A prospective, randomized comparison of Foley catheter insertion versus intracervical prostaglandin E2 gel for preinduction cervical ripening

Methods for the induction of labor: efficacy and safety

This review assessed the efficacy and safety of pharmacologic agents (prostaglandins, oxytocin, mifepristone, hyaluronidase, and nitric oxide donors) and mechanical methods (single- and double-balloon catheters, laminaria, membrane stripping, and amniotomy) and those generally considered under the rubric of complementary medicine (castor oil, nipple stimulation, sexual intercourse, herbal medicine, and acupuncture). A substantial body of published reports, including 2 large network meta-analyses, support the safety and efficacy of misoprostol (PGE1) when used for cervical ripening and labor induction. Misoprostol administered vaginally at doses of 50 μg has the highest probability of achieving vaginal delivery within 24 hours. Regardless of dosing, route, and schedule of administration, when used for cervical ripening and labor induction, prostaglandin E2 seems to have similar efficacy in decreasing cesarean delivery rates. Globally, although oxytocin represents the most widely used pharmacologic agent for labor induction, its effectiveness is highly dependent on parity and cervical status. Oxytocin is more effective than expectant management in inducing labor, and the efficacy of oxytocin is enhanced when combined with amniotomy. However, prostaglandins administered vaginally or intracervically are more effective in inducing labor than oxytocin. A single 200-mg oral tablet of mifepristone seems to represent the lowest effective dose for cervical ripening. The bulk of the literature assessing relaxin suggests this agent has limited benefit when used for this indication. Although intracervical injection of hyaluronidase may cause cervical ripening, the need for intracervical administration has limited the use of this agent. Concerning the vaginal administration of nitric oxide donors, including isosorbide mononitrate, isosorbide, nitroglycerin, and sodium nitroprusside, the higher incidence of side effects with these agents has limited their use. A synthetic hygroscopic cervical dilator has been found to be effective for preinduction cervical ripening. Although a pharmacologic agent may be administered after the use of the synthetic hygroscopic dilator, in an attempt to reduce the interval to vaginal delivery, concomitant use of mechanical and pharmacologic methods is being explored. Combining the use of a single-balloon catheter with dinoprostone, misoprostol, or oxytocin enhances the efficacy of these pharmacologic agents in cervical ripening and labor induction. The efficacy of single- and double-balloon catheters in cervical ripening and labor induction seems similar. To date, the combination of misoprostol with an intracervical catheter seems to be the best approach when balancing delivery times with safety. Although complementary methods are occasionally used by patients, given the lack of data documenting their efficacy and safety, these methods are rarely used in hospital settings.

A randomized controlled trial of sequential vs simultaneous use of Foley balloon catheter and oxytocin for induction of labor in nulliparous pregnant women

BACKGROUND

Although recent evidence suggests the simultaneous approach use of oxytocin for induction of labor in nullipara, there is limited data from low-income settings that support this.

OBJECTIVE

This study aimed to determine whether induction of labor with simultaneous use of oxytocin and a Foley balloon catheter decreases the induction of labor to delivery interval in nulliparous women, compared with sequential use of a Foley balloon catheter followed by oxytocin.

STUDY DESIGN

This was a randomized controlled trial of nulliparous women with singleton pregnancies presenting for induction of labor at >28 weeks of gestation at St. Paul's Hospital Millennium Medical College (Addis Ababa, Ethiopia). The participants were randomly assigned to either the simultaneous group (the use of oxytocin and a Foley balloon catheter for induction of labor) or the sequential group (overnight intracervical Foley balloon catheter placement followed by the use of oxytocin the next morning). The primary outcome was induction of labor to delivery interval. Comparisons between the groups were made using the Student t test or Wilcoxon rank-sum test and chi-square test on Stata (version 15; StataCorp LLC, College Station, TX). This study is registered with the Pan African Clinical Trials Registry (identifier: PACTR201709002509200).

RESULTS

From November 2019 to March 2020, a total of 140 women were randomly assigned to the simultaneous group (70 women) or the sequential group (70 women). The median oxytocin initiation to delivery intervals were 6.09 hours (range, 4.03-10.7) in the sequential group and 8.1 hours (range, 4.7-11.6) in the simultaneous group (P=.46). The mean Foley balloon catheter insertion to delivery intervals were 16.09±5.7 hours in the sequential group and 8.06±4.2 hours in the simultaneous group (P<.001). Cesarean delivery rate, composite neonatal outcomes, and chorioamnionitis were not different between the 2 groups.

CONCLUSION

In nulliparous pregnant women, induction of labor using the simultaneous approach did not shorten the oxytocin initiation to delivery interval compared with the sequential approach. Moreover, both approaches showed no difference in the rates of adverse maternal and neonatal outcomes.

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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Outpatient Cervical Ripening With Misoprostol in Low-Risk Pregnancies

Objective To determine if outpatient cervical ripening with daily misoprostol can reduce admission to delivery time in women with low-risk pregnancies at 39 or more weeks of gestation. Study design This is a retrospective cohort study of a convenience sample of low-risk pregnancies that underwent elective outpatient cervical ripening compared to matched controls for parity (nulliparous vs. parous) and gestational age. Time from admission to delivery, induction agents, presence of tachysystole, mode of delivery, length of hospitalization, neonatal intensive care unit (NICU) admission, and low Apgar scores were compared. Results Fifty-six patients who underwent outpatient cervical ripening with daily dosing of misoprostol were compared to 56 patients matched for parity and gestational weeks who underwent inpatient cervical ripening/induction of labor with misoprostol. We found the time from admission to delivery in the outpatient cervical ripening cohort was significantly lesser than the inpatient cohort (17.5 ± 11.5 hours outpatient vs. 26.6 ± 15.6 hours inpatient, P=0.001). More patients (N=18, 32%) were able to deliver within 12 hours of admission in the outpatient induction group compared to the inpatient group (N=8, 11%, P=0.010). There were no differences in frequency of cesarean delivery, uterine tachysystole with or without fetal heart rate changes, NICU admission, low Apgar scores, or low umbilical artery pH values between the two groups. Conclusion Outpatient cervical ripening with misoprostol may be a feasible alternative to inpatient cervical ripening in low-risk pregnancies, may help improve patient experience, and reduce the operational burden that elective induction confers upon labor and delivery units.

Outpatient vs inpatient Foley catheter induction of labor in multiparas with unripe cervixes: A randomized trial

INTRODUCTION

Multiparous labor inductions are typically successful, and the process can be rapid, starting from a ripened cervix with a predictable response to amniotomy and oxytocin infusion. Outpatient Foley catheter labor induction in multiparas with unripe cervixes is a feasible option as the mechanical process of ripening is usually without significant uterine contractions and well tolerated. Labor contractions can be initiated by amniotomy and titrated oxytocin infusion in the hospital for well-timed births during working hours as night birth are associated with adverse events. We sought to evaluate outpatient compared with inpatient Foley catheter induction of labor in multiparas for births during working hours and maternal satisfaction.

MATERIAL AND METHODS

A randomized trial was conducted in the University of Malaya Medical Center. A total of 163 term multiparas (no dropouts) with unripe cervixes (Bishop score ≤5) scheduled for labor induction were randomized to outpatient or inpatient Foley catheter. Primary outcomes were delivery during "working hours" 08:00-18:00 h and maternal satisfaction on allocated care (assessed by 11-point visual numerical rating score 0-10, with higher score indicating more satisfied).

CLINICAL TRIAL REGISTRATION

ISRCTN13534944.

RESULTS

Comparing outpatient and inpatient arms, delivery during working hours were 54/82 (65.9%) vs. 48/81 (59.3%) (relative risk 1.1, 95% CI 0.9-1.4, p = 0.421) and median maternal satisfaction visual numerical rating score was 9 (interquartile range 9-9) vs. 9 (interquartile range 8-9, p = 0.134), repectively. Duration of hospital stay and membrane rupture to delivery interval were significantly shorter in the outpatient arm: 35.8 ± 20.2 vs. 45.2 ± 16.2 h (p = 0.001) and 4.1 ± 2.9 vs. 5.3 ± 3.6 h (p = 0.020), respectively. Other maternal and neonatal secondary outcomes were not significantly different.

CONCLUSIONS

The trial failed to demonstrate the anticipated increase in births during working hours with outpatient compared with inpatient induction of labor with Foley catheter in parous women with an unripe cervix. Hospital stay and membrane rupture to delivery interval were significantly shortened in the outpatient group. The rate of maternal satisfaction was high in both groups and no significant differences were found.

Maternal and Neonatal Outcomes in Nulliparous Participants Undergoing Labor Induction by Cervical Ripening Method

OBJECTIVE

 This study aimed to evaluate maternal and neonatal outcomes by method of cervical ripening for labor induction among low-risk nulliparous individuals.

STUDY DESIGN

 This is a secondary analysis of a multicenter randomized trial of labor induction at 39 weeks versus expectant management in low-risk nulliparous participants. Participants undergoing cervical ripening for labor induction in either group were included. Participants were excluded for preripening membrane rupture, abruption, chorioamnionitis, fetal demise, or cervical dilation ≥3.5 cm. Cervical ripening was defined by the initial method used: prostaglandin only (PGE; referent), Foley with concurrent prostaglandin (Foley-PGE), Foley only (Foley), and Foley with concurrent oxytocin (Foley-oxytocin). Coprimary outcomes were adverse maternal and neonatal composites. Secondary outcomes included cesarean delivery and length of labor and delivery (L&D) stay. Multivariable analysis was used to adjust for patient characteristics.

RESULTS

 Of 6,106 participants included in the trial, 2,376 (38.9%) met criteria for this analysis. Of these, 1,247 (52.4%) had cervical ripening with PGE, 290 (12.2%) had Foley-PGE, 385 (16.2%) had Foley, and 454 (19.1%) had Foley-oxytocin. The maternal composite outcome was similar among participants who received Foley-PGE (24.1%, adjusted relative risk [aRR] = 1.21, 95% confidence interval [CI]: 0.96-1.52), Foley (21.3%, aRR = 1.16, 95% CI: 0.92-1.45), or Foley-oxytocin (19.4%, aRR = 1.04, 95% CI: 0.83-1.29), compared with PGE (19.7%). The neonatal composite outcome was less frequent in participants who received the Foley-PGE (2.4%, aRR = 0.35, 95% CI: 0.16-0.75) or Foley (3.6%, aRR = 0.51, 95% CI: 0.29-0.89) but did not reach statistical significance for participants who received Foley-oxytocin (4.6%, aRR = 0.63, 95% CI: 0.40-1.01) compared with PGE only (6.8%). Participants who received Foley-PGE or Foley-oxytocin had a shorter L&D stay (adjusted mean difference = -1.97 hours, 95% CI: -3.45 to -0.49 and -5.92 hours, 95% CI: -7.07 to -4.77, respectively), compared with PGE.

CONCLUSION

 In term low-risk nulliparous participants, Foley alone or concurrent with PGE is associated with a lower risk of adverse neonatal outcomes than with PGE alone. Length of L&D stay was the shortest with concurrent Foley-oxytocin.

KEY POINTS

· Adverse maternal outcomes are similar among different methods of cervical ripening in low-risk women.. · Adverse neonatal outcomes are less frequent with use of Foley alone or in combination with PGE.. · The use of Foley alone, or in combination with other agents, appears to be beneficial..

Comparing Foley Catheter to Prostaglandins for Cervical Ripening in Multiparous Women

OBJECTIVE

This study sought to test the hypothesis that among multiparous women requiring cervical ripening, mechanical ripening with a Foley catheter is more effective than prostaglandin preparations.

METHODS

This was a retrospective analysis of multiparous women with a singleton gestation who required cervical ripening in a single tertiary center from 2014 to 2019. Women who underwent cervical ripening with a Foley catheter (Foley group) were compared with women who underwent cervical ripening using a controlled-release dinoprostone vaginal insert (PGE₂-CR group) or dinoprostone vaginal gel (PGE₂-gel group). The primary outcome was the ripening-to-delivery interval.

RESULTS

A total of 229 women met the study criteria (Foley group: 95; PGE₂-CR group: 83; PGE₂-gel group: 51). Women in the Foley group had a significantly shorter ripening-to-delivery interval compared with women in the PGE₂-CR group (16.2 ± 9.2 hours vs. 27.0 ± 14.8 hours; P < 0.001) and were more likely to deliver within 12 hours (47.4% vs. 12.0%; P < 0.001; adjusted relative risk [aRR] 3.87; 95% confidence interval [CI] 2.07-7.26) and within 24 hours (78.9% vs. 49.4%; P < 0.001; aRR 1.61; 95% CI 1.26-2.06). Women in the Foley group were also less likely to require a second ripening method compared with women in the PGE₂-CR group (1.1% vs. 8.4%; P = 0.018; aRR 7.26; 95% CI 2.99-17.62). These differences were not observed when comparing the Foley and the PGE₂-gel groups. The cesarean section rate was similar among the Foley group (9.5%), PGE₂-CR group (9.6%; P = 0.970), and PGE₂-gel group (11.8%; P = 0.664).

CONCLUSION

In multiparous women requiring cervical ripening, all methods of cervical ripening have a similar success rate. However, the use of a PGE₂-CR insert is associated with a considerably longer interval to delivery compared with a Foley catheter or PGE₂ gel.

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.

Foley catheter versus cervical double balloon for labor induction: a prospective randomized study

OBJECTIVE

Cervical ripening by mechanical methods enhances labor induction success. We compared Cervical Ripening Double Balloon catheter (CRDB) to Foley catheter.

STUDY DESIGN

This prospective blind study randomized 85 nulliparas and 95 multiparas to labor induction by either Foley catheter or CRDB. Primary outcomes were Bishop score increment, time from catheter withdrawal to delivery, and cesarean section rate.

RESULTS

In multiparas, mean Bishop score increment between pre- and post-catheter was significantly higher in the CRDB catheter than in the Foley group (4.4 ± 1.9 and 3.4 ± 2.0, respectively, p = .02). Mean interval from catheter withdrawal to delivery was shorter in the CRDB catheter (14.6 ± 12.3 and 8.6 ± 5.4) than in the Foley catheter group (22.6 ± 27.2 and 13.9 ± 17.7), in both nulliparas and multiparas (p = .05 and p = .03, respectively). In nulliparas, no statistically significant differences were found in mean Bishop score increment between the two catheters, but cesarean section rate was higher in the Foley group than the CRDB group (46.5% and 20%, respectively, p = .02).

CONCLUSION

Bishop score increment by CRDB catheter is more effective than induction by Foley catheter in multiparas. CRDB catheter is associated with decreased time to delivery in both nulliparas and multiparas and a lower cesarean section rate in nulliparas. ClinicalTrials.gov Identifier: NCT00501033.

Efficacy of second-trimester termination procedure; medical, mechanic, or combine?

Objectives

During mid-trimester, it is necessary to terminate pregnancy due to some fetal anomalies and intrauterine death. Therefore, in this study, we aimed to compare abortion induction methods and combined use retrospectively.

Methods

About 112 out of 223 pregnant patients were included in the study. The groups were determined as follows: Group 1 including pregnant patients who were administered misoprostol only (50 patients), Group 2 including pregnant patients who were administered single dose misoprostol (according to FIGO) and subsequently received cervical Foley catheter (30 patients), and Group 3 including pregnant patients who received Foley catheter only (32 patients). These three groups were compared in terms of effectiveness of the method, side effects, and complications as well as their characteristics.

Results

In terms of characteristic of the groups, the average age of the women in the Group 1 was significantly higher than other two groups (p < 0.001). In terms of effectiveness of the method, the termination period in Groups 1 and 2 was significantly lower than Group 3 (p < 0.001). However, in terms of complications, it was observed that uterine rupture was developed in Group 1.

Conclusions

Although medical methods may seem to be more effective in the process of termination, mechanical methods seem more reliable in terms of reliability. Especially combined methods can be used to increase effectiveness and also to reduce complications.

Foley catheter with simultaneous oxytocin on labor induction: a meta-analysis of randomized controlled trials

Objective: It is unclear that whether Foley catheter with simultaneous oxytocin could improve the efficacy of induction outcome. Method: To conduct a meta-analysis of randomized controlled trial (RCT) studies to evaluate the effect of Foley catheter with simultaneous oxytocin on labor induction. PubMed, Embase, and other databases were searched from their inception to July 2017. We included all RCTs comparing Foley catheter with simultaneous oxytocin (i.e. intervention group) with Foley catheter followed by oxytocin (i.e. control group) in the three kinds of women (nulliparas and multiparas/only nulliparas/only multiparas). We estimate summarized relative risk (RR) and 95% confidence intervals (CIs) for dichotomous outcomes, standard mean difference for continuous outcomes. Fixed- and random-effects models were used, depending on heterogeneity. Results: After application of our inclusion and exclusion criteria, six RCTs with a total of 1133 participants were identified. We found that only nulliparas had significant RR of delivery within 24 h (RR = 1.32, 95% CI: 1.12, 1.55, I² = 46.5%). Meanwhile, there was no statistically significant difference between intervention and control groups in vaginal delivery in 24 h, cesarean delivery, time to delivery, and Apgar score at 5 min less than 7. Foley catheter with simultaneous oxytocin did not increase the risk of side effects, included chorioamnionitis, postpartum hemorrhage, uterine hyperstimulation, and neonatal intensive care unit admission. Conclusion: The results seem to support the use of oxytocin to a Foley catheter at the initiation of labor induction, as it might lead to increases the rate of delivery within 24 h in nulliparas.

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.

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%.

Tension compared to no tension on a Foley transcervical catheter for cervical ripening: a randomized controlled trial

BACKGROUND

Cervical ripening of an unfavorable cervix can be achieved by placement of a transcervical catheter. Advantages of this method include both lower cost and lower risk of tachysystole than other methods. Despite widespread use with varying degrees of applied tension, an unanswered question is whether there is an advantage to placing the transcervical catheter to tension compared with placement without tension.

OBJECTIVE

The purpose of this study was to determine whether tension placed on a transcervical balloon catheter that is inserted for cervical ripening results in a faster time to delivery.

STUDY DESIGN

This was a prospective, randomized controlled trial; 140 women who underwent cervical ripening (Bishop score, ≤6) were assigned randomly to a balloon catheter with applied tension vs no tension. Tension was created when the catheter was taped to the patient's thigh and tension was reapplied in 30-minute increments. There were 67 patients in the tension group and 73 patients in the no tension group. Low-dose oxytocin (maximum, 6 mU/min) was administered after catheter placement. The primary outcome was time from catheter insertion to delivery. A secondary outcome was time from insertion to catheter expulsion. The Kolmogorov-Smirnov test was used to determine whether the data were distributed normally. Survival curves that used lifetables were constructed from time of catheter insertion to delivery and from time of catheter insertion to catheter expulsion and were compared with the use of the Wilcoxon (Gehan) Breslow statistic. A probability value of <.05 was set to denote statistical significance.

RESULTS

Baseline characteristics were similar between groups. The median time from catheter insertion to delivery was not significantly different between the tension group and the no tension group (16.2 vs 16.9 hours; P=.814). The median time from catheter insertion to expulsion, however, was significantly less in the tension group vs the no tension group (2.6 vs 4.6 hours; P<.001), respectively. Vaginal delivery within 24 hours was not significantly different between the tension and no tension groups (41/52 [79%] vs 37/52 [71%]; P=.365) nor were there significant differences in cesarean delivery rates between the tension and no tension groups (17/67 [25%] vs 27/73 [37%]; P=.139).

CONCLUSION

Application of tension did not result in faster delivery times but did result in faster times to catheter expulsion.

Timing of sequential use of double-balloon catheter and oral misoprostol for induction of labor

AIM

The best time to commence cervical ripening with a balloon catheter is unknown. The aim of this study was to evaluate whether application of a balloon catheter in the morning or in the evening is better when sequential prostaglandin application is planned.

METHODS

This multicenter historical cohort study included 415 women with an unfavorable cervix undergoing labor induction at term. Labor was induced with a double-balloon catheter and the sequential use of oral misoprostol if necessary. The balloon catheter was placed in the morning group between 02:00-15:00 and in the evening group between 15:00-02:00. The primary outcome measure was the cesarean section rate. Secondary outcome measures included failed labor induction (no vaginal delivery within 72 h).

RESULTS

The cesarean section rate did not differ between the groups (morning 26.9%, evening 24.3%; P = 0.5553); however, more women in the morning group did not deliver within 72 h (8.8% vs 3.1%; P = 0.0138). In nulliparous women, labor induction failed more often in the morning group (12% vs. 4%, P = 0.043). In parous women, the induction-to-delivery interval was longer in the morning group (1756 vs. 1349 min; P = 0.046), and there were fewer deliveries within 24 h (35% vs. 56%, P = 0.016).

CONCLUSIONS

When sequential use of a double-balloon catheter and oral misoprostol for labor induction is planned, the preferable time for catheter placement is in the evening. This resulted in fewer failed inductions in nulliparous women and a shorter induction-to-delivery interval and more deliveries within 24 h in parous women.

Induction of labor--pharmacology methods

Pharmacologic methods for induction of labor have been used for many decades. Pharmacologic agents have an advantage over mechanical methods in that they can be used during both the initial cervical ripening stage of induction and throughout the second stage of labor. Pharmacologic induction agents such as prostaglandins and oxytocin are commonly used for labor and delivery floors and are well established for use in cervical ripening. Nitric oxide donors and mifepristone are known agents in medicine but are new and actively studied in the area of cervical ripening. These agents are introduced and analyzed in this review.

Inner thigh taping vs traction for cervical ripening with a Foley catheter: a randomized controlled trial

OBJECTIVE

To assess the effectiveness of inner thigh "Taping" compared with "Traction" using a weighted bag when an intracervical Foley catheter is used for cervical ripening.

STUDY DESIGN

We performed a randomized controlled trial at a tertiary hospital on women with a singleton pregnancy in cephalic presentation admitted for labor induction with a Bishop score ≤6. A 30 mL intracervical Foley catheter was placed for ripening. Women were randomly allocated to inner thigh Taping or to Traction with a 500 mL weighted bag of fluid. The primary outcome was time to delivery. Secondary outcomes were time to expulsion of the catheter, maternal discomfort (visual analog scale), mode of delivery, and maternal morbidities.

RESULTS

We randomized 197 women. After exclusions (4 ineligible, 2 withdrawn by provider), we analyzed 191 (96 Taping, 95 Traction) women in their assigned groups. Groups were similar regarding maternal race, age, parity, gestational age, and induction indication. Time to delivery was not significantly different (mean ± standard deviation: 19.8 ± 8.5 vs 18.8 ± 8.0 hours; P = .39). Time to catheter expulsion was shorter in the Traction Group (median, 2.6; range, 0.2-10.8 vs median, 1.5; range, 0.1-6.3 hours; P < .001). Change in Bishop and pain scores, cesarean delivery rates, clinical amnionitis, and other maternal morbidities were similar between groups. Subset analyses of those with vaginal delivery and among nulliparas, and multiparas revealed similar results.

CONCLUSION

Traction on the intracervical Foley catheter during cervical ripening shortens the time to spontaneous catheter expulsion without affecting the time to delivery.

Labor induction by transcervical balloon catheter and cerebral palsy associated with umbilical cord prolapse

AIM

The aim of this study was to determine whether the use of transcervical balloon catheter (TCBC) for induction of labor (IOL) is a risk factor for cerebral palsy (CP) associated with umbilical cord prolapse (UCP-CP) in singleton pregnancies with cephalic presentation.

MATERIAL AND METHODS

Among all 102 infants with CP who were preliminarily determined as caused by antenatal and/or intrapartum hypoxemia by the Japan Council for Quality Health Care until April 2012, all 56 infants who met all of the following criteria were studied: cephalic singleton pregnancy, reassuring fetal status on electronic cardiotocogram at time of admission to obstetric facilities for labor pains, ruptured fetal membranes, and/or IOL, and hypoxic-ischemic encephalopathy at birth. Clinical backgrounds were compared between six infants with UCP-CP and the remaining 50 infants with CP not associated with UCP (non-UCP-CP).

RESULTS

Frequencies of IOL (83% [5/6] vs 32% [16/50], P = 0.0236), use of TCBC (67% [4/6] vs 10% [5/50], P = 0.0044), and amniotomy (67% [4/6] vs 24% [12/50], P = 0.0494) were significantly higher in the UCP-CP than the non-UCP-CP group. Only TCBC was a risk factor significantly associated with UCP-CP after logistic regression analysis, yielding an odds ratio of 18.0 (95% confidence interval, 2.6-124; P = 0.003). Saline volumes of 80-150 mL were used for TCBC inflation in the four UCP-CP patients.

CONCLUSION

Use of TCBC with a saline volume ≥ 80 mL was a significant risk factor for UCP-CP; however, the absolute risk of UCP-CP was estimated to be very low, approximately one in 7875 TCBC users.

Current pharmacotherapy options for labor induction

INTRODUCTION

Labor induction is now reported to occur in up to 30 - 40% of obstetrical patients. There are a number of pharmacological options available to facilitate labor induction, including oxytocin and analogues of prostaglandins E1 and E2, which have particular utility when labor induction necessitates cervical ripening, as when labor induction occurs in the context of an unfavorable cervix.

AREAS COVERED

This paper reviews acceptable pharmacological options for labor induction, especially when cervical ripening is required. These options include oxytocin and a number of prostaglandin formulations using dinoprostone and misoprostol. It also covers several analyses of published clinical trials (Phase-III) describing evidence of effectiveness.

EXPERT OPINION

Oxytocin is best used when labor needs to be induced in the context of a favorable cervix. When the cervix is not favorable, cervical ripening using prostaglandins should precede labor induction. Either dinoprostone or misoprostol are superior to oxytocin alone for cervical ripening. However, judicious, careful considerations need to be made at the outset of labor induction so as to balance maternal and fetal risks, and these should be guided by institutional policies that reflect the evidence-base.

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 simplicity of preservation, lower cost and reduction of the side effects.

OBJECTIVES

To determine the effects of mechanical methods for third trimester cervical ripening or induction of labour in comparison with placebo/no treatment, prostaglandins (vaginal and intracervical prostaglandin E2 (PGE2), misoprostol) and oxytocin.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2011) and bibliographies of relevant papers. We updated this search on 16 January 2012 and added the 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 methods listed above it on a predefined list of methods of labour. A comparison with amniotomy will be added, should this comparison be made in future trials.Different types of intervention have been considered as mechanical methods: (1) introduction of laminaria tents, or their synthetic equivalent (Dilapan), into the cervical canal; (2) the introduction of a catheter through the cervix into the extra-amniotic space, with or without traction; (3) use of a catheter to inject fluidsin the extra-amniotic spaceIn addition, we made other comparisons: (1) specific mechanical methods (balloon catheter and laminaria tents) compared with any prostaglandins or with oxytocin; (2) addition of prostaglandins or oxytocin to mechanical methods compared with prostaglandins alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed risk of bias. Two review authors independently extracted data.

MAIN RESULTS

For this update we have included a further 27 studies. The review includes 71 randomised controlled trials (total of 9722 women), ranging from 39 to 588 women per study. Most studies reported on caesarean section, all other outcomes are based on substantially fewer women. Four additional studies are ongoing.Mechanical methods versus no treatment: one study (48 woman) reported on women who did not achieve vaginal delivery within 24 hours (risk ratio (RR) 0.90; 95% confidence interval (CI) 0.64 to 1.26). The risk of caesarean section was similar between groups (six studies; 416 women, RR 1.00; 95% CI 0.76 to 1.30). There were no cases of severe neonatal and maternal morbidity.Mechanical methods versus vaginal PGE2 (17 studies;1894 woman): The proportion of women who did not achieve vaginal delivery within 24 hours was not significantly different (three studies; 586 women RR 1.72; 95% CI 0.90 to 3.27); however, for the subgroup of multiparous women the risk of not achieving delivery within 24 hours was higher (one study; 147 women RR 4.38, 95% CI 1.74 to 10.98), with no increase in caesarean sections (RR 1.19, 95% CI 0.62-2.29). Compared with intracervical PGE2 (14 studies;1784 women and misoprostol there was no significant difference in the proportion of women not achieving vaginal delivery within 24 hours.Mechanical methods reduced the risk of hyperstimulation with fetal heart rate changes when compared with vaginal prostaglandins: vaginal PGE2 (eight studies; 1203 women, RR 0.16; 95% CI 0.06 to 0.39) and misoprostol (3% versus 9%) (nine studies; 1615 women, RR 0.37; 95% CI 0.25 to 0.54). Risk of caesarean section between mechanical methods and prostaglandins was comparable. Serious neonatal and maternal morbidity were infrequently reported and did not differ between the groups.Mechanical methods compared with induction with oxytocin (reduced the risk of caesarean section (five studies; 398 women, RR 0.62; 95% CI 0.42 to 0.90). The likelihood of vaginal delivery within 24 hours was not reported. Hyperstimulation with fetal heart rate changes was reported in one study (200 participants), and did not differ. There were no reported cases of severe maternal or neonatal morbidity.

AUTHORS' CONCLUSIONS

Induction of labour using mechanical methods results in similar caesarean section rates as prostaglandins, for a lower risk of hyperstimulation. Mechanical methods do not increase the overall number of women not delivered within 24 hours, however the proportion of multiparous women who did not achieve vaginal delivery within 24 hours was higher when compared with vaginal PGE2. Compared with oxytocin, mechanical methods reduce the risk of caesarean section.

Foley catheter versus vaginal prostaglandin E2 gel for induction of labour at term (PROBAAT trial): an open-label, randomised controlled trial

BACKGROUND

Induction of labour is a common obstetric procedure. Both mechanical (eg, Foley catheters) and pharmacological methods (eg, prostaglandins) are used for induction of labour in women with an unfavourable cervix. We aimed to compare the effectiveness and safety of induction of labour with a Foley catheter with induction with vaginal prostaglandin E2 gel.

METHODS

We did an open-label, randomised controlled trial in 12 hospitals in the Netherlands between Feb 10, 2009, and May 17, 2010. We enrolled women with a term singleton pregnancy in cephalic presentation, intact membranes, an unfavourable cervix, an indication for induction of labour, and no prior caesarean section. Participants were randomly allocated by an online randomisation system to induction of labour with a 30 mL Foley catheter or vaginal prostaglandin E2 gel (1:1 ratio). Because of the nature of the intervention this study was not blinded. The primary outcome was caesarean section rate. Secondary outcomes were maternal and neonatal morbidity and time from intervention to birth. All analyses were done on an intention-to-treat basis. We also did a meta-analysis that included our trial. The trial was registered with the Dutch trial registry, number NTR 1646.

FINDINGS

824 women were allocated to induction of labour with a Foley catheter (n=412) or vaginal prostaglandin E2 gel (n=412). Caesarean section rates were much the same between the two groups (23%vs 20%, risk ratio [RR] 1·13, 95% CI 0·87-1·47). A meta-analysis including our trial data confirmed that a Foley catheter did not reduce caesarean section rates. We recorded two serious maternal adverse events, both in the prostaglandin group: one uterine perforation and one uterine rupture.

INTERPRETATION

In women with an unfavourable cervix at term, induction of labour with a Foley catheter is similar to induction of labour with prostaglandin E2 gel, with fewer maternal and neonatal side-effects.

FUNDING

None.

Comparative Study of Intra-cervical Foley's Catheter and PGE(2) Gel for Pre-induction Ripening (Cervical)

AIM

The success of induction of labor depends on the cervical status at the time of induction.

OBJECTIVE

For effective cervical ripening both Foley's catheter and PGE(2) gel are used. The aim of this study was to compare the efficacy of intra cervical Foley's catheter and intra cervical PGE(2) gel in cervical ripening for the successful induction of labor.

STUDY DESIGN

A randomized, prospective study was conducted in the Dept of OBGY, GMCH, Aurangabad from July 2005-January 2008. 400 patients at term with a Bishop's score ≤3 with various indications for induction were randomly allocated to receive (200 pts) intra-cervical Foley's catheter or PGE(2) gel (200 pts). After 6 h post induction, Bishop's score was noted labor was augmented if required. Statistical analysis was done using Chi square test and t test.

RESULT

The groups were comparable with respect to maternal age, gestation age, indication of induction and initial Bishop's score. Both the groups showed significant change in the Bishop's score, 5.56 ± 1.89 and 5.49 ± 1.82 for Foley's catheter and PGE(2) gel, respectively, P < 0.001; However there was no significant difference between the two groups. There was no significant difference in the side effects. Twenty eight cesarean sections (14%) were performed in Group A and 37 (18.5%) were performed in Group B (not significant). The induction to delivery interval was 15.32 ± 5.24 h in Group A and 14.2 ± 5.14 h in Group B (P = 0.291). Apgar scores, birth weights and NICU admissions showed no difference between the two groups.

CONCLUSION

This study shows that both Foley's Catheter and PGE(2) gel are equally effective in pre induction cervical ripening.

Foley catheter balloon vs locally applied prostaglandins for cervical ripening and labor induction: a systematic review and metaanalysis

We performed a metaanalysis of publications comparing the efficacy and safety of cervical ripening and labor induction by Foley catheter balloon (FCB) vs locally applied prostaglandins (LAPG) in the third trimester of pregnancy. Twenty-seven randomized controlled trials (1966-2008; 3532 participants) were selected from MEDLINE, EMBASE, and CENTRAL searches. There was no significant difference between FCB and LAPG in cesarean delivery rates. LAPG had a significantly increased risk of excessive uterine activity (P = .001). FCB had a significantly higher risk of oxytocin induction/augmentation during labor (P = .0002). Cervical prostaglandin-E2 was less effective (P = .04), and vaginal prostaglandin-E1 bore a significantly higher risk of excessive uterine activity (P < .0001) and meconium staining (P = .04). We concluded that FCB and LAPG result in similar cesarean delivery rates, that FCB bears a higher risk of oxytocin use for labor induction and/or augmentation, and that LAPG carries a higher risk of contraction abnormalities.

Reducing stillbirths: interventions during labour

BACKGROUND

Approximately one million stillbirths occur annually during labour; most of these stillbirths occur in low and middle-income countries and are associated with absent, inadequate, or delayed obstetric care. The low proportion of intrapartum stillbirths in high-income countries suggests that intrapartum stillbirths are largely preventable with quality intrapartum care, including prompt recognition and management of intrapartum complications. The evidence for impact of intrapartum interventions on stillbirth and perinatal mortality outcomes has not yet been systematically examined.

METHODS

We undertook a systematic review of the published literature, searching PubMed and the Cochrane Library, of trials and reviews (N = 230) that reported stillbirth or perinatal mortality outcomes for eight interventions delivered during labour. Where eligible randomised controlled trials had been published after the most recent Cochrane review on any given intervention, we incorporated these new trial findings into a new meta-analysis with the Cochrane included studies.

RESULTS

We found a paucity of studies reporting statistically significant evidence of impact on perinatal mortality, especially on stillbirths. Available evidence suggests that operative delivery, especially Caesarean section, contributes to decreased stillbirth rates. Induction of labour rather than expectant management in post-term pregnancies showed strong evidence of impact, though there was not enough evidence to suggest superior safety for the fetus of any given drug or drugs for induction of labour. Planned Caesarean section for term breech presentation has been shown in a large randomised trial to reduce stillbirths, but the feasibility and consequences of implementing this intervention routinely in low-/middle-income countries add caveats to recommending its use. Magnesium sulphate for pre-eclampsia and eclampsia is effective in preventing eclamptic seizures, but studies have not demonstrated impact on perinatal mortality. There was limited evidence of impact for maternal hyperoxygenation, and concerns remain about maternal safety. Transcervical amnioinfusion for meconium staining appears promising for low/middle income-country application according to the findings of many small studies, but a large randomised trial of the intervention had no significant impact on perinatal mortality, suggesting that further studies are needed.

CONCLUSION

Although the global appeal to prioritise access to emergency obstetric care, especially vacuum extraction and Caesarean section, rests largely on observational and population-based data, these interventions are clearly life-saving in many cases of fetal compromise. Safe, comprehensive essential and emergency obstetric care is particularly needed, and can make the greatest impact on stillbirth rates, in low-resource settings. Other advanced interventions such as amnioinfusion and hyperoxygenation may reduce perinatal mortality, but concerns about safety and effectiveness require further study before they can be routinely included in programs.

A randomised controlled trial of intravaginal dinoprostone, intravaginal misoprostol and transcervical balloon catheter for labour induction

OBJECTIVE

To compare the efficacy and safety of induction of labour by vaginal application of dinoprostone or misoprostol or transcervical insertion of a balloon (Bard) catheter.

DESIGN

A non-blinded, randomised, controlled trial.

SETTING

A tertiary level Swedish hospital.

POPULATION

A total of 592 women who had undergone full-term pregnancies, not previously been subjected to a caesarean section, and required induction of labour for common, routine indications.

METHODS

Women were randomly assigned to induction of labour using intravaginal dinoprostone (2 mg once every 6 hours) or misoprostol (25 micrograms once every 4 hours) or a transcervical balloon catheter.

MAIN OUTCOME MEASURES

The time interval between induction to delivery in general and vaginal delivery in particular, the mode of delivery, maternal and neonatal parameters of outcome.

RESULTS

Of the 588 subjects included in the final intention-to-treat analysis, 191 were assigned to treatment with dinoprostone, 199 with misoprostol and 198 with the balloon catheter. The shortest mean induction-to-delivery interval was obtained with the catheter (12.9 hours versus 16.8 and 17.3 hours for dinoprostone and misoprostol, respectively). The efficacies of the two prostaglandins were similar. The maternal and neonatal outcomes associated with each of the three procedures were similar.

CONCLUSIONS

Induction of labour with a transcervical balloon catheter is effective and safe and can be recommended as the first choice. The two prostaglandins, dinoprostone and misoprostol, were shown to be equally effective and safe, while misoprostol costs significantly less and is easier to store.

Do mechanical methods of cervical ripening increase infectious morbidity? A systematic review

The purpose of this study was to review systematically randomized controlled trials that were associated with cervical ripening. We identified randomized controlled trials that compared the use of Foley catheter, with or without extraamniotic saline solution infusion, Laminaria, or hygroscopic dilators for cervical ripening or induction with pharmacologic agents or placebo. Randomized controlled trials that evaluated maternal or neonatal infection were selected. The outcomes that were assessed were maternal and neonatal infection, chorioamnionitis, and endomyometritis. Thirty studies met inclusion criteria. Compared with the use of pharmacologic methods alone, patients who underwent cervical ripening with mechanical agents had a significantly higher rate of maternal infection rates. Similar results were noted for patients who underwent ripening with Foley catheter alone in comparison with pharmacologic agents. No difference was noted in maternal infection rates for patients who underwent ripening with extraamniotic saline solution infusion, Laminaria, or hygroscopic dilators. Compared with the use of pharmacologic agents alone, maternal and neonatal infectious morbidity appears to be increased when mechanical agents are used for cervical ripening.

The views of obstetricians in the south-west of England on the use of prostaglandins and syntocinon in VBAC

The aim of our study was to explore the views of consultant obstetricians in the south-west of England on the use of prostaglandin and oxytocin in women undergoing vaginal birth after caesarean delivery (VBAC), and assess how the perceived risk of uterine rupture in such a cohort of women affected their practice. A postal questionnaire was sent to randomly selected consultant obstetricians in the south-west of England. The response rate from the survey was 59.2%. The study showed that the willingness of consultants to use prostaglandin in VBAC was related to their length of practice. Some 89.7% of all respondents claim they would use syntocinon for augmentation in VBAC; 75% of all the responding consultants who have been in the post for longer than 10 years claim they would not use either of the agents in VBAC. We conclude that, despite concerns about the risks of increased uterine rupture in both induction and augmentation in labour of women undergoing VBAC, our study did not seem to support the fact that obstetricians' practices are influenced by this perceived risk.

Nitric oxide donor isosorbide mononitrate for pre-induction cervical ripening at 41 weeks' gestation: A randomized controlled trial

OBJECTIVE

Nitric oxide donors have been shown to cause cervical ripening. The aim of this study was to determine whether sustained release isosorbide mononitrate (ISMN-SR) 60 mg administered vaginally is effective for pre induction cervical ripening at 41 weeks' gestation.

METHODS

A double-blind randomised controlled trial was carried out at the University Obstetric Unit, Galle, Sri Lanka for a period of 9 months, commencing 1st August 2003. One hundred and fifty-six consecutive women with uncomplicated singleton pregnancies at 41 weeks' gestation with a modified Bishop Score <5 were allocated by stratified (primip/multip) block randomization to receive either ISMN-SR 60 mg (n = 78) or vitamin C 100 mg (n = 78) vaginally. Modified Bishop Score at 41 weeks + 2 days' gestation and the proportions establishing spontaneous labor or becoming favorable for induction of labor (IOL) by 41 weeks + 2 days' gestation were evaluated in each group.

RESULTS

At the commencement of the study there were no differences between the mean age, parity or modified Bishop Score of the two groups. In the ISMN-SR group, there was a marked increase in the proportion establishing spontaneous labor (28% vs 7.5%, P < 0.01) and being favorable for IOL (40% vs 9% P < 0.001), 2 days after therapy. In the ISMN-SR group, there was a significantly higher increase in the mean modified Bishop Score (3.8, 95% CI 2.3-5.3 vs 1.3, 95% CI 0.3-2.2, P < 0.01) and a marked decrease in the proportion of subjects requiring further ripening of the cervix with a Foley catheter. (32% vs 79%, P < 0.001). The cesarean section rates were similar in both groups.

CONCLUSION

Sustained release ISMN administered vaginally is effective for preinduction cervical ripening.

Cervical ripening with the Foley catheter

OBJECTIVE

To evaluate maternal and neonatal outcomes in a large series of patients undergoing cervical ripening with a Foley catheter.

METHODS

The database of the Labor and Delivery Unit of the University of a teaching hospital in Italy was used to identify consecutive patients with a Bishop score (BS) of 4 or less who underwent pre-induction cervical ripening with a Foley catheter. The main outcome measures were clinical chorioamnionitis, endometritis, and suspected and culture-proven neonatal sepsis.

RESULTS

Of 602 women undergoing cervical ripening with a Foley catheter, 160 (26.6%) went into active labor without additional interventions. Oxytocin was administered immediately after removal of the Foley catheter in 188 (31.2%) of the women, and 254 (42.2%) required an application of prostaglandin E2 vaginal gel. The cesarean delivery rate was 25.6%. The median time to delivery was 1469 min (range, 94-3350 min). Of the women who gave birth vaginally, 225 (50.2%) were delivered within 24 h. Clinical chorioamnionitis and postpartum endometritis occurred in 3 (0.5%) and 6 (1.0%) of the women, respectively. Neonatal sepsis was suspected in 4 (0.7%) of the newborns but blood culture results were negative in all cases.

CONCLUSION

Transcervical use of the Foley catheter is safe for pre-induction cervical ripening, and the associated risk of maternal or perinatal infections is negligible.

Cervical ripening with a Foley catheter: the role of pre- and postripening ultrasound examination of the cervix

OBJECTIVE

The objective of the study was to assess sonographic changes in cervical length and posterior cervical angle in women undergoing cervical ripening with an extraamniotic Foley catheter and to determine whether pre- and postripening ultrasound parameters could help predict successful cervical ripening and the outcome of labor induction.

STUDY DESIGN

Cervical length and posterior cervical angle were measured by transvaginal sonography in 155 women with a Bishop score of 4 or less before placement of a transcervical Foley catheter for cervical ripening. At the time of Foley removal, women who did not enter active labor underwent a second ultrasound assessment of the cervix. Outcome measures were successful ripening, vaginal delivery, vaginal delivery within 24 hours, and vaginal delivery achieved with the Foley only. Multiple logistic regression models were generated to identify pre- and postripening clinical and ultrasound parameters independently associated with successful induction.

RESULTS

Forty patients (25.8%) went into active labor after spontaneous expulsion or removal of the Foley, without any additional intervention. A successful cervical ripening was obtained with the transcervical catheter in 46 women (29.6%). One hundred six women (68.4%) had vaginal delivery. No correlation was found among maternal body mass index, maternal age, clinical cervical dilatation, sonographic posterior cervical angle, and any of the outcomes of interest. Multiple logistic regression showed that preripening sonographic cervical length was an independent predictor of successful ripening (odds ratio [OR] 10.2, 95% confidence interval [CI] 3.6 to 28.5), vaginal delivery (OR 2.6, 95% CI 1.2 to 5.5), vaginal delivery achieved with only Foley (OR 17.2, 95% CI 3.9 to 76.2), and vaginal delivery within 24 hours (OR 3.3, 95% CI 1.5 to 7.3). In the subgroup of women who did not enter labor with the transcervical Foley, at the time of catheter removal, a significant change was found in sonographic cervical length (33.1 mm [12.2 to 54.1] vs 24.0 mm [7.6 to 42], P < .0001] and sonographic posterior cervical angle (110 degrees C [70-160] vs 137 degrees C [88-170], P < .0001), compared with preripening findings. Transvaginal ultrasound cervical length was the only postripening characteristic that independently predicted vaginal delivery (OR 3.5, 95% CI 1.3 to 9.1).

CONCLUSION

Transvaginal sonography seems a useful diagnostic tool to assess objectively the efficacy of the Foley catheter as ripening method and helps predict the likelihood of a successful induction of labor in individual women who require preinduction cervical ripening.

Mechanical Methods of Cervical Ripening and Labor Induction

This article reviews the safety and efficacy of mechanical agents for cervical ripening. Hygroscopic dilators, balloon catheters, and devices designed for cervical ripening have all been shown to be safe and effective for cervical ripening. Mechanical agents are as efficacious as other agents for cervical ripening. However, there is no method that has been conclusively shown to improve mode of delivery or perinatal outcome. The advantages of preinduction cervical ripening with mechanical devices include low cost, low incidence of systemic side effects, and low risk of uterine hyperstimulation.

Fetal Fibronectin as a Predictor of Vaginal Birth in Nulliparas Undergoing Preinduction Cervical Ripening

OBJECTIVE

We sought to evaluate whether the presence of a positive fetal fibronectin (> or = 50 ng/mL) in nulliparous women undergoing preinduction cervical ripening with the intracervical Foley catheter predicted vaginal birth.

METHODS

This was a prospective blinded observational trial of nulliparous women undergoing preinduction cervical ripening. We excluded women who had a contraindication to vaginal birth. Cervical and vaginal fetal fibronectin specimens were obtained before preinduction cervical ripening with an intracervical Foley catheter. The managing obstetrician was blinded to these results.

RESULTS

A total of 241 women met the inclusion criteria, of which 54.4% delivered vaginally. There was no difference in the rate of vaginal delivery among women with either a positive cervical fetal fibronectin (positive fetal fibronectin 55.8% compared with negative fetal fibronectin 53.3%, P = .70) or positive vaginal fetal fibronectin (positive fetal fibronectin 57.6% compared with negative fetal fibronectin 53.3%, P = .56). Women with a positive cervical fetal fibronectin did have a shorter duration of cervical ripening (fetal fibronectin-positive 229 +/- 220 minutes compared with fetal fibronectin-negative 379 +/- 193 minutes, P < .05), duration of oxytocin (fetal fibronectin-positive 655 +/- 555 minutes compared with fetal fibronectin-negative 731.5 +/- 342 minutes, P < .025) and required lower maximal doses of oxytocin (fetal fibronectin-positive 18.4 mIU/min compared with fetal fibronectin-negative 21.8 mIU/min, P = .005). Women with a positive vaginal fetal fibronectin demonstrated only a shorter duration of cervical ripening compared with their fetal fibronectin negative counterparts (fetal fibronectin-positive 300 +/- 216 minutes compared with fetal fibronectin-negative 345 +/- 201 minutes, P < .05).

CONCLUSION

Fetal fibronectin does not predict vaginal delivery in nulliparous women requiring preinduction cervical ripening.

LEVEL OF EVIDENCE

II-2.

Intravaginal misoprostol versus Foley catheter for cervical ripening and induction of labor

OBJECTIVE

To compare the efficacy and safety of 100 microg of intravaginal misoprostol with intracervical Foley catheter for cervical ripening and induction of labor.

METHOD

One hundred women being induced in the Lagos University Teaching Hospital, Nigeria, were randomized to receive a single 100 microg dose of misoprostol intravaginally or intracervical insertion of Foley catheter. Data analyses were by the Student's t-test and chi-square test.

RESULT

Misoprostol was more effective in terms of induction to delivery interval (11.84+/-5.43 versus 20.03+/-4.68 h, P<0.05), change in Bishop score, and number delivered within 24 h, in patients with a one-time successful induction. Uterine hyperactivity and rupture were more frequent in the misoprostol group.

CONCLUSION

A single 100 microg dose of intravaginal misoprostol is more efficacious than intracervical insertion of Foley catheter for cervical ripening and induction of labor. Further studies using lower doses are needed to determine the safest dose.

Hyaluronidase versus Foley catheter for cervical ripening in high-risk term and post term pregnancies

OBJECTIVE

To evaluate the effectiveness and safety of Foley catheter and hyaluronidase for cervical ripening.

METHOD

Randomized controlled trial where 140 pregnant women, with gestational age > or = 37 weeks, indication for labor induction and an unripe cervix, were enrolled, allocated in two groups according to the method of cervical ripening before labor induction. Statistical analysis used Student's t-test, Mann-Whitney, Chi-square test, survival analysis, risk ratios and number needed to treat.

RESULTS

Time of induction, dose of oxytocin and mode of delivery had better results in the Foley catheter group. Comfort with the method was higher in the hyaluronidase group.

CONCLUSIONS

Both methods were effective and safe for cervical ripening. The Foley catheter group experienced a shorter period of induction, required a lower dose of oxytocin and had higher vaginal delivery rates, while the women who used hyaluronidase declared greater comfort with the method.

Preinduction cervical ripening with the Foley catheter and the risk of subsequent preterm birth

OBJECTIVE

The Foley catheter is a safe and effective form of preinduction cervical ripening and is quickly growing in popularity. Its major effect appears to be through mechanical dilation, which has raised the concern that the use of the Foley catheter for cervical ripening may damage the cervix and result in a higher rate of subsequent preterm birth.

STUDY DESIGN

We conducted a review of all induction of labor at our institution from July 1998 to July 2001 that required preinduction cervical ripening and had a subsequent birth. The primary outcome variable was preterm birth at <35 weeks of gestation. Demographic and potential confounding variables were analyzed. A probability value of <.05 was considered significant.

RESULTS

The cases of 126 women (63 women in the Foley group and 63 women in the prostaglandin group) were studied. Women in the prostaglandin group had a prostaglandin agent used. There was no difference in maternal age, gravidity, parity, Bishop score, total time of induction, gestational age, oxytocin use, maximum oxytocin level, tobacco or drug use, or type of delivery in the index pregnancy between the groups. In the subsequent pregnancies, there were no differences in maternal age, gravidity, parity, spontaneous abortions, terminations, cone or Loop Electrosurgical Excision Procedure (LEEP) procedures, history of cervical manipulation, tobacco or drug use, stillbirth, need for induction, mode of delivery, episiotomy, gestational age at delivery, Apgar scores, labor duration, use of oxytocin, or birth weight. There were no differences in preterm birth at 37, 35, or 32 weeks of gestation between the groups.

CONCLUSION

The use of the Foley catheter for preinduction cervical ripening does not appear to increase the risk of preterm birth in a subsequent pregnancy.

Cervical Ripening With Transcervical Foley Catheter and the Risk of Uterine Rupture

OBJECTIVE

To estimate whether the rate of uterine rupture in patients with a previous cesarean delivery is related to labor induction and/or cervical ripening using transcervical Foley catheter.

METHODS

Charts of all patients who had a trial of labor after a previous cesarean delivery in our institution between 1988 and 2002 were reviewed. The rates of successful vaginal birth after cesarean delivery and uterine rupture in patients with spontaneous labor (control group) were compared with those of patients who underwent a labor induction by means of amniotomy with or without oxytocin and patients who underwent a labor induction/cervical ripening using a transcervical Foley catheter. Logistic regression analysis was performed to adjust for confounding variables.

RESULTS

Of 2479 patients, 1807 had a spontaneous labor, 417 had labor induced by amniotomy with or without oxytocin, and 255 had labor induced by using transcervical Foley catheter. The rate of successful vaginal birth after cesarean delivery was significantly different among the groups (78.0% versus 77.9% versus 55.7%, P <.001), but not the rate of uterine rupture (1.1% versus 1.2% versus 1.6%, P =.81). After adjusting for confounding variables, the odds ratio (OR) for successful vaginal birth after cesarean delivery was 0.68 (95% confidence interval [CI] 0.41, 1.15), and the OR for uterine rupture was 0.47 (95% CI 0.06, 3.59) in patients who underwent an induction of labor using a transcervical Foley catheter when compared with patients with spontaneous labor.

CONCLUSION

Labor induction using a transcervical Foley catheter was not associated with an increased risk of uterine rupture.

Intracervical Foley catheter balloon vs. prostaglandin in preinduction cervical ripening

OBJECTIVES

The aim of this study is to compare the effectiveness of the intracervical Foley balloon catheter and 3 mg prostaglandin E(2) tablet(s) in preinduction cervical ripening.

METHODS

Ninety women referred to the maternity clinic for induction of labor with a Bishop score of less than or equal to 5 were randomized to receive an intracervical Foley catheter or prostaglandin E(2) tablets. The primary measured outcome was ripening of the cervix as measured with the Bishop score.

RESULTS

There were no differences in mean Bishop scores between the prostaglandin and the Foley catheter groups. Bishop scores (mean+/-S.D.) after ripening were 6.6+/-0.80 and 6.7+/-0.86 for the Foley catheter and prostaglandin groups, respectively (P=0.54). The Foley catheter group showed a statistically shorter time to ripening compared with the prostaglandin group (3.4+/-2.1 and 6.5+/-3.2 h, respectively (P=0.001). There was no statistically significant difference in induction time (4.8+/-1.8 h and 5.3+/-2.4 h, respectively (P=0.36).

CONCLUSIONS

There are no differences in preinduction cervical ripening efficacy between prostaglandin E(2) and the Foley catheter, but the Foley catheter has the advantage of ripening an unfavorable cervix in a shorter time.

A comparison of vaginally administered misoprostol with extra-amniotic saline solution infusion for cervical ripening and labor induction

OBJECTIVE

The purpose of this study was to compare intravaginal misoprostol with extra-amniotic saline solution infusion with concomitant oxytocin for cervical ripening and labor induction in viable pregnancies.

STUDY DESIGN

Two hundred women with indications for labor induction and unfavorable cervices were assigned randomly to vaginal misoprostol or extra-amniotic saline solution infusion. Twenty-five micrograms of misoprostol was administered every 4 hours up to six doses, followed by intravenous oxytocin administration. Patients who had received extra-amniotic saline solution infusion also received intravenous oxytocin along with a maximum 12-hour saline solution infusion through Foley catheters that were placed above the internal cervical os.

RESULTS

One hundred women were randomly assigned to misoprostol, and 100 women were assigned randomly to extra-amniotic saline solution infusion. The average interval from start of induction to vaginal delivery was longer in the misoprostol group (1323.3 +/- 700.3 minutes) than in the extra-amniotic saline solution infusion group (970.4 +/- 502.7 minutes; P =.006, log transformed data). Abnormal fetal heart rate tracings were found in 30% of the patients who received misoprostol and in 19% of the patients who received extra-amniotic saline solution infusion (relative risk, 1.6; 95% CI, 1.0-2.4; P =.05). There was more tachysystole in the misoprostol group (8%) than in the extra-amniotic saline solution infusion group (1%; P =.02). There were no differences in the routes of deliveries or neonatal outcomes between groups.

CONCLUSION

Extra-amniotic saline solution infusion with oxytocin administration appears more effective and is associated with fewer maternal complications than misoprostol for cervical ripening and labor induction.

Ripening of the uterine cervix in a post-cesarean parturient: prostaglandin E2 versus Foley catheter

OBJECTIVE

To compare the success and complication rates of prostaglandin E2 tablets (PGE2) and a Foley catheter for the ripening of the uterine cervix in post-Cesarean section parturients.

STUDY DESIGN

The study population in this retrospective cohort study consisted of parturients in their second pregnancy who had undergone Cesarean section in their previous delivery and who underwent ripening of the uterine cervix by using PGE2 (n = 55) or Foley catheter (n = 161) in the current pregnancy. The control group consisted of 1432 post-Cesarean section parturients without induction of labor. We compared the rates of placental abruption, non-reassuring fetal heart rate patterns, intrapartum fetal deaths (IPFD), uterine rupture, Apgar scores, labor dystocia, severe birth canal lacerations, vacuum deliveries and repeated Cesarean section rates in the three groups by using ANOVA, chi2 analysis and Fisher's exact test when appropriate.

RESULTS

A significant increase in the rates of labor dystocia during the first stage (30.4% vs. 11.6%, p < 0.01) and repeated Cesarean deliveries (49.1% vs. 35.2%, p < 0.01) were observed in women in whom the Foley catheter was used as compared to controls, respectively. No such changes were demonstrated in the PGE2 group as compared to the controls. No significant differences were found between the PGE2 group and Foley catheter group as compared to the controls in rates of placental abruption, IPFD, uterine rupture, fetal distress, birth canal lacerations, vacuum deliveries and Apgar scores.

CONCLUSIONS

PGE2 was found to be superior to the Foley catheter for ripening of the uterine cervix in a post-Cesarean parturient, as demonstrated by a lower repeated Cesarean delivery rate.

A randomised comparison of early versus late amniotomy following cervical ripening with a Foley catheter

OBJECTIVES

Ripening of the cervix with a Foley catheter commonly results in cervical dilatation without contractions. We examined the outcome of labour in women who underwent induction of labour using a Foley catheter, followed by either 1. early amniotomy, or 2. augmentation of labour by oxytocin and late amniotomy.

DESIGN

Prospective randomised clinical trial.

SETTING

Labour and delivery ward of a university teaching hospital.

PARTICIPANTS

Pregnant women > or =38 weeks of a singleton gestation, who had had no prior caesarean section.

METHODS

All women underwent cervical ripening using a Foley catheter. Following removal of the catheter, women were randomly assigned to either early (n = 80) or late amniotomy (n = 88).

MAIN OUTCOME MEASURES

Comparison of mode of delivery and duration of labour between the two groups.

RESULTS

The rate of caesarean section was significantly higher in the early amniotomy group compared with the late amniotomy group (25% vs 7.9%; relative risk 1.74; 95% CI 1.3 - 2.34). The increase in caesarean section rate was due primarily to dystocia (15% vs 3.3%; relative risk 1.8; 95% CI 1.32 - 2.45). When excluding caesarean deliveries, no significant difference was found in duration of labour between the groups (8.3 hours (3.8) vs 7.7 hours (2.9)).

CONCLUSIONS

In women who undergo cervical ripening with a Foley catheter, augmentation of labour by oxytocin followed by amniotomy during active labour results in a lower rate of caesarean delivery for dystocia.

Randomized trial of concurrent oxytocin with a sustained-release dinoprostone vaginal insert for labor induction at term

OBJECTIVE

The purpose of this study was to determine whether the concurrent administration of oxytocin with sustained-release dinoprostone results in shorter induction times when compared with oxytocin after the removal of the dinoprostone insert.

STUDY DESIGN

Women with singleton pregnancies at > or = 36 weeks, vertex presentations, reactive nonstress tests, no prior uterine scar, intact membranes, and Bishop scores of < or = 6 were randomly assigned to receive oxytocin either immediately after placement of a sustained-release dinoprostone insert (immediate) or 30 minutes after its removal (delayed). The primary outcome was the time interval from induction to delivery.

RESULTS

Seventy-one patients were enrolled (immediate, 34 patients; delayed, 37 patients). There were no differences between treatment groups in non-reassuring fetal heart tracings, excess uterine activity, and epidural use. The mean time from dinoprostone placement until delivery was 544 minutes, shorter in the immediate group (972 vs 1516 minutes; P =.001). The proportion of deliveries within 24 hours was higher (90% vs 53%; P =.002) in the immediate group. Cesarean delivery rates were similar between the immediate and delayed groups (16% vs 13%; P =.73). No adverse maternal or neonatal outcomes were observed with concurrent therapy.

CONCLUSION

Oxytocin that is administered concurrently with sustained-release dinoprostone significantly shortens induction-to-delivery times and results in a higher proportion of vaginal deliveries of < or = 24 hours with no apparent adverse effects.