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 Clinicaltrials comparingmechanicalmethodsusedforthirdtrimester cervicalripeningorlabourinductionwithpharmacologicalmethods. 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 f

Induction of labor with a Foley catheter and the risk of subsequent preterm birth: A follow-up study of two randomized controlled trials (PROBAAT-1 and -2)

OBJECTIVE:The objective of this study was to evaluate the preterm birth rate in a subsequent pregnancy in women who had undergone term induction with a Foley catheter in comparison to induction with prostaglandins. METHODS:This was a follow-up study of two large randomized controlled trials. In the original trials (PROBAAT-1 and PROBAAT-2), women with a term, singleton pregnancy in cephalic presentation with an indication for labor induction were randomized to either a 30cc Foley catheter or prostaglandins (i.e. vaginal prostaglandin E2 in PROBAAT 1 and oral misoprostol in PROBAAT 2). The main outcome measures were preterm birth <37 weeks gestation and preterm birth <34 weeks gestation. Data were collected from hospital charts on subsequent pregnancies from hospitals participating in this follow-up study. RESULTS:14 hospitals agreed to participate in this follow-up study. Of the 1142 eligible women, 162 women (14%) were lost to follow-up. Of the 572 women randomized to a Foley catheter, 251 women had a subsequent pregnancy beyond 16 weeks gestation, versus 258 women of the 570 women who received prostaglandins. There were no differences in baseline characteristics. The overall preterm birth rate was 9/251 (3.6%) in the Foley catheter group versus 10/258 (3.9%) in the prostaglandin group (RR 0.93; 95%CI 0.38-2.24), with spontaneous preterm birth rates of 5/251 (2.0%) versus 5/258 (1.9%) respectively (RR 1.03, 95%CI 0.30-3.51). CONCLUSIONS:In women with a singleton term pregnancy, induction of labor with a 30cc Foley catheter is not associated with an increased risk of preterm birth in a subsequent pregnancy as compared to induction of labor with prostaglandins. This article is protected by copyright. All rights reserved.M. D. T. de Vaan, D. Blel, K. W. M. Bloemenkamp, M. Jozwiak, M. L. G. ten Eikelder ... B. W. Mol ... et al

Induction of labor with Foley catheter and risk of subsequent preterm birth: follow-up study of two randomized controlled trials (PROBAAT-1 and -2)

Objective: To evaluate the rate of preterm birth (PTB) in a subsequent pregnancy in women who had undergone term induction using a Foley catheter compared with prostaglandins. Methods: This was a follow-up study of two large randomized controlled trials (PROBAAT-1 and PROBAAT-2). In the original trials, women with a term singleton pregnancy with the fetus in cephalic presentation and with an indication for labor induction were randomized to receive either a 30-mL Foley catheter or prostaglandins (vaginal prostaglandin E2 in PROBAAT-1 and oral misoprostol in PROBAAT-2). Data on subsequent ongoing pregnancies > 16 weeks’ gestation were collected from hospital charts from clinics participating in this follow-up study. The main outcome measure was preterm birth 16 weeks' gestation in the Foley catheter and prostaglandin groups, respectively. There were no differences in baseline characteristics between the groups. The overall rate of PTB in a subsequent pregnancy was 9/251 (3.6%) in the Foley catheter group vs 10/258 (3.9%) in the prostaglandin group (relative risk (RR), 0.93; 95% CI, 0.38–2.24), and the rate of spontaneous PTB was 5/251 (2.0%) vs 5/258 (1.9%) (RR, 1.03; 95% CI, 0.30–3.51). Conclusion: In women with term singleton pregnancy, induction of labor using a 30-mL Foley catheter is not associated with an increased risk of PTB in a subsequent pregnancy, as compared to induction of labor using prostaglandins

The influence of various induction methods on adverse outcomes in small for gestational age neonates: A secondary analysis of the PROBAAT 1 and 2 trials.

OBJECTIVE: To evaluate the safety aspects of different induction methods in pregnancies with small-for-gestational-age neonates. STUDY DESIGN: This was a secondary analysis of two previously reported multicenter, randomized controlled trials conducted in the Netherlands. In the original trials, women were randomized to either a 30 cc Foley catheter, vaginal prostaglandin E2 (PROBAAT-1) or oral misoprostol (PROBAAT-2). A total of 425 patients with a term, singleton pregnancy in cephalic presentation with an indication for labor induction and a small-for-gestational-age neonate were included in this secondary analysis. Our primary outcome was a composed adverse neonatal outcome of Apgar score < 7 after 5 min and/or a pH in the umbilical artery < 7.05 and/or NICU admission. Secondary outcomes were mode of birth, operative birth for fetal distress and pH < 7.10 in the umbilical artery. For these outcome measures, multivariate as well as bivariate analyses were performed. RESULTS: An adverse neonatal outcome occurred in 4.7 % (10/214) induction with a Foley catheter, versus 12.8 % (19/149) after misoprostol (RR 0.36; 95 % CI 0.17-0.76) and 4.7 % (3/64) after Prostaglandin E2 (RR 0.98; 95 %CI 0.28-3.51). For individual components of the composed outcome of adverse events, a difference was found between a Foley catheter and misoprostol for Apgar score < 7 at 5 min (0.5 % versus 3.4; RR 0.14; 95 %CI 0.02-1.16) and NICU admission (1.9 % versus 6.1 %; RR 0.31; 0.10-0.97). No differences were found for mode of birth. CONCLUSIONS: For women who gave birth to a small-for-gestational-age neonate, a Foley catheter is probably a safer induction method compared to oral misoprostol