Mieke ten Eikelder

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.

Foley catheter or prostaglandin E2 inserts for induction of labour at term: an open-label randomized controlled trial (PROBAAT-P trial) and systematic review of literature

OBJECTIVE To assess the safety and effectiveness of a transcervical Foley catheter compared to vaginal prostaglandin E2 inserts for term induction of labour. STUDY DESIGN We conducted an open-label randomized controlled trial in five hospitals in the Netherlands. Women with a singleton term pregnancy in cephalic presentation, intact membranes, unfavourable cervix, and no prior caesarean section were enrolled. Participants were randomly allocated by a web-based randomization system to induction of labour with a 30 ml Foley catheter or 10mg slow-release vaginal prostaglandin E2 inserts in a 1:1 ratio. Due to the nature of the intervention this study was not blinded. The primary outcome was the caesarean section rate. Secondary outcomes were maternal and neonatal morbidity and time from intervention to birth. Additionally, we carried out a systematic review and meta-analysis of similar studies. RESULTS We analyzed 226 women: 107 received a Foley catheter and 119 inserts. Caesarean section rates were comparable (20% versus 22%, RR 0.90, 95% CI 0.54-1.50). Secondary outcomes showed no differences. We observed no serious maternal or neonatal morbidity. Meta-analysis showed comparable caesarean section rates, but significantly fewer cases of hyperstimulation during the ripening phase when a Foley catheter was used. CONCLUSIONS We found, in this relatively small study, no differences in effectiveness and safety of induction of labour with a Foley catheter and 10mg slow release vaginal prostaglandin E2 inserts. Meta-analysis confirmed a comparable caesarean section rate, and showed fewer cases of hyperstimulation when a Foley catheter was used.

Foley catheter versus vaginal misoprostol: randomized controlled trial (PROBAAT-M study) and systematic review and meta-analysis of literature

OBJECTIVES To assess effectiveness and safety of Foley catheter versus vaginal misoprostol for term induction of labor. STUDY DESIGN This trial randomly allocated women with singleton term pregnancy to 30-mL Foley catheter or 25-μg vaginal misoprostol tablets. Primary outcome was cesarean delivery rate. Secondary outcomes were maternal and neonatal morbidity and time to birth. Additionally, a systematic review was conducted. RESULTS Fifty-six women were allocated to Foley catheter, 64 to vaginal misoprostol tablets. Cesarean delivery rates did not differ significantly (25% Foley versus 17% misoprostol; relative risk [RR] 1.46, 95% confidence interval [CI] 0.72 to 2.94), with more cesarean deliveries due to failure to progress in the Foley group (14% versus 3%; RR 4.57, 95% CI 1.01 to 20.64). Maternal and neonatal outcomes were comparable. Time from induction to birth was longer in the Foley catheter group (36 hours versus 25 hours; p < 0.001). Meta-analysis showed no difference in cesarean delivery rate and reduced vaginal instrumental deliveries and hyperstimulation in the Foley catheter group. Other outcomes were not different. CONCLUSION Our trial and meta-analysis showed no difference in cesarean delivery rates and less hyperstimulation with fetal heart rate changes and vaginal instrumental deliveries when using Foley catheter, thereby supporting potential advantages of the Foley catheter over misoprostol as ripening agent.

Induction of Labor Using a Foley Catheter or Misoprostol: A Systematic Review and Meta-analysis.

Importance Induction of labor is a widely used obstetric intervention, occurring in one in four pregnancies. When the cervix is unfavorable, still many different induction methods are used. Objective We compared Foley catheter alone to different misoprostol dosages and administration routes, and the combination of Foley catheter with misoprostol. Evidence acquisition We reviewed the literature on the best induction method regarding their safety and effectiveness, using the outcome measures hyperstimulation, fetal distress, neonatal morbidity and mortality as well as cesarean delivery, vaginal instrumental delivery, and maternal morbidity. We searched Pubmed, Cochrane, and Web of Science from January 1, 1980 to February 12, 2016. Twenty-two randomized controlled trials (RCTs) were included, comparing Foley catheter with or without misoprostol to misoprostol alone (both vaginal and oral) for induction of labor (5,015 women). Results Most included studies were underpowered to detect differences in safety outcomes, as the majority are powered for time to delivery or cesarean delivery. Meta-analysis of these studies does not allow assessment of the safety profile of Foley catheter compared to misoprostol (any dose, any administration route) with sufficient power. For the safety outcomes of the total group of Foley catheter versus misoprostol (any dose, any administration route) (17 studies, 4,234 women) we found that Foley catheter results in less hyperstimulation compared to misoprostol (2% versus 4%; risk ratio [RR], 0.54; 95% confidence interval [CI], 0.37–0.79) and fewer cesarean deliveries for nonreassuring fetal heart rate, 5% vs 7%; RR, 0.72; 95% CI, 0.55–0.95; while there were no statistically significant differences in neonatal outcomes. The total number of cesarean deliveries was 26% versus 22% (RR, 1.16; 95% CI, 1.00–1.34). There were fewer vaginal instrumental deliveries with a Foley catheter compared to misoprostol (10% vs 14%; RR, 0.74; 95% CI, 0.60–0.91). Foley catheter with misoprostol compared to misoprostol alone (any dose, any administration route) (7 studies, 1,073 women) resulted in less hyperstimulation than misoprostol alone (17% vs 23%; RR, 0.71; 95% CI, 0.52–0.97). Cesarean deliveries for nonreassuring fetal heart rate were comparable (7% vs 9%; RR, 0.79; 95% CI, 0.51–1.22). Neonatal outcomes were infrequently reported. The total number of cesarean deliveries was 34% versus 34% (RR, 1.01; 95% CI, 0.86–1.19). Conclusion In women with an unripe cervix at term, Foley catheter seems to have a better safety profile than misoprostol (any dose, any administration route) for induction of labor. Larger studies are needed to investigate the safety profile of a Foley catheter compared to separate dosing and administration regimens of misoprostol. Target Audience Obstetricians and gynecologists, family physicians. Learning Objectives After completing this activity, the learner should be better able to: criticize the used primary outcome measures in many articles on induction of labor and thereby understand that a save delivery is more important than a fast one; appraise articles on induction of labor and understand that most studies are underpowered for important safety outcomes; select the safest induction method; and choose an induction method based on both safety and effectiveness outcomes.

Erratum to: Induction of labour with a Foley catheter or oral misoprostol at term: the PROBAAT-II study, a multicentre randomised controlled trial (vol 13, pg 67, 2013)

Additional author: During the editing process of the artDepartment of Obstetrics and Gynaecology, Maasstad Hospital, Rotterdam, the Netherlands. Department of Obstetrics and Gynaecology, Sint Lucas icle “Induction of labour with a Foley catheter or oral misoprostol at term: the PROBAAT-II study, a multicentre randomised controlled trial“ [1] an author has been accidentally removed from the author list. Gert J van Baaren (Department of Obstetrics and Gynecology, Academic Medical Centre, Amsterdam, the Netherlands, g.j.vanbaaren@amc.uva.nl) critically revised the first draft, and approved the final version of the manuscript. He was especially involved in the sections relating to the cost-effectiveness analysis.

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

When pregnancy complications pose a threat to the mother or fetus or both, induction of labor is often required. Induction of labor is accomplished through a variety of methods; in pregnant women having an unfavourable cervix, cervical ripening of the cervix is accomplished through various mechanical and pharmacological means. Oral misoprostol and Foley catheter are believed to be equally effective in women with an unfavorable cervix in accomplishing vaginal birth. The current open-label randomized noninferiority trial was conducted in pregnant women with a singleton gestation in 29 hospitals in the Netherlands (2012 to 2013) to directly compare oral misoprostol with Foley catheter. Women with a viable singleton pregnancy in cephalic presentation, intact membranes, gestational age of 37 weeks or more, and an unfavorable cervix were included in the trial. The women were then randomly allocated (1:1) to oral misoprostol (n = 932) or Foley catheter (n = 927). Oral misoprostol dosage given was 50 µg orally once every 4 hours with a maximum of 3 times a day. Placement of a 30-mL Foley catheter in the cervix was done either digitally or using a vaginal speculum. The results of the study showed that the primary outcome (asphyxia or postpartum hemorrhage) occurred in 12.2% women in the misoprostol group and in 11.5% women in the Foley catheter group (adjusted relative risk [RR], 1.06; 90% confidence interval [CI], 0.86–1.31). Cesarean delivery resulted in 16.8% of labors in the misoprostol group and in 20.1% of the time in the Foley catheter group (no significant difference between groups [RR, 0.84; 95% CI, 0.69–1.01]). When the indication for cesarean delivery was examined, fewer cesarean deliveries for failure to progress in the first stage occurred after induction in the misoprostol group than in the Foley catheter group (6.2% vs 10.6%; RR, 0.58; 95% CI, 0.42–0.79). In addition, operative vaginal delivery occurred more frequently in the misoprostol group. Among the misoprostol group spontaneous membrane rupture was more common and labor augmentation with oxytocin was less likely. The study leads to a conclusion that in terms of safety and effectiveness, induction of labour using oral misoprostol is as safe as mechanical induction using Foley catheter.