Foley Catheter or Oral Misoprostol for Induction of Labor in Women with Term Premature Rupture of Membranes: A Randomized Multicenter Trial

Combination Foley Catheter-Oxytocin versus Oxytocin Alone following Preterm Premature Rupture of Membranes

OBJECTIVE

 The benefit of mechanical ripening agents following preterm premature rupture of membranes (PPROM) has not been established. We sought to compare the time to delivery in women who received transcervical Foley catheter plus oxytocin infusion versus oxytocin infusion alone in patients with unfavorable cervices and PPROM.

STUDY DESIGN

 This is a retrospective cohort study of patients presenting with PPROM of a live, singleton gestation between 240/7 and 366/7 weeks' gestation from January 2005 to October 2018 at a single, tertiary care institution. Patients with an unfavorable cervical examination (≤2-cm dilation), no contraindication to labor and undergoing labor induction were analyzed. Time to delivery was analyzed using multivariable linear regression adjusting for cervical dilation at induction and nulliparity. Bivariate and multivariate analyses were used where appropriate.

RESULTS

 A total of 260 participants were included: 109 who received a Foley catheter and oxytocin (Foley/oxytocin) and 151 who had oxytocin alone. Demographic characteristics were similar between the two groups. Unadjusted time to delivery was significantly shorter in the oxytocin only group (Foley/oxytocin: 20.35 hours vs. oxytocin alone: 14.7 hours, p < 0.001). No differences in length of labor were detected after adjusting for cervical dilation at induction and nulliparity (p = 0.5). The unadjusted rate of cesarean delivery was higher in the combination Foley/oxytocin group (Foley/oxytocin: 16.5% vs. oxytocin alone: 7.3%, p = 0.03), but no differences were found in the adjusted analysis (p = 0.06). There were no differences in clinical chorioamnionitis rates between the two groups (Foley/oxytocin: 8.3% vs. oxytocin alone: 9.3%, p = 0.83). Furthermore, no significant differences were found in maternal and neonatal outcomes between the two groups.

CONCLUSION

 In patients with PROM, the use of a transcervical Foley catheter in addition to oxytocin is not associated with a shorter time to delivery compared with oxytocin alone.

KEY POINTS

· Transcervical Foley catheter did not shorten length of labor in PPROM.. · Transcervical Foley catheter did not increase infection risk.. · Pitocin alone can be used in PPROM population..

Comparison of Misoprostol with Foley Catheter vs Misoprostol alone for Cervical Ripening and Induction of Labor in Patients with Premature Rupture of Membrane: A Randomized Clinical Trial Study

Background

This study evaluates the effect of misoprostol alone in comparison with misoprostol with Foley catheter in preparing the cervix for induction of labor in women with premature rupture of the amniotic sac.

Materials and Methods

This randomized clinical trial study was performed from 2017 to 2019 on 206 pregnant women with singleton pregnancy and gestational age more than 36 weeks, whose rupture of the amniotic sac had occurred less than 12 hours and had a Bishop score less than 4. These women were randomly assigned to two groups of Foley catheters with misoprostol (intervention group, P = 103) or misoprostol alone (control group, P = 103) to induce labor. In both groups, sublingual misoprostol (25 micrograms) was administered at intervals of 4-6 hours. The collected data were analyzed by SPSS.21 software.

Results

There is no significant difference between age and Bishop score in the two groups (P = 0.19, P = 0.31, respectively). Lower doses (0 to 3) of misoprostol were used in the intervention group versus 0 to 5 doses in the control group (P = 0.001). Delivery time was shorter in the intervention group (10.83 hours vs. 13.10 hours in the control group, P = 0.001). Also, the probability of complications such as fever, tachysystole, and hospitalization of an infant in the neonatal intensive care unit (NICU) did not increase.

Conclusion

An intracervical Foley catheter with misoprostol is more effective in inducing labor in pregnancies with premature rupture of the membranes than using misoprostol alone and can be a safe and effective option.

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.

Evaluation of mechanical and nonmechanical methods of cervix ripening in women with premature rupture of membranes: a randomized controlled trial

BACKGROUND

Premature rupture of membranes occurs in 8% of pregnancies. In the absence of spontaneous labor, induction of labor is considered an appropriate strategy for term pregnant women with premature rupture of membranes. There are several approaches for preinduction cervical ripening, including mechanical methods, such as Foley catheterization, and nonmechanical methods, such as oral misoprostol.

OBJECTIVE

This study aimed to evaluate and compare the effects of oral misoprostol and Foley catheterization in pregnant women with premature rupture of membranes at ≥34 weeks of gestation who underwent induction of labor.

STUDY DESIGN

A randomized clinical trial was conducted. The inclusion criteria included nulliparous and multiparous pregnant women at ≥34 weeks of gestation with singleton pregnancies, cephalic presentation, and confirmed amniotic fluid leakage for more than 60 minutes. A total of 104 participants were randomly allocated into 2 groups, one receiving sublingual misoprostol and the other receiving transcervical Foley catheter for cervical ripening. The primary outcome was time from intervention to delivery, and the secondary outcomes included delivery method, maternal and neonatal results (chorioamnionitis, Apgar score, neonatal sepsis, and asphyxia), and arterial blood gas analysis of the umbilical cord.

RESULTS

The mean time from induction of labor to delivery (11.6±1.98 hours for Foley catheter vs 10.16±2.35 hours for misoprostol; P=.007) and the median duration of cervical ripening (4.5 hours [interquartile range, 0.0-6.0] for Foley catheter vs 4.0 hours [interquartile range, 1.5-6.0] for misoprostol; P=.04) were longer in the Foley catheter group than in the misoprostol group. There was no statistically significant difference in the cesarean delivery rate between the 2 groups (29.6% for Foley catheter vs 38.5% for misoprostol; P=.2). There was no case of chorioamnionitis or asphyxia in the 2 groups. There was no significant difference between the 2 groups in terms of umbilical cord pH and the 1- and 5-minute Apgar scores (P=.1, P=.4, and P=.1); nevertheless, these values were higher in the Foley catheter group. There was no statistically significant difference among additional secondary outcomes.

CONCLUSION

In premature rupture of membranes cases, cervical ripening with a Foley catheter was associated with a longer duration of ripening and time from induction to delivery than cervical ripening with misoprostol. The cesarean delivery rate and the maternal and neonatal infection rates were not different between these methods.

Evaluating misoprostol and mechanical methods for induction of labour: Scientific Impact Paper No. 68 April 2022

Increasingly, births around the world are started artificially using medications or other methods. This process is known as induction of labour. As it becomes more common, methods are needed to meet the different clinical needs and birth preferences of women. Induction of labour typically includes a combination of the medication dinoprostone inserted into the vagina, artificial rupture of membranes ('releasing the waters'), and synthetic oxytocin (hormone given via a drip). This paper reviews some of the methods less commonly used for induction in the UK, namely a drug called misoprostol, which can be given orally or vaginally, and 'mechanical' methods, where labour is started by stretching the cervix (neck of the womb), most commonly with a soft silicone tube with a balloon near the tip, filled with water. Low-dose oral misoprostol tablets are now commercially available in the UK. Other methods for labour induction are not reviewed in detail in this paper. The evidence suggests mechanical induction of labour (using a balloon catheter) and misoprostol are both at least as safe and effective as using the standard drug, dinoprostone. There is evidence to suggest a balloon catheter may reduce the chance of serious negative outcomes for babies when compared with dinoprostone, and that giving low-dose oral misoprostol results in fewer caesarean births. Where possible and after informed consent, the method of induction of labour should be personalised to suit the individual woman, her clinical condition, and the setting in which she is giving birth. Local contexts and resources also need to be taken into account. To date, research into women's perspectives and experiences of induction of labour have been significantly lacking.

Double Balloon Catheter (Plus Oxytocin) versus Dinoprostone Vaginal Insert for Term Rupture of Membranes: A Randomized Controlled Trial (RUBAPRO)

Background: The aim of this study is to demonstrate that a double balloon catheter combined with oxytocin decreases time between induction of labor and delivery (TID) as compared to a vaginal dinoprostone insert in cases of premature rupture of membranes at term. Methods: This is a prospective, randomized, controlled trial including patient undergoing labor induction for PROM at term with an unfavorable cervix in Clermont-Ferrand university hospital. We compared the double balloon catheter over a period of 12 h with adjunction of oxytocin 6 h after catheter insertion versus dinoprostone vaginal insert. After device ablation, cervical ripening continued only with oxytocin. The main outcome was TID. Secondary outcomes concerned delivery mode, as well as maternal and fetal outcome, and were adjusted for parity. Results: 40 patients per group were randomized. Each group had similar baseline characteristics. The study failed to demonstrate reduced TID (16.2 versus 20.2 h, ES = 0.16 (−0.27 to 0.60), p = 0.12) in the catheter group versus dinoprostone except in nulliparous women (17.0 versus 26.5 h, ES = 0.62 (0.10 to 1.14), p = 0.006). The rate of vaginal delivery <24 h significantly increased with combined induction (88.5% versus 66.6%, p = 0.03). No statistical difference was observed concerning caesarean rate (12.5% versus 17.5%, p > 0.05), chorioamnionitis (0% versus 2.5%, p = 1), postpartum endometritis, or maternal or neonatal outcomes. Procedure-related pain and tolerance to devices were found to be similar for the two methods. Interpretation: The double balloon catheter combined with oxytocin is an alternative for cervical ripening in case of PROM at term, and may reduce TID in nulliparous women.

Preterm and term prelabour rupture of membranes: A review of timing and methods of labour induction

Prelabour rupture of membranes (PROM) exposes both foetuses and mothers to the risk of infection. Induction of labour has been proposed to reduce this risk, but its neonatal and maternal risks and benefits must be balanced against those of expectant management (EM). Recent randomized studies of preterm PROM show that EM until 37 weeks of gestation is associated with lower overall neonatal morbidity. In term PROM, active management is associated with a shorter birth interval but not with lower rates of neonatal infection. Similar maternal and neonatal outcomes are reported regardless of whether induction uses oxytocin, PGE2, or oral misoprostol.

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.

Efficacy and safety of oral misoprostol vs transvaginal balloon catheter for labor induction: An observational study within the SWEdish Postterm Induction Study (SWEPIS)

INTRODUCTION

Induction of labor is increasing. A common indication for induction of labor is late term and postterm pregnancy at 41 weeks or more. We aimed to evaluate if there are any differences regarding efficacy, safety, and women's childbirth experience between oral misoprostol and transvaginal balloon catheter for cervical ripening in women with a low-risk singleton pregnancy and induction of labor at 41⁺⁰ to 42^{+0 to 1} weeks of gestation.

MATERIAL AND METHODS

In this observational study, based on data from the Swedish Postterm Induction Study (SWEPIS), a multicenter randomized controlled trial, a total of 1213 women with a low-risk singleton pregnancy at 41 to 42 weeks of gestation were induced with oral misoprostol (n = 744) or transvaginal balloon catheter (n = 469) at 15 Swedish delivery hospitals. The primary efficacy outcome was vaginal delivery within 24 h and primary safety outcomes were neonatal and maternal composite adverse outcomes. Secondary outcomes included time to vaginal delivery and mode of delivery. Women's childbirth experience was assessed with the Childbirth Experience Questionnaire (CEQ 2.0) and visual analog scale. We present crude and adjusted mean differences and relative risks (RR) with 95% CI. Adjustment was performed for a propensity score based on delivery hospital and baseline characteristics including Bishop score.

RESULTS

Vaginal delivery within 24 h was significantly lower in the misoprostol group compared with the balloon catheter group (46.5% [346/744] vs 62.7% [294/469]; adjusted RR 0.76 95% CI 0.640.89]). Primary neonatal and maternal safety outcomes did not differ between groups (neonatal composite 3.5% [36/744] vs 3.2% [15/469]; adjusted RR 0.77 [95% CI 0.31-1.89]; maternal composite 2.3% [17/744] vs 1.9% [9/469]; adjusted RR 1.70 [95% CI 0.58-4.97]). Adjusted mean time to vaginal delivery was increased by 3.8 h (95% CI 1.3-6.2 h) in the misoprostol group. Non-operative vaginal delivery and cesarean delivery rates did not differ. Women's childbirth experience was positive overall and similar in both groups.

CONCLUSIONS

Induction of labor with oral misoprostol compared with a transvaginal balloon catheter was associated with a lower probability of vaginal delivery within 24 h and a longer time to vaginal delivery. However, primary safety outcomes, non-operative vaginal delivery, and women's childbirth experience were similar in both groups. Therefore, both methods can be recommended in women with low-risk postdate pregnancies.

Foley catheter vs oral misoprostol for induction of labor: individual participant data meta-analysis

OBJECTIVE

To compare the effectiveness and safety of Foley catheter and oral misoprostol for induction of labor (IOL).

METHODS

The Cochrane Review on Mechanical Methods for Induction of Labour and Ovid MEDLINE, EMBASE via Ovid, Ovid Emcare, CINAHL Plus, ClinicalTrials.gov and Scopus, from inception to April 2019, were searched for randomized controlled trials (RCTs) comparing Foley catheter to oral misoprostol for IOL in viable singleton gestations. Eligible trials for which raw data were obtained were included and individual participant data meta-analysis was performed. Primary outcomes were vaginal birth, a composite of adverse perinatal outcome (including stillbirth, neonatal death, neonatal seizures, admission to the neonatal intensive care unit, severe respiratory compromise or meconium aspiration syndrome) and a composite of adverse maternal outcome (including admission to the intensive care unit, maternal infection, severe postpartum hemorrhage, maternal death or uterine rupture). The quality of the included RCTs was assessed using the Cochrane Risk of Bias 2 tool and the certainty of evidence was evaluated using the GRADE approach. A two-stage random-effects model was used for meta-analysis according to the intention-to-treat principle and interactions between treatment and baseline characteristics were assessed.

RESULTS

Of seven eligible trials, four provided individual participant data for a total of 2815 participants undergoing IOL, of whom 1399 were assigned to Foley catheter and 1416 to oral misoprostol. All four trials provided data for each of the primary outcomes in all 2815 women. Compared with those receiving oral misoprostol, Foley catheter recipients had a slightly decreased chance of vaginal birth (risk ratio (RR), 0.95 (95% CI, 0.91-0.99); I² , 2.0%; moderate-certainty evidence). A trend towards a lower rate of composite adverse perinatal outcome was found in women undergoing IOL using a Foley catheter compared with oral misoprostol (RR, 0.71 (95% CI, 0.48-1.05); I² , 14.9%; low-certainty evidence). Composite adverse maternal outcome did not differ between the groups (RR, 1.00 (95% CI, 0.97-1.03); I² , 0%; moderate-certainty evidence). Meta-analyses of effect modifications did not show significant interactions between intervention and parity or gestational age for any of the primary outcomes.

CONCLUSIONS

For women undergoing IOL, Foley catheter is less effective than oral misoprostol, as it was associated with fewer vaginal births. However, while we found no significant difference in maternal safety, Foley catheter induction may reduce adverse perinatal outcomes. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Evidence-based labor management: induction of labor (part 2)

Induction of labor is indicated for many obstetrical, maternal, and fetal indications. Induction can be offered for pregnancy at 39 weeks' gestation. No prediction method is considered sensitive or specific enough to determine the incidence of cesarean delivery after induction. A combination of 60- to 80-mL single-balloon Foley catheter for 12 hours and either 25-μg oral misoprostol initially, followed by 25 μg every 2-4 hours, or 50 μg every 4-6 hours (if no more than 3 contractions per 10 minutes or previous uterine surgery), or oxytocin infusion should be recommended for induction of labor. Adding membrane stripping at the beginning of induction should be considered. Once 5-6 cm of cervical dilation is achieved during the induction of labor, consideration can be given to discontinue oxytocin infusion if in use at that time and adequate contractions are present. Induction with oxytocin immediately (as soon as feasible) or up to 12 hours of term prelabor rupture of membranes if labor is not evident is recommended. Outpatient Foley ripening can be considered for low-risk women. Cesarean delivery should not be performed before 15 hours of oxytocin infusion and amniotomy if feasible and ideally after 18-24 hours of oxytocin infusion.

Term prelabor rupture of membranes: Foley catheter versus dinoprostone as ripening agent

INTRODUCTION

Term prelabor rupture of membranes (TPROM) occurs in approximately 8 % of pregnancies. This condition regularly requires medical intervention such as induction of labor. The actual data concerning cervical ripening in case of TPROM does not favor any of the available techniques. This is the first study comparing dinoprostone versus Foley catheter for cervical ripening in TPROM.

MATERIALS AND METHODS

We conducted a retrospective before-after study. We enrolled all the patients with confirmed TPROM after 37 weeks of gestation (WG) who required cervical ripening. Women were included if they had a singleton fetus in cephalic presentation, with unfavorable cervix (Bishop ≤ 6). Patients were excluded if they had a previous uterine surgery, a multiple pregnancy, contraindication to vaginal delivery, spontaneous labor or favorable cervix (Bishop > 6). During the first period (2015), the protocol of cervical ripening involved dinoprostone (prostaglandins E2) by vaginal administration (vaginal gel or pessary). During the second period (2016-2017), the protocol of cervical ripening involved Foley catheter (FC). The primary outcome was the rate of cesarean section.

RESULTS

Two hundred and thirty-eight patients were included for the analysis: 131 in the first period (dinoprostone group) and 107 in the second period (foley catheter group). There was no significant difference between the two groups regarding the mode of delivery (cesarean section: 206 % vs 13 %, p = 016). Concerning tolerance, the were no difference in the rates of postpartum hemorrhage, maternal per-partum fever and endometrisis. Neonatal outcomes were similar between the two groups. The induction to delivery interval was lower with dinoprostone (20,3 h versus 26,0 h, p = 0001). The mean duration of labor was also significantly different (6,9 h for dinoprostone group versus 8,7 h for FC group, p = 001).

CONCLUSION

Cervical ripening in case of TPROM after 37 W G with Foley catheter seems to be a safe technique with similar outcomes to prostaglandins regarding the mode of delivery.

Can we induce labor by mechanical methods following preterm premature rupture of membranes?

OBJECTIVE

To evaluate the use of the intracervical balloon compared with locally applied prostaglandins for cervical ripening for induction in patients with preterm premature rupture of membranes.

METHODS

Monocentric, retrospective (from 2002 to 2017) observational cohort study of singleton pregnancies complicated by preterm premature rupture of membranes and induced between 34 and 37 weeks. The primary outcome measure was balloon catheter efficiency evaluated by Cesarean section rate. Secondary outcomes were : interval from induction to delivery, labor duration, oxytocin use, intrauterine infection rate, maternal complications (i.e., postpartum hemorrhage and endometritis), and neonatal complications.

RESULTS

60 patients had cervical ripening with prostaglandins alone and 58 had balloon catheter. Demographic characteristics were similar between the groups, except for induction term and neonatal weight. There was not a significant difference in occurrence of Cesarean section rate (p = 0.14). Nor were there significant differences in time from induction to birth (p = 0.32) or in intrauterine infection rate (p = 0.95). Labor duration was shorter (p = 0.006) and total oxytocin dose lower (p = 0.005) in patients induced by prostaglandins alone. Concerning neonatal outcomes, there were more transfers to intensive care (p = 0.008) and more respiratory distress (p = 0.005) among newborns induced by prostaglandins.

CONCLUSION

Compared with locally applied prostaglandins, balloon catheter induction is not associated with an increase of Cesarean section rate in patients with preterm premature rupture of membranes.

Oral Misoprostol for Induction of Labour in Term PROM: A Systematic Review

OBJECTIVE

To assess the efficacy of oral misoprostol for induction of labour (IOL) in the context of term pre-labour rupture of membranes (TPROM), and to assess pregnancy outcomes following the administration of oral misoprostol.

DATA SOURCES

A systematic literature search was performed using Ovid Medline, Embase, PubMed, and the Cochrane Database of Systematic Reviews.

STUDY SELECTION

Eligible studies were quasi-experimental trials or randomized controlled trials involving the use of oral misoprostol in singleton cephalic term pregnancies with confirmed rupture of membranes and no spontaneous labour at the time of membranes rupture, in mothers with no contraindications to vaginal delivery. Studies were excluded if they utilized vaginal misoprostol, excluded primigravid participants, or if the full text of the article was not accessible in English.

DATA EXTRACTION

Data were extracted by two reviewers using a standardized data extraction form. Study quality was assessed using the modified Jadad score.

DATA SYNTHESIS

Twelve randomized controlled trials that included 1489 singleton pregnancies were included. Doses of oral misoprostol ranged from 20 to 200 μg. The incidence of vaginal birth ranged from 73.0%-95.0% in the oral misoprostol group compared with 52.4%-94% in the control group. Hyperstimulation was infrequent, ranging from 0% to 13.8% in the oral misoprostol group compared with 0%-24% in the control group. Two trials, involving a total of 144 women that compared 50 μg of oral misoprostol every 4 hours versus expectant management followed by PGE₂ gel showed a higher incidence of vaginal birth with misoprostol (pooled risk ratio 1.33, 95% confidence interval 1.10-1.61).

CONCLUSION

Oral misoprostol appears to be a safe and effective for IOL in TPROM. However, the varying administration, dose, and frequency reported in the literature highlights the need to develop a standardized protocol for use in Canadian obstetrical practice.

Balloon catheter use for cervical ripening in women with term pre-labor rupture of membranes: A 5-year cohort study

INTRODUCTION

To investigate the safety of balloon catheter for cervical ripening in women with term pre-labor rupture of membranes (PROM) and to compare the incidence of maternal and neonatal infections in women with PROM and women with intact membranes undergoing cervical ripening with a balloon catheter.

MATERIAL AND METHODS

This retrospective cohort study of 1923 women with term singleton pregnancy and an unfavorable cervix undergoing cervical ripening with a balloon catheter was conducted in Helsinki University Hospital between January 2014 and December 2018. For each case of PROM, two controls were assigned. The main outcome measures were the rates of maternal and neonatal infections. Statistical analyses were performed by SPSS.

RESULTS

In all, 641 (33.3%) women following PROM and 1282 (66.6%) women with intact amniotic membranes underwent labor induction. The rates of intrapartum infection (3.7% vs 7.7%; P = .001) and neonatal infection (1.7% vs 3.8%; P = .01) were not increased in women induced by balloon catheter following PROM. Intrapartum infections were associated with nulliparity (odds ratio [OR] 3.3, 95% confidence interval [CI] 1.6-6.5), history of previous cesarean section (OR 2.8, 95% CI 1.2-6.4), extended gestational age ≥41 weeks (OR 1.9, 95% CI 1.2-3.0) and an induction to delivery interval of 48 hours or more (OR 2.0, 95% CI 1.2-3.3). The risk of neonatal infection was associated with nulliparity (OR 3.3, 95% CI 1.4-8.0), gestational age ≥41 weeks (OR 1.9, 95% CI 1.09-3.36) and induction to delivery interval of 48 hours or more (OR 3.4, 95% CI 1.9-6.0).

CONCLUSIONS

Use of balloon catheter in women with term PROM appears safe and was not associated with increased maternal or neonatal infectious morbidity.

MEchanical DIlatation of the Cervix-- in a Scarred uterus (MEDICS): the study protocol of a randomised controlled trial comparing a single cervical catheter balloon and prostaglandin PGE2 for cervical ripening and labour induction following caesarean delivery

INTRODUCTION

Labour induction in women with a previous caesarean delivery currently uses vaginal prostaglandin E2 (PGE2), which carries the risks of uterine hyperstimulation and scar rupture. We aim to compare the efficacy of mechanical labour induction using a transcervically applied Foley catheter balloon (FCB) with PGE2 in affected women attempting trial of labour after caesarean (TOLAC).

METHODS AND ANALYSIS

This single-centre non-inferiority prospective, randomised, open, blinded-endpoint study conducted at an academic maternity unit in Singapore will recruit a total of 100 women with one previous uncomplicated caesarean section and no contraindications to vaginal delivery. Eligible consented participants with term singleton pregnancies and unfavourable cervical scores (≤5) requiring labour induction undergo stratified randomisation based on parity and are assigned either FCB (n=50) or PGE2 (n=50). Treatments are applied for up to 12 hours with serial monitoring of the mother and the fetus and serial assessment for improved cervical scores. If the cervix is still unfavourable, participants are allowed a further 12 hours' observation for cervical ripening. Active labour is initiated by amniotomy at cervical scores of ≥6. The primary outcome is the rate of change in the cervical score, and secondary outcomes include active labour within 24 hours of induction, vaginal delivery, time-to-delivery interval and uterine hyperstimulation. All analyses will be intention-to-treat. The data generated in this trial may guide a change in practice towards mechanical labour induction if this proves efficient and safer for women attempting TOLAC compared with PGE2, to improve labour management in this high-risk population.

ETHICS AND DISSEMINATION

Ethical approval is granted by the Domain Specific Review Board (Domain D) of the National Healthcare Group, Singapore. All adverse events will be reported within 24 hours of notification for assessment of causality. Data will be published and will be available for future meta-analyses.

TRIAL REGISTRATION NUMBER

NCT03471858; Pre-results.

A comparison between induction of labor with 3 methods of titrated oral misoprostol, constant dose of oral misoprostol and Foley catheter with extra amniotic saline infusion (EASI), in women with unfavorable cervix

Background: Different methods of cervical ripening and induction of labor have been used in the cases of unfavorable cervix with different levels of success, but no method has been found to be the best option. The purpose of the present study was to find the effects and side effects of three different methods of cervical ripening and induction of labor. These three methods were oral titrated misoprostol, constant dose of oral misoprostol and Foley catheter with extra-amniotic saline infusion.

Methods: This clinical trial was performed on women with unfavorable cervix who had been admitted in Akbarabadi Teaching Hospital for induction of labor and had bishop score of less than six; between March 2014- March 2015. The eligible women were assigned into three groups. In titrated oral misoprostol group (n=33), titrated solution of misoprostol, and in oral misoprostol group (n=33), 50µg oral misoprostol every four hours and in Foley catheter group (n=50), Foley catheter with extra-amniotic saline infusion were administered. The main outcome was the number of vaginal deliveries during the first 24 hours. In addition, number of cesarean deliveries and adverse effects were compared between the three groups. The obtained data were analyzed using SPSS 18 software. Data analysis was performed according to the intention to treat principle. Chi-square test, Fisher Exact test, Student ttest, and Mann-Whitney U test, were used for comparing data. P-value≤0.05 was considered statistically significant.

Results: The three groups did not have any significant difference according to maternal age, gestational age at the time of admission, gravidity, parity, and primary Bishop Score. There was no significant difference between the three groups for the main outcome, which was vaginal delivery during the first 24 hours (p=0.887). There was no significant difference between the three groups according to hypertonicity, uterine hyperstimulation, meconium passage, non-reassuring fetal heart rate, neonatal Apgar score in minutes one and 5, and mean duration of beginning the intervention up to delivery. However, uterine tachysystole and NICU admission were more in the group to whom the titrated solution of misoprostol was administered (p=0.002 and p=0.037 respectively). The number of cesarean deliveries due to failure to progress was higher in the EASI group. However, EASI group showed the least number of none-reassuring fetal heart rate between the three groups. Meconium passage was more in the titrated misoprostol group, but the difference was not significant.

Conclusion: All three methods are appropriate methods for induction of labor in the cases of unfavorable cervix; and choosing each method depends on the expertise of labor staff, accessibility to the medications, cost, and taking care for monitoring the patients and adverse effects.

[Term Prelabor Rupture of Membranes: CNGOF Guidelines for Clinical Practice - Methods for Inducing Labor]

OBJECTIVES

To assess the studies comparing induction methods in women with term prelabor rupture of the membranes and establish if one is superior to the others.

METHODS

The MedLine database, the Cochrane Library and the recommendations from the French and foreign obstetrical societies or colleges have been consulted.

RESULTS

The included studies compared medical induction methods: oxytocin (intravenous), dinoprostone (vaginal gel, pessary or intracervical gel), and misoprostol (oral or vaginal route); and a mechanical induction method: the Foley catheter. The primary outcome measures were: labor induction to delivery interval, number of women delivered within 12 or 24hours of initiation of induction and cesarean delivery rate. The small sample size of the included studies as well as the limited number of reported complications does not provide a reasonable basis for concluding on the secondary outcome measures: pyrexia, chorioamnionitis, uterine tachysystole, Apgar scores of<7 at 5minutes. Induction of labor with misoprostol (oral and vaginal) reduced the labor induction to delivery interval compared with dinoprostone (LE2). This interval was unchanged when comparing induction with oxytocin and Foley catheter (LE2). The data comparing this interval in women induced with dinoprostone versus oxytocin and misoprostol versus oxytocin is limited or inconsistent. The cesarean delivery rate was comparable in women induced with dinoprostone (vaginal gel) versus oxytocin (LE2), misoprostol (oral and vaginal route) versus oxytocin (LE2), Foley catheter versus oxytocin (LE2), misoprostol versus dinoprostone (LE2) and misoprostol versus Foley catheter (LE2). The number of women delivered within 24hours of initiation of induction was comparable when induced with oral misoprostol versus oxytocin (LE2) and Foley catheter versus oxytocin (LE2). There is a lack of data for this outcome when comparing dinoprostone versus oxytocin, vaginal misoprotsol versus oxytocin, and misoprostol (oral and vaginal) versus dinoprostone. No induction method is superior to another for nulliparous women or women with unfavorable cervix (LE2).

CONCLUSION

The superiority of an induction method, in terms of effectiveness or safety, could not be established with the current available data for women with term prelabor rupture of the membranes. An increased risk of chorioamnionitis due to induction using Foley catheter could not be ruled out by the available data. All medical methods are suitable for inducing women with term prelabor rupture of the membranes (Grade B).

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.

Induction of labour in case of premature rupture of membranes at term with an unfavourable cervix: protocol for a randomised controlled trial comparing double balloon catheter (+oxytocin) and vaginal prostaglandin (RUBAPRO) treatments

INTRODUCTION

Premature rupture of membranes (PROM) occurs at term in 8% of pregnancies. Several studies have demonstrated that the risk of chorioamnionitis and neonatal sepsis increases with duration of PROM. Decreasing the time interval between PROM and delivery is associated with lower rates of maternal infections. In case of an unfavourable cervix, the use of prostaglandin for cervical maturation demonstrates some advantages over oxytocin. The use of double balloon catheter in reduction of PROM duration has not been evaluated in the literature.

METHODS AND ANALYSIS

We are conducting a prospective, monocentric, randomised clinical trial on pregnant women with an unfavourable cervix showing PROM at term (RUBAPRO).After 12-24 hours of PROM, women are randomly assigned to one group treated with a double balloon catheter for 12 hours, with oxytocin administered after 6 hours or to the control group treated with 24 hours of vaginal prostaglandin followed by oxytocin infusion alone. Patients (n=80) are randomised at a 1:1 ratio with stratification on parity.The inclusion criteria are a Bishop score of <6, cephalic presentation at term and confirmed PROM. Women with suspected chorioamnionitis; group B streptococcus (GBS) carrier; a history of caesarean delivery or any contraindication for vaginal delivery are excluded.The time from induction to delivery is the primary outcome. Secondary outcomes were mode of delivery, maternofetal morbidity and the effect of parity on strategies for reduction of PROM duration.To sufficiently demonstrate a difference (10 hours) between groups-with a statistical power of 90% and a two-tailed α of 5%-40 patients per group will be required.

ETHICS AND DISSEMINATION

Written informed consent is required from participants.National Ethics Committee approval was obtained in August 2017. The results will be published in a peer-reviewed journal and presented at relevant conferences. Access to raw data will be available only to members of the research team.

TRIAL REGISTRATION NUMBER

NCT03310333.

Foley Plus Oxytocin Compared With Oxytocin for Induction After Membrane Rupture: A Randomized Controlled Trial

OBJECTIVE

To evaluate the use of a transcervical Foley catheter plus oxytocin infusion compared with oxytocin infusion alone for labor induction and cervical ripening in women 34 weeks of gestation or greater with prelabor rupture of membranes.

METHODS

This is a randomized, multicenter trial of women with a live, singleton gestation at 34 weeks of gestation or greater with prelabor rupture of membranes, an unfavorable cervical examination (less than or equal to 2 cm dilated and less than or equal to 80% effaced), and no contraindication to labor. Participants were randomly allocated to a transcervical Foley catheter inflated to 30 cc with concurrent oxytocin infusion or oxytocin infusion alone. Oxytocin administration was standardized across sites. The primary study outcome was interval from induction to delivery. To detect a 2.5-hour difference in the interval from induction to delivery, we required outcome data on 194 women, assuming 80% power and a two-tailed α of 5%. Analysis was by intent to treat.

RESULTS

We enrolled 201 women: 93 were allocated to Foley and 108 to oxytocin. Demographics were similar between the groups. Time to delivery was not significantly different between groups: in the Foley group, it was 13.9 hours (±6.9 SD) compared with 14.4 hours (±7.9 SD) in the oxytocin group (P=.69). There were more cases of clinical chorioamnionitis (8% compared with 0%, P<.01) in the Foley group compared with the oxytocin group. There were no differences for other infectious morbidities or any other variable studied.

CONCLUSION

In patients with prelabor rupture of membranes, the use of a transcervical Foley catheter in addition to oxytocin does not shorten the time to delivery compared with oxytocin alone, but may increase the incidence of intraamniotic infection.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT01973036.

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 by Foley catheter compared with spontaneous onset of labor after previous cesarean section: a cohort study

OBJECTIVE

To evaluate the safety of induction of labor (IOL) with Foley catheter (FC) in women with a history of previous cesarean section (CS) and to assess risk factors for repeat CS and adverse maternal outcomes.

STUDY DESIGN

Cohort study of 1559 women with a history of previous CS in Helsinki University Hospital, Finland between 2013 and 2014.

RESULTS

Three hundred and sixty-one women (23.2%) underwent IOL by FC and 1198 (76.8%) had spontaneous onset of labor. The rate of repeat CS was higher in women undergoing IOL (38% vs 20.2%; P<0.001). The overall rate of uterine rupture was 0.3% in induced labor and 0.8% in spontaneous onset of labor (P=0.47). Adverse maternal outcomes were not significantly different. The intrapartum and postpartum infection rates were higher in women undergoing IOL compared with spontaneous onset of labor (6.1% vs 1.8%; P>0.001 and 5.3% vs 1.3%; P<0.001, respectively).

CONCLUSION

FC appears safe and effective method for IOL in women with a history of previous CS.