method is best for the induction of labour? A systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

More than 150,000 pregnant women in England and Wales have their labour induced each year. Multiple pharmacological, mechanical and complementary methods are available to induce labour.

OBJECTIVE

To assess the relative effectiveness, safety and cost-effectiveness of labour induction methods and, data permitting, effects in different clinical subgroups.

METHODS

We carried out a systematic review using Cochrane methods. The Cochrane Pregnancy and Childbirth Group's Trials Register was searched (March 2014). This contains over 22,000 reports of controlled trials (published from 1923 onwards) retrieved from weekly searches of OVID MEDLINE (1966 to current); Cochrane Central Register of Controlled Trials (The Cochrane Library); EMBASE (1982 to current); Cumulative Index to Nursing and Allied Health Literature (1984 to current); ClinicalTrials.gov; the World Health Organization International Clinical Trials Registry Portal; and hand-searching of relevant conference proceedings and journals. We included randomised controlled trials examining interventions to induce labour compared with placebo, no treatment or other interventions in women eligible for third-trimester induction. We included outcomes relating to efficacy, safety and acceptability to women. In addition, for the economic analysis we searched the Database of Abstracts of Reviews of Effects, and Economic Evaluations Databases, NHS Economic Evaluation Database and the Health Technology Assessment database. We carried out a network meta-analysis (NMA) using all of the available evidence, both direct and indirect, to produce estimates of the relative effects of each treatment compared with others in a network. We developed a de novo decision tree model to estimate the cost-effectiveness of various methods. The costs included were the intervention and other hospital costs incurred (price year 2012-13). We reviewed the literature to identify preference-based utilities for the health-related outcomes in the model. We calculated incremental cost-effectiveness ratios, expected costs, utilities and net benefit. We represent uncertainty in the optimal intervention using cost-effectiveness acceptability curves.

RESULTS

We identified 1190 studies; 611 were eligible for inclusion. The interventions most likely to achieve vaginal delivery (VD) within 24 hours were intravenous oxytocin with amniotomy [posterior rank 2; 95% credible intervals (CrIs) 1 to 9] and higher-dose (≥ 50 µg) vaginal misoprostol (rank 3; 95% CrI 1 to 6). Compared with placebo, several treatments reduced the odds of caesarean section, but we observed considerable uncertainty in treatment rankings. For uterine hyperstimulation, double-balloon catheter had the highest probability of being among the best three treatments, whereas vaginal misoprostol (≥ 50 µg) was most likely to increase the odds of excessive uterine activity. For other safety outcomes there were insufficient data or there was too much uncertainty to identify which treatments performed 'best'. Few studies collected information on women's views. Owing to incomplete reporting of the VD within 24 hours outcome, the cost-effectiveness analysis could compare only 20 interventions. The analysis suggested that most interventions have similar utility and differ mainly in cost. With a caveat of considerable uncertainty, titrated (low-dose) misoprostol solution and buccal/sublingual misoprostol had the highest likelihood of being cost-effective.

LIMITATIONS

There was considerable uncertainty in findings and there were insufficient data for some planned subgroup analyses.

CONCLUSIONS

Overall, misoprostol and oxytocin with amniotomy (for women with favourable cervix) is more successful than other agents in achieving VD within 24 hours. The ranking according to safety of different methods was less clear. The cost-effectiveness analysis suggested that titrated (low-dose) oral misoprostol solution resulted in the highest utility, whereas buccal/sublingual misoprostol had the lowest cost. There was a high degree of uncertainty as to the most cost-effective intervention.

FUTURE WORK

Future trials should be powered to detect a method that is more cost-effective than misoprostol solution and report outcomes included in this NMA.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005116.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Comparing induction of labour with oral misoprostol or Foley catheter at term: cost-effectiveness analysis of a randomised controlled multi-centre non-inferiority trial

OBJECTIVE

To assess the costs of labour induction with oral misoprostol versus Foley catheter.

DESIGN

Economic evaluation alongside a randomised controlled trial.

SETTING

Obstetric departments of six tertiary and 23 secondary care hospitals in the Netherlands.

POPULATION

Women with a viable term singleton pregnancy in cephalic presentation, intact membranes, an unfavourable cervix (Bishop score <6) without a previous caesarean section, were randomised for labour induction with oral misoprostol (n = 924) or Foley catheter (n = 921).

METHODS

We performed economic analysis from a hospital perspective. We estimated direct medical costs associated with healthcare utilisation from randomisation until discharge. The robustness of our findings was evaluated in sensitivity analyses.

MAIN OUTCOME MEASURES

Mean costs and differences were calculated per women induced with oral misoprostol or Foley catheter.

RESULTS

Mean costs per woman in the oral misoprostol group and Foley catheter group were €4470 versus €4158, respectively [mean difference €312, 95% confidence interval (CI) -€508 to €1063]. Multiple sensitivity analyses did not change these conclusions. However, if cervical ripening for low-risk pregnancies in the Foley catheter group was carried out in an outpatient setting, with admittance to labour ward only at start of active labour, the difference would be €4470 versus €3489, respectively (mean difference €981, 95% CI €225-1817).

CONCLUSIONS

Oral misoprostol and Foley catheter generate comparable costs. Cervical ripening outside labour ward with a Foley catheter could potentially save almost €1000 per woman.

TWEETABLE ABSTRACT

Oral misoprostol or Foley catheter for induction of labour generates comparable costs.

Comparative study of titrated oral misoprostol solution and vaginal dinoprostone for labor induction at term pregnancy

OBJECTIVE

To evaluate effectiveness and safety of titrated oral misoprostol solution (OMS) in comparison with vaginal dinoprostone for cervix ripening and labor induction in term pregnant women.

METHODS

A multicenter randomized controlled trial of women with term singleton pregnancy with indications for labor induction; 481 participants were allocated to receive titrated OMS with different doses by hourly administration according to the procedure or insert vaginal dinoprostone for cervix ripening and labor induction to compare maternal outcomes including indication of labor induction, mode of outcome of delivery, maternal morbidity, and neonatal outcomes between two groups for evaluating the efficacy and safety of titrated oral misoprostol induction.

RESULT

Proportion of delivery within 12 h of titrated oral misoprostol is significantly less than vaginal dinoprostone (p = 0.03), but no difference of total vaginal delivery rate (p = 0.93); the mean time of first treatment to vaginal delivery was longer in OMS group (21.3 ± 14.5 h) compared with the vaginal dinoprostone group (15.7 ± 9.6 h). Although the proportion of cesarean section between the two groups showed no statistically significant difference, OMS group showed significantly lower frequency of uterine hyperstimulation, hypertonus, partus precipitatus and non-reassuring fetal heart rate than dinoprostone group. Neonatal outcomes were similar evaluating from Apgar score and NICU admission. Our study also showed that labor induction of women with cervix Bishop score ≤3 needed increased dosage of misoprostol solution.

CONCLUSION

Titrated OMS is as effective as vaginal dinoprostone in labor induction for term pregnant women, with safer effect for its lower rate of adverse effect for women.

Induction of labour at term with oral misoprostol versus a Foley catheter (PROBAAT-II): a multicentre randomised controlled non-inferiority trial

BACKGROUND

Labour is induced in 20-30% of all pregnancies. In women with an unfavourable cervix, both oral misoprostol and Foley catheter are equally effective compared with dinoprostone in establishing vaginal birth, but each has a better safety profile. We did a trial to directly compare oral misoprostol with Foley catheter alone.

METHODS

We did an open-label randomised non-inferiority trial in 29 hospitals in the Netherlands. Women with a term singleton pregnancy in cephalic presentation, an unfavourable cervix, intact membranes, and without a previous caesarean section who were scheduled for induction of labour were randomly allocated to cervical ripening with 50 μg oral misoprostol once every 4 h or to a 30 mL transcervical Foley catheter. The primary outcome was a composite of asphyxia (pH ≤7·05 or 5-min Apgar score <7) or post-partum haemorrhage (≥1000 mL). The non-inferiority margin was 5%. The trial is registered with the Netherlands Trial Register, NTR3466.

FINDINGS

Between July, 2012, and October, 2013, we randomly assigned 932 women to oral misoprostol and 927 women to Foley catheter. The composite primary outcome occurred in 113 (12·2%) of 924 participants in the misoprostol group versus 106 (11·5%) of 921 in the Foley catheter group (adjusted relative risk 1·06, 90% CI 0·86-1·31). Caesarean section occurred in 155 (16·8%) women versus 185 (20·1%; relative risk 0·84, 95% CI 0·69-1·02, p=0·067). 27 adverse events were reported in the misoprostol group versus 25 in the Foley catheter group. None were directly related to the study procedure.

INTERPRETATION

In women with an unfavourable cervix at term, induction of labour with oral misoprostol and Foley catheter has similar safety and effectiveness.

FUNDING

FondsNutsOhra.

The Renaissance of Transcervical Balloon Catheters for Cervical Ripening and Labour Induction

Due to rising rates of labour induction in industrialised countries, safe and effective methods of induction have once again become a focus of interest and research. Prostaglandins are effective for cervical ripening and induction of uterine contractions. They do, however, cause overstimulation of the uterus in up to 20 % of cases, sometimes causing changes in fetal heart rate. Transcervical balloon catheters provide an alternative to prostaglandins for labour induction and have been used for this purpose for almost 50 years. This induction method has experienced a recent renaissance in clinical practice that is reflected in an annually rising number of publications on its use. Balloon catheters allow gentle ripening of the cervix without causing uterine overstimulation. The two catheters available are the Foley catheter (off-label use) and the double balloon catheter, which is licensed for use in induction of labour. Both are as effective as prostaglandins, and do not increase the risk of infection to mother or child. Catheter induction also requires less monitoring compared to prostaglandins resulting in improved patient satisfaction. Balloon catheters provide a useful and promising option to achieve vaginal delivery despite failed prostaglandin induction. Intravenous oxytocin is nevertheless required in up to 85 % of cases for adequate induction/augmentation of contractions. Balloon catheters, vaginal PGE₂ and misoprostol are equally effective in the context of an unripe/unfavourable cervix, the rate of uterine hyperstimulation being significantly lower, and the need for oxytocin significantly higher for catheters. Balloon catheters are increasingly being used in combination or sequentially with oral/vaginal misoprostol, although there is currently inadequate published data on the subject. International guidelines recommend the use of balloon catheters for labour induction with an unripe cervix (also following previous caesarean section) as an alternative to prostaglandins, particularly when these are not available or are contraindicated.

Misoprostol-induced fever and genetic polymorphisms in drug transporters SLCO1B1 and ABCC4 in women of Latin American and European ancestry

AIM

Misoprostol, a prostaglandin analogue used for the treatment of postpartum hemorrhage and termination of pregnancy, can cause high fevers. Genetic susceptibility may play a role in misoprostol-induced fever.

SUBJECTS & METHODS

Body temperature of women treated with misoprostol for termination of pregnancy in the UK (n = 107) and for postpartum hemorrhage in Ecuador (n = 50) was measured. Genotyping for 33 single nucleotide polymorphisms in 15 candidate genes was performed. Additionally, we investigated the transport of radiolabeled misoprostol acid across biological membranes in vitro.

RESULTS

The ABCC4 single nucleotide polymorphism rs11568658 was associated with misoprostol-induced fever. Misoprostol acid was transported across a blood-brain barrier model by MRP4 and SLCO1B1.

CONCLUSION

Genetic variability in ABCC4 may contribute to misoprostol-induced fever in pregnant women. Original submitted 21 January 2015; Revision submitted 24 April 2015.