Misoprostol versus Foley catheter insertion for induction of labor in pregnancies affected by fetal growth restriction

Association of Prostaglandin Use for Cervical Ripening with Mode of Delivery in Small for Gestational Age versus Non-Small for Gestational Age Neonates

OBJECTIVE

Prostaglandins (PGs) use for cervical ripening with small for gestational age (SGA) fetuses is controversial since it remains uncertain if use increases the chance of cesarean delivery (CD). We aimed to assess the association between PG use for cervical ripening and mode of delivery between SGA and appropriate for gestational age (AGA) neonates.

STUDY DESIGN

Secondary analysis of the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nuMoM2b), a prospective observational cohort study of 10,038 nulliparas. We included women undergoing induction with nonanomalous fetuses in the cephalic presentation. Women with >2 cm cervical dilation or prior uterine scar were excluded. We assessed the association of PG use with CD among women with SGA and AGA neonates. SGA was defined as birth weight <10th percentile for gestational age and sex. Multivariable logistic regression was used to adjust for potential confounders and test for interaction. Secondary outcomes included adverse neonatal outcomes, indication for CD, maternal hemorrhage, and chorioamnionitis.

RESULTS

Among 2,353 women eligible, PGs were used in 54.8%, SGA occurred in 15.1%, and 35.0% had CD. The association between PG use and CD differed significantly (interaction p = 0.018) for SGA versus AGA neonates; CD occurred more often in SGA neonates exposed to PGs than not (35 vs. 22%, p = 0.009). PG use was not associated with CD among AGA neonates (36 vs. 36%, p = 0.8). This effect remained significant when adjusting for body mass index, race/ethnicity, and cervical dilation. Among SGA neonates, CD for "nonreassuring fetal status" was similar between PG groups. Among SGA neonates, PG use was not associated with adverse neonatal outcomes or postpartum hemorrhage but had a higher rate of chorioamnionitis (7.0 vs. 2.1%, p = 0.048).

CONCLUSION

PG use was associated with a higher rate of CD in SGA but not AGA neonates; however, further studies are needed before PG use is discouraged with SGA neonates.

KEY POINTS

· PGs are commonly used for cervical ripening.. · PG use was associated with increased risk of cesarean delivery in SGA neonates.. · PG use was not associated with adverse neonatal outcomes..

[Chances of vaginal delivery with induction in severe preterm SGA fetus: An observational study]

OBJECTIVE

If a small for gestational age (SGA) foetus needs to be delivered because of severity (<3rd centile) attempting induction of labor theoretically increases the risk of caesarean section and neonatal acidosis, but these risks are poorly understood. This article aims to assess the risk of caesarean section and neonatal acidosis in attempted vaginal birth of a moderately preterm foetus in the setting of severe SGA.

METHOD

A single-centre hospital-based observational study conducted over a period of 17 consecutive years in mothers with a single foetus in cephalic presentation with severe SGA (<3rd centile) needing foetal extraction. Neonatal acidosis was considered moderate if pH<7.10 and severe if pH<7.0. The degree of severity of SGA was estimated according to the birth weight ratio.

RESULTS

Four hundred and thirty-four foetuses with severe SGA were included during the period, 140 of whom were born after induction (32.3%). In this group, 66.4% of women achieved a vaginal birth (66.4%; 95% CI [58.0-74.2]) and the risk of moderate or severe acidosis was doubled compared with the group of foetuses who had undergone a planned caesarean section (7.9% vs. 3.1%, OR=2.7 [1.1-6.7]). Neither gestational age nor the degree of growth restriction was significantly related to the risk of caesarean section or to the risk of moderate or severe neonatal acidosis.

CONCLUSION

In cases of severe SGA before 37weeks' gestation, induction of labour allows vaginal delivery in two-thirds of cases. It is accompanied by a doubling of the risk of moderate or severe neonatal acidosis.

[Prostaglandins or cervical balloon for the induction of labor for cervical ripening: A literature review]

OBJECTIVE

Induction of labor in France concerns one birth out of four with 70% of induction starting by cervical ripening, either with a pharmacological (prostaglandins) or a mechanical (balloon) method. This review aims to compare these two methods within current knowledge, using the PRISMA methodology.

METHODS

Trials comparing these two methods, published or unpublished up to July 2023, in French or English were searched for in the PubMed, Cochrane Library and ClinicalTrial.govs datasets. Fifty articles including 10,689 women were selected. The outcomes of interest were those from the Core Outcome Set for trails on Induction of Labour (COSIOL) list: mode of delivery, time from induction-to-birth, maternal and neonatal morbidity, and maternal satisfaction.

RESULT

No differences were observed between the two methods for the mode of delivery or neonatal and maternal morbidity. The time from induction-to-birth was longer for mechanical methods. Those were also associated with a greater need for oxytocin, less uterine hyperstimulation and less instrumental deliveries. Maternal satisfaction was assessed in only nine trials using various scales which made the interpretation of maternal satisfaction.

CONCLUSION

The efficacy of these two induction methods is similar for vaginal delivery, but it remains to be seen which one best meets women's satisfaction criteria.

Misoprostol with balloon vs oxytocin with balloon in high-risk pregnancy induction: a randomized controlled trial

BACKGROUND

Pregnancies at high risk for maternal, fetal, or placental complications often necessitate induction of labor in the late preterm or early term period for delivery. Limited data exist on the safest method of induction to use in this specific patient population.

OBJECTIVE

This study aimed to compare the combination of oxytocin plus a Cook balloon vs misoprostol plus a Cook balloon for induction of labor in high-risk pregnancies.

STUDY DESIGN

We conducted an open-label, randomized controlled trial at a single institution from July 2020 to May 2022. The study was approved by the institutional review board and registered with ClinicalTrials.gov (NCT04492072). Individuals with a high-risk pregnancy, at least ≥22 weeks' gestation, with a singleton in cephalic presentation, Bishop score ≤6, and intact membranes were offered enrollment. A high-risk pregnancy was defined as a pregnancy with any of the following complications: hypertensive disease of pregnancy, fetal growth restriction, oligohydramnios, suspected placental abruption requiring delivery, uncontrolled pregestational diabetes, or abnormal biophysical profile or nonstress test requiring delivery. The primary outcome was the rate of cesarean delivery. Secondary maternal outcomes included induction to delivery interval, number of vaginal deliveries within 24 hours, rates of uterine tachysystole, intraamniotic infection, operative vaginal delivery, and postpartum hemorrhage. Secondary fetal outcomes included fetal heart rate abnormalities, stillbirth, Apgar scores <7 at 5 minutes, admission to the neonatal intensive care unit, arterial umbilical blood pH <7.1, sepsis, and neonatal death. A subgroup analysis was planned for the primary outcome to assess the different indications for cesarean delivery. An intent-to-treat analysis was performed.

RESULTS

During the 22 months of the trial, a total of 150 patients were randomized, and 73 (49%) of those were induced with oxytocin and a Cook balloon and 77 (51%) were induced with misoprostol and a Cook balloon. There was no significant difference in the overall rate of cesarean delivery between the study groups, (21.9% vs 31.1%; relative risk, 0.70; 95% confidence interval, 0.41-1.21), nor among those for which the cesarean delivery was performed for a specific indication. There were no differences in the secondary maternal and fetal or neonatal adverse outcomes.

CONCLUSION

In high-risk pregnancies, the rate of cesarean delivery and adverse maternal and fetal outcomes were similar for induction of labor with oxytocin and a Cook balloon and for induction with misoprostol and a Cook balloon.

Is there a difference in labor patterns after induction with prostaglandins and double-balloon catheters?

BACKGROUND

Labor progression curves are believed to differ between spontaneous and induced labors. However, data describing labor progression patterns with different modes of induction are insufficient.

OBJECTIVE

This study aimed to compare the progress patterns between labors induced with slow-release prostaglandin E2 vaginal analogue and those induced with a double-balloon catheter.

STUDY DESIGN

This retrospective cohort study included all nulliparous women who delivered at term and who underwent cervical ripening with prostaglandin E2 vaginal analogue or a double-balloon catheter from 2013 to 2021 in a tertiary hospital in Israel. Included in the analysis were women who achieved 10 cm cervical dilatation. The time intervals between centimeter-to-centimeter changes were evaluated.

RESULTS

A total of 1087 women were included of whom 786 (72.3%) were induced using prostaglandin E2 vaginal analogue and 301 (27.7%) were induced using a double-balloon catheter. The time from induction to birth was similar between the groups (32.5 hours for the prostaglandin E2 vaginal analogue group [5th-95th percentiles, 6.5-153.8] vs 29.2 hours for the double-balloon group [5th-95th percentiles, 9.1-157.1]; P=.100). The median time of the latent phase (2-6 cm dilation) was longer for the double-balloon catheter group than for the prostaglandin E2 vaginal analogue group (7.3 hours [5th-95th percentiles, 5.6-14.5] vs 6.0 hours [5th-95th percentiles, 2.4-18.8]; P=.042). The median time of active labor (6-10 cm dilatation) was similar between groups (1.9 hours [5th-95th percentiles, 0.3-7.4] for the prostaglandin E2 vaginal analogue group vs 2.3 hours [5th-95th percentiles, 0.3-6.5] for the double-balloon catheter group; P=.307).

CONCLUSION

Deliveries subjected to cervical ripening with a double-balloon catheter were characterized by a slightly longer latent phase than deliveries induced by prostaglandin E2 vaginal analogue. After reaching the active phase of labor, the mode of cervical ripening did not influence the labor progress pattern.

Delivery Mode among Patients with Oligohydramnios with or without Fetal Growth Restriction by Induction Method

OBJECTIVE

This study aimed to evaluate the association of induction method on delivery mode in pregnancies complicated by oligohydramnios with and without fetal growth restriction (FGR).

STUDY DESIGN

This was a secondary analysis of a National Institutes of Health funded retrospective cohort study of singleton deliveries at a tertiary-care hospital between 2002 and 2013 with diabetes, mild hypertension, and/or FGR. Chart abstraction was performed by trained research nurses. Patients with a diagnosis of fetal oligohydramnios with and without FGR were identified. Our analytic cohort was further stratified into three groups per initial induction agent: prostaglandins (PGEs) alone, PGE plus mechanical ripening, or oxytocin only. Primary outcome was mode of delivery. Secondary outcomes included indications for cesarean delivery and neonatal morbidity.

RESULTS

Out of 4,929 patients in the original database, 546 subjects with fetal oligohydramnios were identified; of these, 270 were induced and included for analysis. Outcomes were compared between 171 patients who had fetuses with isolated oligohydramnios and 99 patients who had fetuses with oligohydramnios and FGR. There were no significant differences in demographic characteristics between the groups. Patients with fetuses with isolated oligohydramnios had similar rates of spontaneous vaginal delivery (SVD) when PGEs were used (n = 44/79, 55.7% PGE alone, n = 44/76, 57.9% PGE with mechanical ripening) and when they were not used (n = 5/13, 38.5% oxytocin alone; p = 0.43). Similarly, the majority of patients in both cohorts underwent SVD regardless of induction method (n = 30/44, 68.2% PGE alone, n = 30/44, 68.2% PGE with mechanical ripening, and n = 6/10, 60% oxytocin alone; p = 0.90). There was no significant difference in composite neonatal morbidity.

CONCLUSION

In patients with fetuses with oligohydramnios with and without FGR, most patients delivered by SVD regardless of induction method. In this population, PGE use was associated with a high chance of SVD in patients with fetuses with suspected placental insufficiency regardless of the presence of absence of FGR.

KEY POINTS

· The majority of fetuses with oligohydramnios with or without FGR deliver vaginally.. · The use of prostaglandins did not increase rates of cesarean for fetal distress in oligohydramnios.. · Prostaglandin use did not increase rate of neonatal intensive care unit admission among pregnancies with oligohydramnios..

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.

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

OBJECTIVE

To evaluate the safety aspects of different induction methods in pregnancies with small-for-gestational-age neonates.

STUDY DESIGN

This was a secondary analysis of two previously reported multicenter, randomized controlled trials conducted in the Netherlands. In the original trials, women were randomized to either a 30 cc Foley catheter, vaginal prostaglandin E2 (PROBAAT-1) or oral misoprostol (PROBAAT-2). A total of 425 patients with a term, singleton pregnancy in cephalic presentation with an indication for labor induction and a small-for-gestational-age neonate were included in this secondary analysis. Our primary outcome was a composed adverse neonatal outcome of Apgar score < 7 after 5 min and/or a pH in the umbilical artery < 7.05 and/or NICU admission. Secondary outcomes were mode of birth, operative birth for fetal distress and pH < 7.10 in the umbilical artery. For these outcome measures, multivariate as well as bivariate analyses were performed.

RESULTS

An adverse neonatal outcome occurred in 4.7 % (10/214) induction with a Foley catheter, versus 12.8 % (19/149) after misoprostol (RR 0.36; 95 % CI 0.17-0.76) and 4.7 % (3/64) after Prostaglandin E2 (RR 0.98; 95 %CI 0.28-3.51). For individual components of the composed outcome of adverse events, a difference was found between a Foley catheter and misoprostol for Apgar score < 7 at 5 min (0.5 % versus 3.4; RR 0.14; 95 %CI 0.02-1.16) and NICU admission (1.9 % versus 6.1 %; RR 0.31; 0.10-0.97). No differences were found for mode of birth.

CONCLUSIONS

For women who gave birth to a small-for-gestational-age neonate, a Foley catheter is probably a safer induction method compared to oral misoprostol.

Maternal and neonatal outcomes following induction of labor for fetal growth restriction: Extra-amniotic balloon versus prostaglandins

OBJECTIVE

To compare perinatal outcomes in pregnancies with fetal growth restriction (FGR) undergoing induction of labor by extra-amniotic balloon (EAB) versus prostaglandin E₂ (PGE₂ ).

METHODS

A retrospective cohort study of women with singleton pregnancies and FGR, undergoing induction at term via EAB, PGE₂ , or both, at a single medical center (2014-2017). Primary outcome was rate of cesarean deliveries (CDs). Secondary outcomes included composite maternal and neonatal outcomes.

RESULTS

Overall, 266 women met the inclusion criteria. Among them, 131 (49.2%) underwent induction by PGE₂ , 116 (43.6%) by EAB, and 19 (7.14%) by both methods. No differences were noted in baseline characteristics. Rate of CD (17.24% vs. 6.11% vs. 10.53%, P = 0.022) and maternal composite outcome (18.97% vs. 6.11% vs. 10.53%, P < 0.01) were higher among women who underwent induction by EAB compared with PGE₂ or both. No difference was noted between groups in neonatal outcomes. In a multivariable logistic regression, rates of cesarean delivery and composite maternal outcome were no longer higher in the EAB group (adjusted odds ratio [aOR] 1.68, 95% confidence interval [CI] 0.68-4.16, P = 0.260; and aOR 1.94, 95% CI 0.84-4.45, P = 0.120, respectively).

CONCLUSION

EAB and PGE₂ have comparable maternal and neonatal outcomes when used for induction of labor due to FGR.

Balloon catheters versus vaginal prostaglandins for labour induction (CPI Collaborative): an individual participant data meta-analysis of randomised controlled trials

BACKGROUND

Induction of labour is one of the most common obstetric interventions globally. Balloon catheters and vaginal prostaglandins are widely used to ripen the cervix in labour induction. We aimed to compare the effectiveness and safety profiles of these two induction methods.

METHODS

We did an individual participant data meta-analysis comparing balloon catheters and vaginal prostaglandins for cervical ripening before labour induction. We systematically identified published and unpublished randomised controlled trials that completed data collection between March 19, 2019, and May 1, 2021, by searching the Cochrane Library, ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, and PubMed. Further trials done before March 19, 2019, were identified through a recent Cochrane review. Data relating to the combined use of the two methods were not included, only data from women with a viable, singleton pregnancy were analysed, and no exclusion was made based on parity or membrane status. We contacted authors of individuals trials and participant-level data were harmonised and recoded according to predefined definitions of variables. Risk of bias was assessed with the ROB2 tool. The primary outcomes were caesarean delivery, indication for caesarean delivery, a composite adverse perinatal outcome, and a composite adverse maternal outcome. We followed the intention-to-treat principle for the main analysis. The primary meta-analysis used two-stage random-effects models and the sensitivity analysis used one-stage mixed models. All models were adjusted for maternal age and parity. This meta-analysis is registered with PROSPERO (CRD42020179924).

FINDINGS

Individual participant data were available from 12 studies with a total of 5460 participants. Balloon catheters, compared with vaginal prostaglandins, did not lead to a significantly different rate of caesarean delivery (12 trials, 5414 women; crude incidence 27·0%; adjusted OR [aOR] 1·09, 95% CI 0·95-1·24; I²=0%), caesarean delivery for failure to progress (11 trials, 4601 women; aOR 1·20, 95% CI 0·91-1·58; I²=39%), or caesarean delivery for fetal distress (10 trials, 4441 women; aOR 0·86, 95% CI 0·71-1·04; I²=0%). The composite adverse perinatal outcome was lower in women who were allocated to balloon catheters than in those allocated to vaginal prostaglandins (ten trials, 4452 neonates, crude incidence 13·6%; aOR 0·80, 95% CI 0·70-0·92; I²=0%). There was no significant difference in the composite adverse maternal outcome (ten trials, 4326 women, crude incidence 22·7%; aOR 1·02, 95% CI 0·89-1·18; I²=0%).

INTERPRETATION

In induction of labour, balloon catheters and vaginal prostaglandins have comparable caesarean delivery rates and maternal safety profiles, but balloon catheters lead to fewer adverse perinatal events.

FUNDING

Australian National Health and Medical Research Council and Monash Health Emerging Researcher Fellowship.

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.

Prognostic factors for successful induction of labor in intrauterine growth restriction after 36 weeks of gestation

OBJECTIVE

In comparison to eutrophic fetuses, intra uterine growth restriction fetuses (IUGR) have a higher risk of perinatal morbi-mortality. There are no guidelines on the labor induction of labor (IOL) method to be performed in IUGR. The main objective was to determine fetal and maternal predictive factors of successful induction in IUGR fetuses from 36 weeks. Study design We conducted a retrospective cohort single-center study including 320 women with a cephalic fetal presentation. Labour was induced after 36 weeks for suspected IUGR between January 2013 and December 2019.

RESULTS

Among the 320 patients, 246 were delivered vaginally (76.9 %) and 74 had a cesarean (23.1 %). Prognostic factors for successful IUGR induction were nonscarring uterus (OR 8.41; 95 %CI [2.92-24.21]), absence of preeclampsia (OR 7.14; 95 %CI [2.42-21.03]), multiparity (OR 4.32; 95 %CI [1.83-10.18]), normal fetal heart rate before IOL (OR 2.99; 95 %CI [1.24-7.22]) and BMI < 30 (OR 3.54; 95 %CI [1.62-7.72]). Doppler abnormalities, method and number of line of IOL, cervical evaluation were not significant in our study.

CONCLUSION

The prognostic factors for successful IUGR induction are essentially maternal. Thus, a low BMI, multiparity, nonscarring uterus, absence of preeclampsia, and a normal FHR are good prognostic factors in IUGR induction.

Prostaglandins for induction in pregnancies with fetal growth restriction

BACKGROUND

The data on safety of prostaglandin agents for induction of pregnancies with fetal growth restriction is limited.

OBJECTIVE

To compare the rates of adverse outcomes among pregnancies with fetal growth restriction undergoing induction of labor with and without prostaglandins STUDY DESIGN: We performed a propensity-score-based secondary analysis of the Consortium on Safe Labor database. We included term, singleton, and nonanomalous pregnancies with fetal growth restriction (estimated fetal weight <10th percentile for gestational age). We excluded previous cesarean deliveries. The primary exposure was induction using prostaglandins (prostaglandin E₁ or prostaglandin E₂) compared with other methods. The primary outcome was a composite of adverse neonatal outcomes. The secondary outcomes included all cesarean deliveries and cesarean deliveries for nonreassuring fetal heart tracings. A subgroup analysis comparing the type of prostaglandin was planned a priori. The results are expressed as adjusted odds ratios with 95% confidence intervals.

RESULTS

Of 756 (0.3%) inductions, 212 (28%) used prostaglandins (108 prostaglandin E₁, 94 prostaglandin E₂), and 553 (72%) used nonprostaglandin methods, including oxytocin (348, 63%), amniotomy (211, 38%), and/or mechanical dilation (9, 1%). There were no differences in the composite of adverse neonatal outcomes between the prostaglandin (10.4%) and the nonprostaglandin group (6.7%), adjusted odds ratio, 1.39 (0.64-3.03). The rate of cesarean delivery was higher in the inductions that received prostaglandins than those that did not (25.5% vs 14.8%, adjusted odds ratio, 1.80; 1.07-3.02). The rate of cesarean delivery for nonreassuring fetal heart tracings was higher for those that received prostaglandins than those that did not (16.0% vs 8.7%, adjusted odds ratio, 2.37; 1.28-4.41). When prostaglandin E₁ and prostaglandin E₂ were examined independently, there were similar increases in the composite of adverse neonatal outcomes and cesarean delivery rates for both prostaglandin E₁ and prostaglandin E₂ compared with nonprostaglandin controls.

CONCLUSION

There were no differences in the composite of adverse neonatal outcomes when prostaglandins were used for induction in pregnancies with fetal growth restriction compared with other methods. However, there was a higher rate of cesarean delivery and cesarean delivery indicated for nonreassuring fetal heart tracings when prostaglandins (both prostaglandin E₁ and prostaglandin E₂) were used, compared with nonprostaglandin methods.

How and when to recommend delivery of a growth-restricted fetus: A review

Clinicians consider a range of variables when formulating decisions regarding the diagnosis, monitoring plan, and ultimately the decision to recommend the delivery of a growth-restricted fetus. The differential diagnosis of a pathological fetal growth pattern is initially considered via the history, a physical and laboratory examination of the pregnant person, as well as a comprehensive fetal ultrasound examination. These factors allow a broad distinction between pre-existing disease in the pregnant person, constitutionally small normal growth, placenta-mediated Fetal Growth Restriction (FGR), and intrinsic fetal disease. Most commonly, pathological growth restriction is mediated by underlying placental diseases, of which maternal vascular malperfusion is the most common, and often results in co-existent hypertension. A program of combined monitoring of the pregnant person and fetus, comprising hypertension assessment, and serial fetal ultrasound, including Doppler studies is then instituted, and may be combined with biochemical markers, such as Placental Growth Factor, for greater clinical precision. Recommendations on timing to deliver the growth-restricted fetus worldwide are converging, with similar guidance from clinical practice guidelines informed by high-quality Randomized Controlled Trials (RCTs) and large cohort studies. In most instances, it is reasonable to recommend delivery of all growth-restricted fetuses by approximately 38 weeks. Timing of delivery should take into consideration both short-term neonatal outcomes and long-term outcomes at school age. Mode of delivery is based on many factors, and induction of labor is a safe approach, especially after 34 weeks. Mechanical methods of induction may be preferred to pharmacologic methods, although both have a role and the choice of method is based on individualized assessment. Elective Cesarean birth thereby bypassing fetal stress during labor, is recommended in preterm growth-restricted fetuses with signs of adaptive fetal compromise, especially when ductus venosus flow is abnormal, or a contraction stress test is positive.

Experiences of induction of labor with a catheter - A prospective randomized controlled trial comparing the outpatient and inpatient setting

INTRODUCTION

Approximately every fourth labor is induced. In Finland, when labor is induced, it is commonly carried out with a catheter in the inpatient (IP) setting. However, in uncomplicated, full-term pregnancies, induction of labor (IOL) in the outpatient (OP) setting is also possible. Nevertheless, there is only a limited amount of information about the experiences of IOL in OP setting. Our study compared the experiences of catheter IOL in OP and IP settings.

MATERIAL AND METHODS

We performed a prospective randomized study, including 113 women with uncomplicated full-term pregnancies with planned IOL. After catheter insertion, women were randomized into OP or IP settings: after dropouts, there were 53 women in the OP group and 54 in the IP. The experiences of IOL were evaluated with three sets of visual analog scale (VAS) questionnaires: the general experience questionnaire (eight questions), the concurrent induction experience questionnaire (1, 5, 9, 13 hours; nine questions) and the postpartum experience questionnaire (14 questions).

RESULTS

Both groups had low VAS scores, indicating good experiences of IOL. Women in the OP group were less satisfied (mean VAS difference Δ = 7.8, P = .015) and more anxious (Δ = 4.8, P = .008) than were women in the IP group. In the course of the IOL, all women became less satisfied (Δ = 8.4, P = .001), had more contraction pain (Δ = 8.9, P = .020) and had a higher frequency of contractions (Δ = 9.9, P = .004) but they were more relaxed and experienced less fear (Δ = 6.9, P = .036, Δ = 5.3, P = .001, respectively). There was no interaction between group and time. According to the postpartum experience questionnaire, both groups had a similar good general experience of IOL (P = .736) but the OP group had more fear (Δ = 9.5, P = .009) and was more anxious (Δ = 9.0, P = .007). Most of the women would choose catheter IOL in a subsequent pregnancy (OP 82.6%, IP 87.0%).

CONCLUSIONS

The women in the OP setting were less satisfied and more anxious than were the women in the IP setting. However, the differences were marginal and the general experience after IOL was good. IOL in an OP setting is thus a viable option in low-risk full-term pregnancies. Therefore, when using catheter IOL, both setting options should be available.

Induction of labour with unfavourable local conditions for suspected fetal growth restriction after 36 weeks of gestation: Factors associated with the risk of caesarean

INTRODUCTION

Induction of labour in women with an unfavourable cervix is associated with a risk of caesarean delivery. When a diagnosis of fetal growth restriction (FGR) is also involved, the risk of intrapartum fetal acidosis increases. The main objective was to identify prognostic factors for the risk of caesarean delivery after induction for suspected FGR after 36 weeks of gestation with an unripe cervix.

MATERIAL AND METHODS

This was a retrospective, single-centre (Port Royal, Paris, France) study of women with a singleton fetus in cephalic presentation, with labour induced at or after 36 weeks for suspected FGR diagnosed during second or third trimester of pregnancy with an unripe cervix (Bishop score under 6) who gave birth between 1 January 2015 and 31 December 2019. A multivariable analysis was performed to identify the factors related to an increased risk of caesarean section.

RESULTS

Of the 146 women included, 56 (38.4 %) had caesarean deliveries. After adjustment, the factors significantly associated with the risk of caesarean were maternal age greater than 39 years (ORa = 4.33 [1.22-17.2], reference: 25-39 years), nulliparity (ORa = 3.49 [1.25-11.2]), and an abnormal fetal umbilical artery Doppler velocimetry (ORa = 3.50 [1.47-8.70]). The risk of poor neonatal condition did not differ significantly between women with vaginal and caesarean deliveries (2.3 % vs 7.3 %, P = 0.21).

CONCLUSION

When FGR is suspected at 36 weeks of gestation and later, induction of labour is a reasonable option, even if the cervix is unripe, as the risk of caesarean delivery appears acceptable and neonatal status is good and similar with both modes of delivery.

Adverse intrapartum outcome in pregnancies complicated by small for gestational age and late fetal growth restriction undergoing induction of labor with Dinoprostone, Misoprostol or mechanical methods: A systematic review and meta-analysis

OBJECTIVE

To investigate the outcome of pregnancies with small baby, including both small for gestational age (SGA) and late fetal growth restriction (FGR) fetuses, undergoing induction of labor (IOL) with Dinoprostone, Misoprostol or mechanical methods.

STUDY DESIGN

Medline, Embase and Cochrane databases were searched. Inclusion criteria were non-anomalous singleton pregnancies complicated by the presence of a small fetus, defined as a fetus with estimated fetal weight (EFW) or abdominal circumference (AC) <10th centile undergoing IOL from 34 weeks of gestation with vaginal Dinoprostone, vaginal misoprostol, or mechanical methods (including either Foley or Cook balloon catheters). The primary outcome was a composite measure of adverse intrapartum outcome. Secondary outcomes were the individual components of the primary outcome, perinatal mortality and morbidity. All the explored outcomes were reported in three different sub-groups of pregnancies complicated by a small fetus including: all small fetuses (defined as those with an EFW and/or AC <10th centile irrespective of fetal Doppler status), late FGR fetuses (defined as those with EFW and/or AC <3rd centile or AC/EFW <10th centile associated with abnormal cerebroplacental Dopplers) and SGA fetuses (defined as those with EFW and/or AC <10th but >3rd centile with normal cerebroplacental Dopplers). Quality assessment of each included study was performed using the Risk of Bias in Non-randomized Studies-of Interventions tool (ROBINS-I), while the GRADE methodology was used to assess the quality of the body of retrieved evidence. Meta-analyses of proportions and individual data random-effect logistic regression were used to analyze the data.

RESULTS

12 studies (1711 pregnancies) were included. In the overall population of small fetuses, composite adverse intra-partum outcome occurred in 21.2 % (95 % CI 10.0-34.9) of pregnancies induced with Dinoprostone, 18.0 % (95 % CI 6.9-32.5) of those with Misoprostol and 11.6 % (95 % CI 5.5-19.3) of those undergoing IOL with mechanical methods. Cesarean section (CS) for non-reassuring fetal status (NRFS) was required in 18.1 % (95 % CI 9.9-28.3) of pregnancies induced with Dinoprostone, 9.4 % (95 % CI 1.4-22.0) of those with Misoprostol and 8.1 % (95 % CI 5.0-11.6) of those undergoing mechanical induction. Likewise, uterine tachysystole, was recorded on CTG in 13.8 % (95 % CI 6.9-22.3) of cases induced with Dinoprostone, 7.5 % (95 % CI 2.1-15.4) of those with Misoprostol and 3.8 % (95 % CI 0-4.4) of those induced with mechanical methods. Composite adverse perinatal outcome following delivery complicated 2.9 % (95 % CI 0.5-6.7) newborns after IOL with Dinoprostone, 0.6 % (95 % CI 0-2.5) with Misoprostol and 0.7 % (95 % CI 0-7.1) with mechanical methods. In pregnancies complicated by late FGR, adverse intrapartum outcome occurred in 25.3 % (95 % CI 18.8-32.5) of women undergoing IOL with Dinoprostone, compared to 7.4 % (95 % CI 3.9-11.7) of those with mechanical methods, while CS for NRFS was performed in 23.8 % (95 % CI 17.3-30.9) and 6.2 % (95 % CI 2.8-10.5) of the cases, respectively. Finally, in SGA fetuses, composite adverse intrapartum outcome complicated 8.4 % (95 % CI 4.6-13.0) of pregnancies induced with Dinoprostone, 18.6 % (95 % CI 13.1-25.2) of those with Misoprostol and 8.7 (95 % CI 2.5-17.5) of those undergoing mechanical IOL, while CS for NRF was performed in 8.4 % (95 % CI 4.6-13.0) of women induced with Dinoprostone, 18.6 % (95 % CI 13.1-25.2) of those with Misoprostol and 8.7 % (95 % CI 2.5-17.5) of those undergoing mechanical induction. Overall, the quality of the included studies was low and was downgraded due to considerable clinical and statistical heterogeneity.

CONCLUSIONS

There is limited evidence on the optimal type of IOL in pregnancies with small fetuses. Mechanical methods seem to be associated with a lower occurrence of adverse intrapartum outcomes, but a direct comparison between different techniques could not be performed.

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.

Sublingual Misoprostol versus Foley catheter for cervical ripening in women with preeclampsia or gestational hypertension: A randomized control trial

Background

Delivery is the only definite cure for hypertensive disorders. Therefore, cervical ripening and labor induction are important to achieve favorable outcomes.

Objective

This Randomized Control Trial (RCT) is aimed to compare the effects of sublingual misoprostol and Foley catheter in cervical ripening and labor induction among patients with preeclampsia or gestational hypertension.

Materials and Methods

A total number of 144 women with preeclampsia or gestational hypertention with indication of pregnancy termination, who were referred to academic hospitals of the University of Medical Sciences in Mashhad, Iran, between March 2015 and December 2016, were randomly divided into two groups. In group one (n = 72), 25 µg of misoprostol tablet was administrated sublingually every 4 hr up to six doses. In group two (n = 72), a 16F Foley catheter was placed through the internal cervical os, inflated with 60 cc of sterile saline.

Results

There were no significant differences between groups regarding the demographic characteristics, primary bishop score, and pregnancy termination indication. The cervical ripening time (primary outcome) (8.2 vs 14.2 hr, p < 0.00), induction to delivery interval (15.5 vs 19.9 hr, p < 0.00), and vaginal delivery before 24 hr (63.9% vs 40%, p = 0.03) were significantly different between the two groups. There was no significant difference between groups in view of oxytocin requirement (p = 0.12), neonatal Apgar score (p = 0.84), or neonatal intensive care unit admission (p = 78).

Conclusion

This trial showed that the application of sublingual misoprostol, compared to the Foley catheter, can reduce cervical ripening period and other parameters related to the duration of vaginal delivery. This misoprostol regimen showed inconsiderable maternal complications.

Prostaglandins and cesarean delivery for nonreassuring fetal status in patients delivering small-for-gestational age neonates at term

Objective: Growth-restricted fetuses have been excluded from many randomized trials of prostaglandins for labor induction. As prostaglandins, particularly misoprostol, are associated with increased rates of cesarean delivery for nonreassuring fetal heart tracing, it is important to assess their safety in pregnancies at higher risk of this complication. The objective of this study was to estimate the association between use of prostaglandins for labor induction in term singleton pregnancies complicated by delivery of small-for-gestational age (SGA) neonates and the risk of cesarean delivery for nonreassuring fetal status (NRFS).Materials and methods: Retrospective cohort study of singleton deliveries ≥37 weeks following induction of labor in patients with SGA (birthweight <10% percentile for gestational age). Patients with prior cesarean delivery or neonates with major congenital anomalies were excluded. Patients were categorized by exposure to prostaglandins. The primary outcome was cesarean delivery for NRFS. Secondary outcomes were any cesarean delivery, a composite of a 5-min Apgar score <7, admission to the neonatal intensive care unit, or neonatal death, and a composite of maternal morbidity (transfusion, postpartum hemorrhage, wound infection, endometritis, fever). Propensity scores for exposure were estimated using a logistic regression model, including parity, comorbidities, and Bishop score. Stabilized weights from inverse probability of treatment weighting were used. Outcomes were compared with relative risks (RRs) and 95% confidence intervals (CIs).Results: There were 1097 patients: 587 (53.5%) exposed to prostaglandins and 510 (46.5%) unexposed. Covariates were balanced in the stabilized sample. Overall, 166 (15.1%) patients had cesarean deliveries for NRFS. In unadjusted analysis, prostaglandin use was associated with an increased RR of cesarean for NRFS (18.3 versus 11.0%, RR: 1.71, 95% CI: 1.27-2.30). In propensity-score-weighted analysis, the RR for cesarean for NRFS was 1.22 (95% CI: 0.93-1.59). There was no significant association between prostaglandin exposure and all-cause cesarean delivery, maternal morbidity, or neonatal morbidity.Conclusion: In propensity score analysis, there was no association between the use of prostaglandins for labor induction at term and cesarean for NRFS in pregnancies complicated by SGA. However, given the retrospective nature of the study, these results should be interpreted with caution.

Challenges and Limitations of Clinical Trials on Labor Induction: A Review of the Literature

Induction of labor is a common obstetric procedure performed in nearly a quarter of all deliveries in the United States. Pharmacological (prostaglandins, oxytocin) and/or mechanical methods (balloon catheters) are commonly used for labor induction; however, there is ongoing debate as to which method is the safest and most effective. This narrative review discusses key limitations of published trials on labor induction, including the lack of well-designed randomized controlled trials directly comparing specific methods of induction, heterogeneous trial populations, and wide variation in the protocols used and outcomes reported. Furthermore, the majority of published trials were underpowered to detect significant differences in the most clinically relevant efficacy and safety outcomes (e.g., cesarean delivery, neonatal mortality). By identifying the limitations of labor induction trials, we hope to highlight the importance of quality published data to better inform guidelines and drive evidence-based treatment decisions.

Comparison of prostaglandin and mechanical cervical ripening in the setting of small for gestational age neonates

Objective: The objective of this study is to determine whether cervical ripening with misoprostol (MP) is associated with higher rates of cesarean delivery (CD) compared with dinoprostone (DP) or Pitocin/Foley balloon (PFB) in infants found to be small for gestational age (SGA). Study design: Single center institution based cohort study of all inductions between 2008 and 2012 where birth weight was found to be as SGA (< 10th percentile). Maternal demographic, obstetric, and labor characteristics were compared between SGA births where cervical ripening with MP, DP, or PFB was used as the primary agent. The primary outcome was CD after attempted induction between the three study groups which included MP, DP, and PFB. Secondary outcomes included inability to achieve active labor (defined as cervical dilation of 6 cm or greater), cervical dilation at the time of CD, the incidence of CD for the indication of non-reassuring fetal status, and neonatal outcomes including Apgar scores and admission to neonatal intensive care unit. Multivariable logistic regression was performed to evaluate the association of these outcomes with MP as the induction agent versus the referent groups, PFB. Results: Of 260 inductions where the infant was found to be SGA by birth weight during the 5-year period, 172 (66.2%) patients were induced using MP, 38 (14.6%) with DP, and 50 (19.2%) with PFB. There were no differences in baseline characteristics between groups (age, race, BMI, parity, induction indication, birth weights, or maternal comorbidities). MP did not increase rate of CD which was 25.6%, 26.3%, and 22.0% in the MP, DP, and PFB groups, respectively (p = .86). There were also no differences in incidence of CD for non-reassuring fetal well-being (NRFWB), failure to attain active labor, or cervical dilation at time of CD between induction groups. NICU admission was 18%, 18%, and 16% (p = .94) between MP, DP, and PFB groups, respectively. MP was not associated with an increased rate of CD when compared with the other two agents combined, aOR 0.93 (0.67-1.30, 95% CI). Conclusion: MP appears to have similar efficacy and safety when compared with other cervical ripening agents in pregnancies complicated by SGA.

Risk of maternal, fetal and neonatal complications associated with the use of the transcervical balloon catheter in induction of labour: A systematic review

Induction of labour is one of the most frequently applied obstetrical interventions globally. Many studies have compared the use of balloon catheters with pharmacological agents. Although the safety of the balloon catheter is often mentioned, little has been written about the total spectrum of maternal and fetal morbidity associated with induction of labour using a balloon catheter. We evaluated the safety of labour induction with a transcervical balloon catheter by conducting a literature review with pooled risk assessments of the maternal, fetal and neonatal morbidity. We searched Medline, EMBASE and CINAHL as well as the Cochrane database using the Keywords 'induction of labour', 'cervical ripening', 'transcervical balloon', 'balloon catheter' and 'Foley balloon'. We did not use language or date restrictions. Randomized and quasi-randomized controlled trials as well as observational studies that contained original data on occurrence of maternal, fetal or neonatal morbidity during induction of labour with the balloon catheter were included. Studies were excluded if the balloon catheter was used concurrently with oxytocin and concurrently or consecutively with misoprostol, dinoprostone or extra-amniotic saline infusion. Study selection and quality assessment was performed by two authors independently using a standardized critical appraisal instrument. Outcomes were reported as weighted mean rates. We detected 84 articles reporting on 13,791 women. The overall risk of developing intrapartum maternal infection was 11.3% (912 of 8079 women), 3.3% (151 of 4538 women) for postpartum maternal infection and 4.6% (203 of 4460 women) for neonatal infection. Uterine hypercontractility occurred in 2.7% (148 of 5439) of the women. Uterine rupture after previous caesarean section occurred in 1.9% of women (26 of 1373), while other major maternal complications had an occurrence rate of <1%. The risk for developing minor maternal complications was <2%. The risk of developing a non-reassuring fetal heart rate was 10.8% (793 of 7336 women), 10.1% (507 of 5008 women) for fetal distress and 14.0% (460 of 3295 women) for meconium stained liquor. Neonatal death occurred in 0.29% (6 of 2058) of the deliveries and NICU admission in 7.2% (650 of 9065 deliveries). This review shows that labour induction with a balloon catheter is a safe intervention, with intrapartum maternal infection being the only reasonable risk above 10%.

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

Importance

Induction of labor is a widely used obstetric intervention, occurring in one in four pregnancies. When the cervix is unfavorable, still many different induction methods are used.

Objective

We compared Foley catheter alone to different misoprostol dosages and administration routes, and the combination of Foley catheter with misoprostol.

Evidence acquisition

We reviewed the literature on the best induction method regarding their safety and effectiveness, using the outcome measures hyperstimulation, fetal distress, neonatal morbidity and mortality as well as cesarean delivery, vaginal instrumental delivery, and maternal morbidity. We searched Pubmed, Cochrane, and Web of Science from January 1, 1980 to February 12, 2016. Twenty-two randomized controlled trials (RCTs) were included, comparing Foley catheter with or without misoprostol to misoprostol alone (both vaginal and oral) for induction of labor (5,015 women).

Results

Most included studies were underpowered to detect differences in safety outcomes, as the majority are powered for time to delivery or cesarean delivery. Meta-analysis of these studies does not allow assessment of the safety profile of Foley catheter compared to misoprostol (any dose, any administration route) with sufficient power. For the safety outcomes of the total group of Foley catheter versus misoprostol (any dose, any administration route) (17 studies, 4,234 women) we found that Foley catheter results in less hyperstimulation compared to misoprostol (2% versus 4%; risk ratio [RR], 0.54; 95% confidence interval [CI], 0.37-0.79) and fewer cesarean deliveries for nonreassuring fetal heart rate, 5% vs 7%; RR, 0.72; 95% CI, 0.55-0.95; while there were no statistically significant differences in neonatal outcomes. The total number of cesarean deliveries was 26% versus 22% (RR, 1.16; 95% CI, 1.00-1.34). There were fewer vaginal instrumental deliveries with a Foley catheter compared to misoprostol (10% vs 14%; RR, 0.74; 95% CI, 0.60-0.91). Foley catheter with misoprostol compared to misoprostol alone (any dose, any administration route) (7 studies, 1,073 women) resulted in less hyperstimulation than misoprostol alone (17% vs 23%; RR, 0.71; 95% CI, 0.52-0.97). Cesarean deliveries for nonreassuring fetal heart rate were comparable (7% vs 9%; RR, 0.79; 95% CI, 0.51-1.22). Neonatal outcomes were infrequently reported. The total number of cesarean deliveries was 34% versus 34% (RR, 1.01; 95% CI, 0.86-1.19).

Conclusion

In women with an unripe cervix at term, Foley catheter seems to have a better safety profile than misoprostol (any dose, any administration route) for induction of labor. Larger studies are needed to investigate the safety profile of a Foley catheter compared to separate dosing and administration regimens of misoprostol.