Applying Tension to the Transcervical Foley Balloon and Delivery Times in Term Nulliparous Women Undergoing Induction of Labor: A Randomized Controlled Trial

OBJECTIVE

To investigate the effects of applying tension to a transcervical Foley balloon on delivery time in term nulliparous patients undergoing labor induction.

METHODS

This cluster randomized clinical trial included 279 term nulliparous women presenting for labor induction with a plan for cervical ripening through transcervical Foley balloon placement. Participants were assigned to either the tension group (n=138) or the no-tension group (n=141) on the basis of randomized, weekly clusters (26 total clusters). The primary outcome measured was the time from initial Foley balloon insertion to delivery. Secondary outcomes included cesarean delivery rates, peripartum infection, and neonatal intensive care unit (NICU) admission. Our prior data suggested that delivery time in the tension group would be about 1,053 minutes. We estimated a sample size of 260 (130 per group, 26 clusters) on the basis of a 25% difference, power of 80%, and two-sided α of 0.05.

RESULTS

A total of 279 term nulliparous patients were included in the analysis. The median time from Foley placement to delivery was 1,596 minutes (range 430-3,438 minutes) for the tension group and 1,621 minutes (range 488-3,323 minutes) for the no-tension group ( P =.8); similar results were noted for time to vaginal delivery. No significant differences were observed in the secondary outcomes, including the rates of cesarean delivery (34.1% vs 29.8%, P =.7), peripartum infection, and NICU admission, between the two groups.

CONCLUSION

Applying tension to a transcervical Foley balloon in term nulliparous women undergoing labor induction did not significantly reduce delivery time or improve secondary outcomes.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , NCT05404776.

Interval between balloon removal and oxytocin administration in cervical ripening with double-balloon in singleton pregnancies: An observational study

OBJECTIVE

To analyze the influence of the resting interval after removal of a double-balloon for cervical ripening and oxytocin administration on the time to onset of active labor in singleton pregnancies.

METHODS

A retrospective cohort study of women who required a cervical ripening with double-balloon was conducted between January 2019 and December 2022. We collected data for cervical ripening balloon insertion and removal, oxytocin administration, suspicious or pathological cardiotocographic trace, mode of delivery, maternal and neonatal complications, neonatal outcomes. Proportional hazards model comparing resting interval between double-balloon cervical ripening removal and oxytocin administration.

RESULTS

A total of 403 singleton pregnancies were recruited and 213 pregnant women experienced a rest of 12 h between cervical balloon removal and oxytocin administration (resting group). Oxytocin was administered immediately after balloon removal in 190 women (non-resting group). Median insertion-to-active labor interval and insertion-to-delivery interval were significantly shorter in the non-resting group: 18.5 versus 24.0 h, HR 2.59 (CI 95%: 1.97-3.41) and 24.0 versus 29.0 h, HR 2.38 (CI 95%: 1.85-3.05) respectively. Bishop score change and mode of delivery between were similar in both groups. No differences in maternal nor neonatal complications between both groups were found.

CONCLUSIONS

Oxytocin administration immediately after removal of a double-balloon for cervical ripening compared with 12 h delayed interval resulted in a shortened time from insertion to active labor onset and to delivery interval without increasing maternal or neonatal adverse outcomes.

Effect of epidural analgesia on cervical ripening using dinoprostone vaginal inserts

OBJECTIVE

To clarify whether the duration from cervical ripening induction to labor onset is prolonged when epidural analgesia is administered following application of dinoprostone vaginal inserts vs. cervical ripening balloon.

METHODS

This retrospective study included mothers with singleton deliveries at a single center between 2020-2021. Nulliparous women who underwent labor induction and requested epidural analgesia during labor after 37 weeks of gestation were included. The duration from cervical ripening induction to labor onset was compared between women using a dinoprostone vaginal insert and those using a cervical ripening balloon and between women who received epidural analgesia before and after labor onset.

RESULTS

In the dinoprostone vaginal insert group, the duration was significantly shorter in the subgroup that received epidural analgesia after labor onset (estimated median, 545 [95% confidence interval: 229-861 min]) than the subgroup that received it before labor onset (estimated median, 1,570 [95% confidence interval: 1,226-1,914] min, p = 0.004). However, in the cervical ripening balloon group, the difference between subgroups was not significant. The length of labor among the groups was also not significantly different.

CONCLUSION

Epidural analgesia as labor relaxant adversely affected the progression of uterine cervical ripening when dinoprostone vaginal inserts were used, whereas it did not affect cervical ripening when a mechanical cervical dilatation balloon was used. The present results are significant for choosing the appropriate ripening method.

The effect of slow-release vaginal dinoprostone on maternal and fetal oxidative stress in term pregnancies complicated by oligohydramnios: Prospective cohort study

BACKGROUND

To evaluate changes in oxidant status using thiol/disulfide homeostasis in mothers and fetuses after induction of labor with slow-release vaginal dinoprostone inserts.

METHODS

A total of 70 pregnant women were divided into two groups. Thirty-five women in whom labor was induced with slow-release vaginal dinoprostone inserts (10 mg of prostaglandin E2, group A) were compared before and after the administration. The other 35 women, who were followed up spontaneously during labor (group B), were included as a control group. Both groups were diagnosed with isolated oligohydramnios without signs of placental insufficiency. The thiol/disulfide homeostasis parameters were calculated before medical induction and after removal of the insert at the beginning of the active phase of labor. Maternal and cord blood values were measured in both groups.

RESULTS

Although the balance shifted to the antioxidant side after the slow-release vaginal dinoprostone insert was applied, there was no significant difference in maternal oxidative load compared to the pre-application status (5.32 ± 014/5.16 ± 0.15, p = 0.491). Despite the shift toward the antioxidant side, maternal antioxidants were still significantly lower in the group that received slow-release vaginal dinoprostone at the beginning of the active phase of labor than in the control group (295.98 ± 13.03/346.47 ± 12.04, respectively, p = 0.009). There was no statistically significant difference in terms of oxidative balance or newborn Apgar score ( p > 0.05).

CONCLUSION

Induction of labor with slow-release vaginal dinoprostone inserts in pregnancies with isolated oligohydramnios does not cause further oxidative stress and is safe for both mothers and neonates in terms of oxidant load by thiol/disulfide homeostasis.

Two different regimens of outpatient Foley catheter induction of labor in nulliparas: A randomized trial

OBJECTIVES

To evaluate expectant compared to immediate return to hospital upon outpatient Foley catheter expulsion predicated on maternal satisfaction and amniotomy-titrated oxytocin infusion to delivery interval.

METHODS

This randomized trial was conducted in a tertiary university hospital in Malaysia from September 2020 to February 2022. A total of 330 nulliparous women at term with unripe cervices (Bishop score ≤5), singleton viable fetus in cephalic presentation, reassuring preinduction fetal heart rate tracing and intact membranes who underwent planned outpatient Foley catheter induction of labor (IOL) were included. Women were randomized to expectant or immediate return to hospital if the Foley was spontaneously expelled at home before their scheduled hospital admission the following day. Primary outcomes were amniotomy-titrated oxytocin infusion to delivery interval and maternal satisfaction on the induction process (assessed by 0-10 visual numerical rating scale [VNRS]).

RESULTS

Amniotomy-titrated oxytocin infusion to delivery interval was 8.7 ± 4.1 versus 8.9 ± 3.9 h, P = 0.605 (mean difference - 0.228 95% CI: -1.1 to +0.6 h) and maternal satisfaction VNRS score was median (interquartile range) 8 (7-9) versus 8 (7-9), P = 0.782. Early return to hospital rates were 37/165 (22.4%) versus 72/165 (43.6%), RR 0.51 (95% CI: 0.37-0.72), P ≤ 0.001, Cesarean delivery rates were 80/165 (48.5%) versus 80/165 (48.5%), RR 1.00 (95% CI: 0.80-1.25), P = 1.00 and duration of hospital stay was 54.4 ± 22.9 versus 56.7 ± 22.8 h, P = 0.364 for the expectant versus immediate return groups respectively.

CONCLUSION

In outpatient Foley catheter IOL, expectant compared to immediate return to hospital following Foley dislodgement results in similarly high maternal satisfaction. The amniotomy-titrated oxytocin to delivery duration is non-inferior with expectant management.

Just Pop It: Early AROM After Cervical Ripening Reduces the Time to Delivery

In pregnant patients at term undergoing induction of labor, early time-based artificial rupture of membranes (AROM) within 1 hour of Foley bulb expulsion results in a shorter duration of labor by nearly 9 hours with no significant difference in cesarean delivery rates or maternal or neonatal adverse outcomes.1.

Outpatient cervical ripening and labor induction with low-dose vaginal misoprostol reduces the interval to delivery: a systematic review and network meta-analysis

OBJECTIVE

Several systematic reviews and meta-analyses have summarized the evidence on the efficacy and safety of various outpatient cervical ripening methods. However, the method with the highest efficacy and safety profile has not been determined conclusively. We performed a systematic review and network meta-analysis of published randomized controlled trials to assess the efficacy and safety of cervical ripening methods currently employed in the outpatient setting.

DATA SOURCES

With the assistance of an experienced medical librarian, we performed a systematic search of the literature using MEDLINE, Embase, Scopus, Web of Science, Cochrane Library, and ClinicalTrials.gov. We systematically searched electronic databases from inception to January 14, 2020.

STUDY ELIGIBILITY CRITERIA

We considered randomized controlled trials comparing a variety of methods for outpatient cervical ripening.

METHODS

We conducted a frequentist random effects network meta-analysis employing data from randomized controlled trials. We performed a direct, pairwise meta-analysis to compare the efficacy of various outpatient cervical ripening methods, including placebo. We employed ranking strategies to determine the most efficacious method using the surface under the cumulative ranking curve; a higher surface under the cumulative ranking curve value implied a more efficacious method. We assessed the following outcomes: time from intervention to delivery, cesarean delivery rates, changes in the Bishop score, need for additional ripening methods, incidence of Apgar scores <7 at 5 minutes, and uterine hyperstimulation.

RESULTS

We included data from 42 randomized controlled trials including 6093 participants. When assessing the efficacy of all methods, 25 μg vaginal misoprostol was the most efficacious in reducing the time from intervention to delivery (surface under the cumulative ranking curve of 1.0) without increasing the odds of cesarean delivery, the need for additional ripening methods, the incidence of a low Apgar score, or uterine hyperstimulation. Acupressure (surface under the cumulative ranking curve of 0.3) and primrose oil (surface under the cumulative ranking curve of 0.2) were the least effective methods in reducing the time to delivery interval. Among effective methods, 50 mg oral mifepristone was associated with the lowest odds of cesarean delivery (surface under the cumulative ranking curve of 0.9).

CONCLUSION

When balancing efficacy and safety, vaginal misoprostol 25 μg represents the best method for outpatient cervical ripening.

Tafoxiparin, a novel drug candidate for cervical ripening and labor augmentation: results from 2 randomized, placebo-controlled studies

BACKGROUND

Slow progression of labor is a common obstetrical problem with multiple associated complications. Tafoxiparin is a depolymerized form of heparin with a molecular structure that eliminates the anticoagulant effects of heparin. We report on 2 phase II clinical studies of tafoxiparin in primiparas. Study 1 was an exploratory, first-in-pregnant-women study and study 2 was a dose-finding study.

OBJECTIVE

Study 1 was performed to explore the effects on labor time of subcutaneous administration of tafoxiparin before onset of labor. Study 2 was performed to test the hypothesis that intravenous treatment with tafoxiparin reduces the risk for prolonged labor after spontaneous labor onset in situations requiring oxytocin stimulation because of dystocia.

STUDY DESIGN

Both studies were randomized, double-blind, and placebo-controlled. Participants were healthy, nulliparous females aged 18 to 45 years with a normal singleton pregnancy and gestational age confirmed by ultrasound. The primary endpoints were time from onset of established labor (cervical dilation of 4 cm) until delivery (study 1) and time from start of study treatment infusion until delivery (study 2). In study 1, patients at 38 to 40 weeks of gestation received 60 mg tafoxiparin or placebo daily as 0.4 mL subcutaneous injections until labor onset (maximum 28 days). In study 2, patients experiencing slow progression of labor, a prolonged latent phase, or labor arrest received a placebo or 1 of 3 short-term tafoxiparin regimens (initial bolus 7, 21, or 35 mg followed by continuous infusion at 5, 15, or 25 mg/hour until delivery; maximum duration, 36 hours) in conjunction with oxytocin.

RESULTS

The number of participants randomized in study 1 was 263, and 361 were randomized in study 2. There were no statistically significant differences in the primary endpoints between those receiving tafoxiparin and those receiving the placebo in both studies. However, in study 1, the risk for having a labor time exceeding 12 hours was significantly reduced by tafoxiparin (tafoxiparin 6/114 [5%] vs placebo 18/101 [18%]; P=.0045). Post hoc analyses showed that women who underwent labor induction had a median (range) labor time of 4.44 (1.2-8.5) hours with tafoxiparin and 7.03 (1.5-14.3) hours with the placebo (P=.0041) and that co-administration of tafoxiparin potentiates the effect of oxytocin and facilitates a shorter labor time among women with a labor time exceeding 6 to 8 hours (P=.016). Among women induced into labor, tafoxiparin had a positive effect on cervical ripening in 11 of 13 cases (85%) compared with 3 of 13 participants (23%) who received the placebo (P=.004). For women requiring oxytocin because of slow progression of labor, the corresponding results were 34 of 51 participants (66%) vs 16 of 40 participants (40%) (P=.004). In study 2, tafoxiparin had no positive effects on the secondary endpoints when compared with the placebo. Except for injection-site reactions in study 1, adverse events were no more common for tafoxiparin than for the placebo among either mothers or infants. There were few serious or treatment-related adverse events.

CONCLUSION

Subcutaneous treatment with tafoxiparin before labor onset (study 1) may be effective in reducing the labor time among women undergoing labor induction and among those requiring oxytocin for slow progression of labor. Moreover, tafoxiparin may have a positive effect on cervical ripening. Short-term, intravenous treatment with tafoxiparin as an adjunct to oxytocin in patients with labor arrest (study 2) did not affect labor time or other endpoints. Both studies suggest that tafoxiparin has a favorable safety profile in mothers and their infants.

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.

Methods of induction of labor in women with obesity: A secondary analysis of two multicenter randomized controlled trials

INTRODUCTION

Obesity is an increasing public health concern worldwide and can lead to more complications in pregnancy and childbirth. Women with obesity more often require induction of labor for various indications. The aim of this study is to assess which method of induction of labor is safest and most effective in women with obesity.

MATERIAL AND METHODS

This is a secondary analysis of two randomized controlled trials about induction of labor. Women with a term singleton pregnancy in cephalic presentation, an unfavorable cervix, intact membranes and without a previous cesarean section were randomly allocated to cervical priming with a Foley catheter or vaginal prostaglandin-E2-gel (PROBAAT-I) or a Foley catheter or oral misoprostol (PROBAAT-II). The inclusion and exclusion criteria for the studies were identical. Induction methods were compared in women with obesity (body mass index ≥30.0). Main outcomes were cesarean section and postpartum hemorrhage (blood loss >1000 mL).

RESULTS

A total of 2664 women, were included in the trials, 517 of whom were obese: 254 women with obesity received a Foley catheter, 176 oral misoprostol and 87 prostaglandin E2 (PGE2). A cesarean section was performed in 29.1% of women allocated to Foley vs 22.2% in the misoprostol and 23.0% in the PGE2 groups. Comparisons between groups revealed no statistically significant differences: the relative risk [RR] was 1.31 (95% confidence interval [CI] 0.94-1.84) in the Foley vs misoprostol group and 1.27 (95% CI 0.83-1.95) in the Foley vs PGE2 group. The rates of postpartum hemorrhage were comparable (10.6%, 11.4% and 6.9%, respectively; P = 0.512). In women with obesity, more often a switch to another method occurred in the Foley group, (20.1% vs 6.3% in misoprostol vs 1.1% in the PGE2 group; P < 0.001). The risk of a failed Foley placement was higher in women with obesity than in women without obesity (8.3% vs 3.2%; adjusted odds ratio 3.12, 95% CI 1.65-5.90).

CONCLUSIONS

In women with obesity we found a nonsignificant trend towards an increased rate of cesarean sections in the group induced with a Foley catheter compared to oral misoprostol; however, the study lacked power for this subgroup analysis. The finding of a higher risk of failed placement of a Foley catheter in women with obesity can be used in shared decision making.

The efficacy and safety of 25 μg or 50 μg oral misoprostol versus 25 μg vaginal misoprostol given at 4- or 6-hourly intervals for induction of labour in women at or beyond term with live singleton pregnancies: A systematic review and meta-analysis

BACKGROUND

Misoprostol is widely used for cervical ripening and labour induction as it is heat-stable and inexpensive. Oral misoprostol 25 μg given 2-hourly is recommended over vaginal misoprostol 25 μg given 6-hourly, but the need for 2-hourly fetal monitoring makes oral misoprostol impractical for routine use in high-volume obstetric units in resource-constrained settings.

OBJECTIVES

To compare the efficacy and safety of oral misoprostol initiated at 25 or 50 μg versus 25 μg vaginal misoprostol given at 4- to 6-hourly intervals for labor induction in women at or beyond term (≥ 37 weeks) with a single viable fetus and an unscarred uterus.

SEARCH STRATEGY

We identified eligible randomized, parallel-group, labor-induction trials from recent systematic reviews. We additionally searched PubMed, Cochrane CENTRAL, Epistemonikos, and clinical trials registries from February 1, 2020 to December 31, 2022 without language restrictions. Database-specific keywords for cervical priming, labor induction, and misoprostol were used.

SELECTION CRITERIA

We excluded labor-induction trials exclusively in women with ruptured membranes, in the third trimester, and those that initiated misoprostol at doses not specified in the review's objectives. The primary outcomes were vaginal birth within 24 h, cesarean section, perinatal mortality, neonatal morbidity, and maternal morbidity. The secondary outcomes were uterine hyperstimulation with fetal heart rate changes, and oxytocin augmentation.

DATA COLLECTION AND ANALYSIS

Two or more authors selected studies independently, assessed risk of bias, and extracted data. We derived pooled weighted risk ratios with 95% confidence intervals (CIs) for each outcome, subgrouping trials by the dose and frequency of misoprostol regimens. We used the I2 statistic to quantify heterogeneity and the random-effects model for meta-analysis when appropriate. We used the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach to assess certainty (confidence) in the effect estimates.

MAIN RESULTS

Thirteen trials, from Canada, India, Iran, and the US, randomizing 2941 women at ≥37 weeks of gestation with an unfavorable cervix (Bishop score <6), met the eligibility criteria. Five misoprostol regimens were compared: 25 μg oral versus 25 μg vaginal, 4-hourly (three trials); 50 μg oral versus 25 μg vaginal, 4-hourly (five trials); 50 μg followed by 100 μg oral versus 25 μg vaginal, 4-hourly (two trials); 50 μg oral, 4-hourly versus 25 μg vaginal, 6-hourly (one trial); and 50 μg oral versus 25 μg vaginal, 6-hourly (two trials). The overall certainty in the evidence ranged from moderate to very low, due to high risk of bias in 11/13 trials (affecting all outcomes), unexplained heterogeneity (1/7 outcomes), indirectness (1/7 outcomes), and imprecision (4/7 outcomes). Vaginal misoprostol probably increased vaginal deliveries within 24 h compared with oral misoprostol (risk ratio [RR] 0.82, 95% CI 0.70-0.96; 11 trials, 2721 mothers; moderate-certainty evidence); this was more likely with 4-hourly than with 6-hourly vaginal regimens. The risk of cesarean sections did not appreciably differ (RR 1.00, 95% CI 0.80-1.26; 13 trials, 2941 mothers; very low-certainty evidence), although oral misoprostol 25 μg 4-hourly probably increased this risk compared with 25 μg vaginal misoprostol 4-hourly (RR 1.69, 95% CI 1.21-2.36; three trials, 515 mothers). The risk of perinatal mortality (RR 0.67, 95% CI 0.11-3.90; one trial, 196 participants; very low-certainty evidence), neonatal morbidity (RR 0.84, 95% CI 0.67-1.06; 13 trials, 2941 mothers; low-certainty evidence), and maternal morbidity (RR 0.83, 95% CI 0.48-1.44; 6 trials; 1945 mothers; moderate-certainty evidence) did not differ appreciably. The risk of uterine hyperstimulation with fetal heart rate changes may be lower with oral misoprostol (RR 0.70, 95% CI 0.52-0.95; 10 trials, 2565 mothers; low-certainty evidence). Oxytocin augmentation was probably more frequent with oral compared with vaginal misoprostol (RR 1.29, 95% CI 1.10-1.51; 13 trials, 2941 mothers; moderate-certainty evidence).

CONCLUSIONS

Low-dose, 4- to 6-hourly vaginal misoprostol regimens probably result in more vaginal births within 24 h and less frequent oxytocin use compared with low-dose, 4- to 6-hourly, oral misoprostol regimens. Vaginal misoprostol may increase the risk of uterine hyperstimulation with fetal heart changes compared with oral misoprostol, without increasing the risk of perinatal mortality, neonatal morbidity, or maternal morbidity. Indirect evidence indicates that 25 μg vaginal misoprostol 4-hourly may be more effective and as safe as the recommended 6-hourly vaginal regimen. This evidence could inform clinical decisions in high-volume obstetric units in resource-constrained settings.

[Comparison of vaginal prostaglandins with oral misoprostol as a second line of cervical ripening after using a cervical balloon catheter]

OBJECTIVE

To compare vaginal prostaglandins with oral misoprostol as a second line of cervical ripening after using a cervical balloon catheter.

MATERIAL AND METHODS

This is a retrospective monocentric study (Lille, France), according to a "before"/"after" design. The inclusion criteria were a singleton pregnancy, with a fetus in cephalic presentation, a term >37 WA, with a cervix having a Bishop score lower than 6 after a first line of maturation by cervical balloon catheter. Two groups were formed: "before" corresponding to the continuation of maturation by vaginal prostaglandins, from March 2019 to November 2019, and "after": corresponding to the continuation of maturation by oral misoprostol, from June 2020 to December 2020. The primary outcome was vaginal delivery rate.

RESULTS

One hundred women were included in each group. The rate of vaginal delivery was similar between the 2 groups (76% vs 81%, p=0.39), as were the times between the start of induction and the birth and between the start of induction and the transition to birth room. There was no difference in the indication for caesarean section, with in particular an identical rate of caesarean sections for induction failure (p=0.52). Subgroup analysis in obese women showed a significantly higher rate of vaginal delivery in the "after" group (OR=4.17;95% CI [1.02;17.07]).

CONCLUSION

The vaginal delivery rate is similar when using vaginal prostaglandins or oral misoprostol as second line cervical ripening after use of a cervical balloon catheter.

Vaginal Compared With Oral Misoprostol Induction at Term: A Cluster Randomized Controlled Trial

OBJECTIVE

To evaluate efficacy in achieving vaginal delivery with a standardized vaginal compared with oral misoprostol regimen for labor induction at term.

METHODS

In this single-center, cluster randomized trial, we randomized induction method by week among individuals with gestational age of 37 weeks or more, cervical dilation of 2 cm or less, intact membranes, and indication for delivery to either oral (100 micrograms every 4 hours for up to two doses), or vaginal (25 micrograms every 3 hours for up to five doses) misoprostol regimens, followed by a standardized oxytocin protocol. Individuals with an antepartum stillbirth, major fetal anomalies, malpresentation, ruptured membranes, nonreassuring fetal status, or contraindication to prostaglandin were excluded. The primary outcome was vaginal delivery at first induction attempt. Secondary outcomes included time to delivery, need for oxytocin, chorioamnionitis, and adverse maternal and neonatal outcomes. Outcomes were recorded at the individual level and adjusted for clustering, with analysis by intention to treat.

RESULTS

Between May 24, 2021, to September 19, 2022, 1,322 women were randomized to vaginal misoprostol in 33 clusters and 1,224 to oral misoprostol in 37 clusters. Demographic characteristics or initial cervical dilation did not differ between groups. The primary outcome did not differ between induction regimens and occurred in 1,032 (78.1%) of the vaginal misoprostol arm and 945 (77.2%) of the oral misoprostol arm (adjusted relative risk [RR] 1.01, 95% CI, 0.97-1.05). Tachysystole with fetal heart rate changes occurred less frequently with vaginal compared with oral misoprostol (3.5% vs 5.9%, adjusted RR 0.59, 95% CI, 0.40-0.87). Time to delivery did not differ between groups. Oxytocin was less frequently required before delivery in the vaginal misoprostol group (68.8% vs 78.4%, adjusted RR 0.88, 95% CI, 0.84-0.92).

CONCLUSION

Induction of labor with vaginal compared with oral misoprostol protocols did not increase the frequency of vaginal delivery at term but did reduce the need for oxytocin use before delivery.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT04755218.

Time from insertion to expulsion of cervical ripening balloon in preterm versus term inductions of labor

OBJECTIVE

Preterm induction of labor can be necessary for maternal and fetal wellbeing. Duration of cervical ripening balloon (CRB) use has been studied in only term inductions. Our study investigated duration of time in hours for CRB expulsion and vaginal delivery in preterm inductions of labor.

METHODS

This was a single-institution retrospective cohort study of preterm (< 37 weeks) and term (≥ 37 weeks) inductions with CRB between 2010 and 2021. Cesarean deliveries were excluded. Primary outcome was insertion to expulsion time of CRB. Secondary outcomes included induction to delivery time, cervical dilation after expulsion, misoprostol, and Pitocin use. Institutional review board (IRB) approval was obtained prior to the study.

RESULTS

Ninety-eight patients with vaginal delivery after preterm CRB use were identified and matched 1:1 on baseline characteristics (p > 0.05) to term patients with vaginal delivery after CRB use. Mean insertion to expulsion time was significantly shorter for term than preterm inductions (mean 7.2 ± 3.09 h versus 8.5 ± 3.38 h; p < 0.01). Mean induction to delivery time was significantly shorter for term than preterm inductions (18.4 ± 7.6 h versus 22.5 ± 9.01 h; p < 0.01). Increased use of misoprostol, Pitocin, and second CRB were noted among the preterm cohort. Among term patients, more CRB placement at start of induction and greater cervical dilation post-balloon were found in comparison to preterm patients.

CONCLUSION

Among patients undergoing preterm induction, longer insertion to expulsion time of CRB, longer induction to delivery time, and increased interventions should be expected. Different standards for labor management should be considered for achieving vaginal delivery in preterm inductions.

The association between maternal colonization with Group B Streptococcus and infectious morbidity following transcervical Foley catheter-assisted labor induction

OBJECTIVES

To determine whether maternal colonization with Group B Streptococcus increases the risk for infectious morbidity following transcervical Foley catheter-assisted cervical ripening.

METHODS

A retrospective cohort study comparing infectious morbidity and other clinical outcomes by Group B Streptococcus colonization status between all women with singleton pregnancies who underwent Foley catheter-assisted cervical ripening labor induction at a single tertiary medical center during 2011-2021. Multivariable logistic regression explored the relationship between Group B Streptococcus colonization to adverse outcomes while adjusting for relevant clinical variables.

RESULTS

A total of 4,409 women were included of whom 886 (20.1 %) were considered Group B Streptococcus carriers and 3,523 (79.9 %) were not. Suspected neonatal sepsis rate was similar between Group B Streptococcus carriers and non-carriers (5.2 vs. 5.0 %, respectively, p=0.78). Neonatal sepsis was confirmed in 7 (0.02 %) cases, all born to non-carriers. Group B Streptococcus carriers had a higher rate of maternal bacteremia compared to non-carriers (1.2 vs. 0.5 %, respectively, p=0.01). Group B Streptococcus colonization was independently associated with maternal bacteremia (adjusted odds ratio 3.05; 95 %CI 1.39, 6.66).

CONCLUSIONS

Group B Streptococcus colonization among women undergoing Foley catheter-assisted cervical ripening does not seem to increase the risk for neonatal infection. However, higher rates of maternal bacteremia were detected.

[Clinical analysis of 102 cases of labor induction in the third trimester on twin pregnancy]

Objective: To investigate the clinical characteristics of induced labor in twin pregnancy and the related factors of induced labor failure. Methods: The clinical data of twin pregnant women who underwent induced labor in Peking University Third Hospital from January 2016 to December 2022 were retrospectively analyzed. According to whether they had labor or not after induction, pregnant women were divided into the success group (pregnant women who had labor after induction, 72 cases) and the failure group (pregnant women who did not have labor after induction, 30 cases). Logistic regression was used to analyze the related factors of induction failure in twin pregnant women. Results: The parity and cervical Bishop score in the failure group were significantly lower than those in the success group, while the proportion of dichorionic diamniotic twins, assisted reproductive technology pregnancy and cervical Bishop score <6, postpartum hospital stay and total hospital stay in the failure group were significantly higher than those in the success group (all P<0.05). The proportion of induced labor by artificial rupture of membranes ± oxytocin intravenous infusion in the success group was 72.2% (52/72), which was significantly higher than that in the failure group (46.7%, 14/30; P=0.030). There were no significant differences between the two groups in the gestational age at delivery, the incidence of severe postpartum hemorrhage and blood transfusion, the amount of postpartum hemorrhage, the neonatal weight of two fetuses, the incidence of neonatal asphyxia, and the proportion of neonates admitted to the neonatal intensive care unit (all P>0.05). There were no severe perineal laceration and hysterectomy in all pregnant women. Multivariate logistic regression analysis showed that primipara (OR=3.064, 95%CI: 1.112-8.443; P=0.030) and cervical Bishop score <6 (OR=5.208, 95%CI: 2.008-13.508; P=0.001) were the independent risk factors for induction failure in twin pregnancy. Conclusions: Elective induction of labor in twin pregnancy is safe and feasible. It is helpful to improve the success rate of induction of labor by strictly grasping the timing and indications of termination of pregnancy, choosing the appropriate method of induction according to the condition of the cervix, and actively promoting cervical ripening.

The use of virtual reality during extra-amniotic balloon insertion for pain and anxiety relief-a randomized controlled trial

BACKGROUND

Induction of labor with an extra-amniotic balloon catheter is a procedure commonly associated with maternal discomfort, pain, and anxiety.

OBJECTIVE

We aimed to investigate the distractive effect of virtual reality technology on pain and anxiety among pregnant patients who underwent induction of labor with an extra-amniotic balloon catheter.

STUDY DESIGN

In this randomized controlled trial, pregnant patients who were undergoing planned induction of labor using an extra-amniotic balloon catheter at term for various obstetrical indications were recruited and randomized in a 1:1 ratio into 2 groups. Patients in the virtual reality group were exposed to a virtual reality technology clip (using SootheVR All-In-One virtual reality care system for pain and anxiety) during the entire extra-amniotic balloon catheter insertion, whereas patients in the control group received the institutional standard care for extra-amniotic balloon catheter insertion. Pain scores, expressed as visual analog scale scores, and maternal hemodynamic parameters were obtained before, during, and after extra-amniotic balloon catheter insertion. Anxiety was evaluated using the validated State-Trait Anxiety Inventory Scale before and after the procedure. Maternal satisfaction with the virtual reality technology was also recorded. The primary outcome was the change in visual analog scale score before and during extra-amniotic balloon catheter insertion. Among the secondary outcomes was the change in anxiety levels before and after extra-amniotic balloon catheter insertion. The study was powered to detect a 25% decrease in the primary outcome.

RESULTS

A total of 132 pregnant patients were recruited (66 in each group). There were no differences between groups in terms of age, body mass index, gestational age at enrollment, indication for induction of labor, and preprocedural visual analog scale score and anxiety levels. The change in visual analog scale score (maximal visual analog scale score during the procedure minus the initial visual analog scale score before the procedure, ie, the primary outcome) was significantly lower in the virtual reality group than in the control group (2.78±3.0 vs 4.09±2.99; P=.01). In addition, the virtual reality group experienced a higher rate of anxiety relief, expressed as the difference between the preprocedure and postprocedure State-Trait Anxiety Inventory Scale scores (-6.46±9.6 vs -2.01±9.11; P=.007). Patients in the virtual reality group reported a very high overall (94%) satisfaction score.

CONCLUSION

In this randomized controlled trial, we demonstrated that the use of virtual reality technology among patients who underwent induction of labor using an extra-amniotic balloon catheter was associated with lower visual analog scale scores during the procedure and a significant reduction in anxiety than patients who received standard care. There was also a very high satisfaction rate with the use of virtual reality technology.

Association of the key immunological and hemodynamic determinants with cervix ripening in pregnant women

OBJECTIVE

Aim: To investigate a correlation between cervical ripening, the immunological features and the hemodynamic characteristics of the cervix during the preparation for vaginal labor.

PATIENTS AND METHODS

Materials and Methods: We examined 75 pregnant women at different gestational age. General clinical and immunological studies were conducted in order to check serum concentration of cytokines IL-6, IL-1β, and TNF-α. Ultrasound and Doppler study were used to determine resistance index and systolic-diastolic ratio of blood flow in the common uterine artery as well as the descending and ascending parts and cervical stromal arteries.

RESULTS

Results: Pregnant women with high cervical ripening score had high concentrations of the major proinflammatory cytokines (IL-1β, IL-6, and TNF-α). Analysis of the of the cervical blood flow indicators of the studied groups showed significant differences in the indices of vascular resistance in the vessels that feed the cervix. Our data showed a significant correlation between the cervix ripening and both the serum levels of the studied cytokines and the level of peripheral vascular resistance indices in the common uterine arteries of the cervix, and the blood flow indices in the cervical stromal vessels.

CONCLUSION

Conclusions: Our study shows that the process of preparing the woman's body for labor is associated with immunological adjustment and increased hemodynamics of the cervix. We report that cervical ripening is associated with the immunological components and hemodynamic parameters of the cervix at late-stage pregnancy. Measuring cervix ripening and the accompanied changes in cytokine levels and hemodynamic parameters will form a more accurate assessment of birth preparedness and labor complications.

A case study on using an intrauterine foley catheter to reduce postpartum bleeding in a patient with hemophilia

Case of a pregnant patient suffering from severe hemophilia A who had effective uterine foley tamponade to treat postpartum hemorrhage.

Optimal cervical-ripening method for labor induction in Japan after the era of controlled-release dinoprostone vaginal insert

OBJECTIVE

To investigate the predictive value of obstetric findings when using dinoprostone (prostaglandin E2 [PGE2]) vaginal inserts for cervical ripening, and to assess the optimal cervical-ripening method between PGE2 vaginal insert and/or cervical dilators.

METHODS

This prospective observational study enrolled pregnant women who underwent cervical ripening for labor induction in 37-41 week' gestation in 2020. In evaluation 1, optimal obstetric findings predictive of rapid cervical ripening using PGE2 were assessed. In evaluation 2, the duration from PGE2 administration to labor onset and perinatal outcomes were compared between cases in which only PGE2 was used and cases that were treated with PGE2 after mechanical cervical dilators (Dilapan®) for extremely immature cervical ripening (uterine cervical os <2 cm).

RESULTS

In evaluation 1, uterine dilatation before the use of a PGE2 vaginal insert was mostly correlated with the time from PGE2 administration to labor onset (r = -0.428, p < 0.001). When the uterine cervical os dilatation was ≥2 cm, a shorter time-to-labor onset was found. In addition, os dilatation, effacement, and station at the time of PGE2 vaginal insert removal also significantly progressed. In evaluation 2, the median duration from PGE2 administration to labor onset was 1740 min in cases where only PGE2 was used, and 610 min in those where PGE2 was used after mechanical cervical dilators (p = 0.011).

CONCLUSION

PGE2 vaginal inserts are relatively effective when the uterine cervical os is ≥2 cm in diameter. However, in cases of extremely immature cervical-ripening, it was feasible to use PGE2 vaginal inserts before mechanical cervical dilatation.

Evidence Based Management of Labor

Importance

Induction of labor (IOL) is a common obstetric intervention. Augmentation of labor and active management of the second stage is frequently required in obstetric practice. However, techniques around labor and induction management vary widely. Evidence-based practice regarding induction and labor management can reduce birth complications such as infection and hemorrhage and decrease rates of cesarean delivery.

Objective

To review existing evidence on IOL and labor management strategies with respect to preparing for induction, cervical ripening, induction and augmentation, and second stage of labor techniques.

Evidence acquisition

Review of recent original research, review articles, and guidelines on IOL using PubMed (2000-2022).

Results

Preinduction, pelvic floor training and perineal massage reduce postpartum urinary incontinence and perineal trauma, respectively. Timely membrane sweeping (38 weeks) can promote spontaneous labor and prevent postterm inductions. Outpatient Foley bulb placement in low-risk nulliparous patients with planned IOL reduces time to delivery. Inpatient Foley bulb use beyond 6 to 12 hours shows no benefit. When synthetic prostaglandins are indicated, vaginal misoprostol should be preferred. For nulliparous patients and those with obesity, oxytocin should be titrated using a high-dose protocol. Once cervical dilation is complete, pushing should begin immediately. Warm compresses and perineal massage decrease risk of perineal trauma.

Conclusion and relevance

Several strategies exist to assist in successful IOL and promote vaginal delivery. Evidence-based strategies should be used to improve outcomes and decrease risk of complications and cesarean delivery. Recommendations should be shared across interdisciplinary team members, creating a model that promotes safe patient care.

Twice-daily versus once-daily vaginal dinoprostone gel for induction of labor at term: A randomized controlled trial

OBJECTIVE

The aim of this study was to compare twice-daily versus once-daily administration of intravaginal PGE2 for induction of labor at term. Efficacy, safety, and patient satisfaction were evaluated.

STUDY DESIGN

For this single-center, randomized, comparative, open-label, two-arm, and parallel study, pregnant women with term singleton live pregnancies ≥ 37 weeks of gestation, medical indications for induction of labor, and Bishop score ≤ 6 were randomized to either the control group (induction of labor with PGE2 gel with repeat dose after 24 h) or the experimental group (repeat dose after 12 h). The primary outcome was induction-to-delivery interval time. Secondary outcomes were maternal and neonatal outcomes and patient satisfaction.

RESULTS

In total, 246 women were randomized to the control (n = 121) or experimental groups (n = 125). The mean time for initiation of induction to delivery was 9.4 h shorter in the experimental group compared to controls (p = 0.007). For control vs experimental, there were no differences in tachysystole (19/121, 15.7 % vs 21/124, 16.9 %, respectively; p = 0.79), cesarean section rate (18/121, 14.9 % vs 28/124, 22.6 % respectively; p = 0.12), or other main obstetrical or neonatal outcomes. Patients in the experimental group reported higher satisfaction with their induction (48/96, 50 % with once-daily vs 60/86, 69.8 % with twice-daily; p = 0.010).

CONCLUSION

Among women admitted for induction of labor at term, closer interval of vaginal PGE2 administration was associated with a significantly shorter induction-to-delivery time without increasing maternal or neonatal morbidity. Furthermore, the reduction in induction time was associated with improved patient experience of delivery.

Comparison of cesarean delivery rates after 3 methods of cervical ripening among obese women at or after 41 weeks - Secondary analysis of two French randomized controlled trials: MAGPOP and CYTOPRO

OBJECTIVE

To compare cesarean rates and maternal and neonatal morbidity according to the cervical ripening method used among obese pregnant women requiring induction of labor at or after 41 weeks of gestation.

DESIGN

A secondary analysis of two multicenter randomized controlled trials conducted in French maternity units between 2015 and 2018.

PARTICIPANTS

336 women with a body mass index ≥30 kg/m2, a pregnancy ≥41 weeks, and an induction of labor requiring cervical ripening.

INTERVENTIONS

Cervical ripening with a PGE2 dinoprostone pessary (Propess®), or low-dose vaginal PGE1 (misoprostol) or a double-balloon catheter.

MEASUREMENTS AND FINDINGS

The rates of cesarean delivery did not differ significantly according to the cervical ripening method (PGE2 pessary vs PGE1, RR: 1.18, 95% CI: 0.80-1.75; PGE2 pessary vs double balloon catheter: RR, 0.88, 95% CI: 0.60-1.29), p = 0.52; double balloon catheter vs PGE1, RR: 1.34, 95% CI: 0.77-2.32, p = 0.29). More oxytocin was required for women from the double-balloon group compared to those from both the PGE1 and PGE2 pessary groups (respectively, RR: 1.31, 95% CI: 1.08-1.58, p = 0.005; RR: 1.17, 95% CI: 1.03-1.32, p = 0.01). The risk of perineal tears or episiotomy was significantly lower for women induced with the PGE2 pessary than with PGE1 (0.85; 95% CI: 0.74-0.99), p = 0.03).

KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

No cervical ripening method was associated with a lower cesarean rate in obese women who required cervical ripening from 41 weeks. Further trials are required among obese women to determine the cervical ripening method most efficacious for reducing the cesarean rate.

Accidental rupture of membranes and neonatal infection after labor induction with silicone or latex balloon catheters: A retrospective cohort study

OBJECTIVE(S)

Accidental rupture of membranes (acROM), an insertion-related complication of the balloon catheter for labor induction, may prolong the duration of ruptured membranes. Prolonged rupture of membranes is associated with an increased risk of intra-uterine infection with possibly neonatal infection as result. Little is known about safety profiles of different catheters regarding the occurrence of these complications. This study compares the incidence of neonatal early-onset sepsis (EOS) and acROM in women receiving either silicone or latex balloon catheters.

STUDY DESIGN

A retrospective cohort study was performed including 2200 women (silicone balloon catheter, n = 1100 vs. latex balloon catheter, n = 1100). The primary outcomes were the incidence of acROM, and suspected and proven neonatal EOS. Secondary outcomes were: prolonged rupture of membranes, intrapartum fever, pre- or postnatal neonatal exposure to antibiotics, and perinatal outcomes. A subgroup analysis was performed between women with and without acROM.

RESULTS

No statistically significant difference with regard to suspected or proven EOS was seen between the silicone and latex groups. The acROM rate was significantly higher in the silicone group compared to the latex group (2.9 % and 0.3 %, p < 0.01). Prolonged rupture of membranes was significantly more common in the silicone group compared to the latex group (5.0 % and 2.4 %, p < 0.01), as was the use of intrapartum antibiotics (12.7 % and 9.6 %, p = 0.02). Neonates were significantly more often exposed to pre- or postnatal antibiotics in the silicone group compared to the latex group (17.6 % and 13.6 %, p = 0.01). Subgroup analysis showed significantly more suspected and proven neonatal EOS when catheter-insertion was complicated with acROM (11.4 % and 20.0 %), compared to cases without acROM (3.8 % and 2.5 %), irrespective of the type of catheter used.

CONCLUSION(S)

The use of silicone balloon catheters for labor induction results in higher rates of acROM, prolonged rupture of membranes and use of intrapartum antibiotics, compared to latex balloon catheters. No statistically significant differences were found in the occurrence of suspected or proven neonatal EOS, however neonates from the silicone group were more often exposed to pre- or postnatal antibiotics. When acROM occurs, irrespective of type of catheter used, suspected and proven neonatal EOS was seen more often.

Pre-cervical ripening and hygroscopic cervical dilators in pre-labor induction

INTRODUCTION

Induction of labor (IOL) is becoming a universal topic in Obstetrics, when the risk of continuing a pregnancy outweighs the benefits. Preinduction is a more recent tool to prepare the cervix when the BISHOP-score is low. About one-third of IOL cases require cervical ripening, which is the physical softening, thinning, and dilation of the cervix in preparation for labor and birth. We report a single center experience regarding the use of hygroscopic dilators in the pre-labor phase to obtain cervical ripening before labor induction.

MATERIALS & METHODS

We conducted a retrospective observational study comparing patient records from the Gynecology and Obstetrics Unit in "Santo Stefano" Hospital in Prato, Tuscany. The inclusion criteria for participants were women who had undergone pre-labor induction because of a BISHOP-score < 3. The gestational age of all the pregnant women was at term (> 37 weeks).

RESULTS

From January 2022 to April 2022, a total of 581 women delivered at term of gestational age at the Gynecology and Obstetrics Unit in "Santo Stefano" Hospital. Cervical ripening was necessary for 82 women with a Bishop score < 3 and hygroscopic cervical dilators were used in 35/82 (42.7%) patients. All patients showed a change in Bishop-score upon removal of the dilators. All 35 patients (100%) reported an increase in terms of consistency and dilation of the cervix but not in terms of length. None of the patients reported discomfort during the 24 h that they kept the hygroscopic dilators in place. No patients reported uterine tachysystole on cardiotocographic tracing, vaginal bleeding, rupture of membranes or cervical tears.

CONCLUSIONS

Our results are in line with those in the literature, demonstrating the validity of hygroscopic dilators in cervical maturation of pregnancies at term and their efficacy was again highlighted in terms of both maternal and fetal safety and patient satisfaction.

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.

Continuous vs intermittent induction of labor with oxytocin in nulliparous patients: a randomized controlled trial

BACKGROUND

Oxytocin is considered the drug of choice for the induction of labor, although the optimal protocol and infusion duration remain to be determined.

OBJECTIVE

This study aimed to assess whether the duration of oxytocin infusion increases 24-hour delivery rates and affects the length of time-to-delivery and patient's experience.

STUDY DESIGN

A randomized controlled trial was performed at a single tertiary medical center, between January 1, 2020 and June 30, 2022. Nulliparous patients with a singleton pregnancy at a vertex presentation and a Bishop score ≥6 were randomly assigned to receive either continuous (16 hours, with a 4 hours pause in between infusions) or intermittent (8 hours, with a 4 hours pause in between infusions) oxytocin infusion, until delivery. In both groups, infusion was halted when signs of maternal or fetal compromise were observed. Randomization was conducted with a computer randomization sequence generation program. The primary outcome was delivery within 24 hours from the first oxytocin infusion and the secondary outcome included time-to-delivery, mode of delivery, and additional maternal and neonatal outcomes. Seventy-two patients per group were randomized to reach 80% statistical power with a 20% difference in the primary outcome according to previous studies.

RESULTS

A total of 153 patients were randomized, 72 to the continuous oxytocin infusion group and 81 to the intermittent infusion group. The total oxytocin infusion time was similar between the groups. Patients in the continuous arm were more likely to deliver within 24 hours from oxytocin initiation (79.73% vs 62.96%, P<.05), and had a shorter oxytocin-to-delivery time interval, compared with patients receiving intermittent treatment (9.3±3.7 hours vs 21±11.7 hours, P<.001). Furthermore, time from ruptured membranes to delivery was shorter (9.3±3.7 hours vs 21±11.7 hours; P<.0001) and chorioamnionitis was less frequent (9.46% vs 21%; P<.05) in the continuous compared with the intermittent arm. Cesarean delivery rate was 20% in both groups (P=.226). There was no difference in postpartum hemorrhage, or adverse neonatal outcomes between the groups. Patients receiving continuous oxytocin infusion were more satisfied with the birthing experience.

CONCLUSION

Continuous infusion of oxytocin for labor induction in nulliparous patients with a favorable cervix may be superior to intermittent oxytocin infusion, because it shortens time-to-delivery, decreases chorioamnionitis rate, and improves maternal satisfaction, without affecting adverse maternal or neonatal outcomes.

Influence factor analysis and prediction model of successful application of high-volume Foley Catheter for labor induction

BACKGROUND

This study aimed to establish a clinical-based nomogram for predicting the success rate of high-volume Foley catheterization for labor induction.

METHODS

This retrospective study included 1149 full-term pregnant women who received high-volume Foley catheterization for labor induction from January 2019 to December 2021 in Changshu No.1 People's Hospital. Univariate and multivariate logistic regression analyses were performed, in which the labor induction success was set as dependent variables and the characteristics (including age, height, weight, BMI, gravidity, parity, gestational age, uterine height, abdominal circumference, cervical Bishop score, amniotic fluid index, cephalic presentation, neonatal weight, pregnancy complications, etc.) were set as independent variables. A nomogram scoring model was established based on these risk factors, and a calibration curve was plotted to verify the predictive accuracy of the model.

RESULTS

The success rate of labor induction was 83.55% (960/1149). Univariate analysis revealed that the risk factors associated with the success rate of high-volume Foley catheterization for labor induction were height, pregnancy, birth, age, weight, BMI, uterine height, abdominal circumference, and hypertension. Multivariate logistic regression analysis showed that age (OR = 0.950; 95% CI: 0.904 ~ 0.998), height (OR = 1.062; 95% CI: 1.026 ~ 1.100), BMI (OR = 0.871; 95% CI: 0.831 ~ 0.913), and parity (OR = 8.007; 95% CI: 4.483 ~ 14.303) were independent risk factors for labor induction success by high-volume Foley catheterization. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve in the prediction model was 0.752 (95% CI 0.716 ~ 0.788). A nomogram was constructed based on the final multivariate analysis with a corrected C-index of 0.748, which indicated that the model was calibrated reasonably.

CONCLUSION

Four risk factors were used to construct a nomogram to evaluate the success rate of high-volume Foley catheterization for labor induction. The nomogram provides a visual clinical tool to assist in the selection of the most appropriate mode of labor induction for pregnant women of different risk levels.

Randomized controlled trial comparing efficacy of a combination regime containing two cervical sensitizers (mifepristone + Foley's catheter) versus single agent mifepristone or Foley's catheter for labor induction in women attempting TOLAC at late third trimester with a dead fetus in utero

Randomized controlled trial comparing efficacy of a combination regime containing two cervical sensitizers (mifepristone + Foley's catheter) versus single agent mifepristone or Foley's catheter for labor induction in women attempting TOLAC at late third trimester with a dead fetus in utero.

AIM

To compare efficacy and safety of a new combination regime comprising of two cervical sensitizers used simultaneously with single agents, for labor induction in women attempting TOLAC at ≥34 weeks' gestation with a dead fetus.

METHOD

This was a multiarm randomized controlled trial (RCT) where participants received one of the three regimes-single agent oral Mifepristone 200 mg, intracervical Foley's catheter (16 Fr size, filled with 40 mL normal saline after intracervical instillation), and combination regime consisting of both used simultaneously. Number of women undergoing vaginal birth within 48 h of induction (VB48 ) was the primary outcome compared between groups.

RESULTS

VB48 was higher in participants on combination regime in comparison to participants on Foley's catheter (54 vs. 42). Total vaginal births were higher in participants on combination regime compared to both single agents (58 vs. 48 and 44). Duration and dose of oxytocin augmentation was lower in participants on combination regime compared to both single agents. Induction birth interval was short in participants on combination regime compared to those on Foley's catheter. Maternal complications between groups were similar.

CONCLUSION

Combination of cervical sensitizers for labor induction in late third trimester among women with dead fetus attempting TOLAC resulted in higher proportion of vaginal births and might reduce risk of scar dehiscence due to requirement of a lower dose of oxytocin for augmentation.

Six compared with 12 hours of Foley balloon placement for labor induction in nulliparous women with unripe cervices: a randomized controlled trial

BACKGROUND

Compared with a planned 12-hour placement of a double-balloon catheter, a planned 6-hour placement of a double-balloon catheter shortens the labor induction to delivery interval. The Foley catheter is low cost. Moreover, it has at least comparable effectiveness to the proprietary double-balloon labor induction devices. Of note, a 6-hour placement of a Foley balloon catheter in nulliparas has not been evaluated.

OBJECTIVE

This study aimed to evaluate 6- vs 12-hour Foley balloon placement for cervical ripening in the labor induction of nulliparas.

STUDY DESIGN

A randomized controlled trial was conducted at the Universiti Malaya Medical Centre from January 2022 to August 2022. Nulliparas aged ≥18 years, with a term, singleton pregnancy in cephalic presentation, with intact membranes, with reassuring fetal heart rate tracing, with an unripe cervix, and without any significant contractions, were recruited at admission for labor induction. Participants were randomized after successful Foley balloon insertion, for the balloon to be left passively in place for 6 or 12 hours and then removed to check for a ripened cervix. Amniotomy was performed once the cervix had ripened, followed by titrated oxytocin infusion to expedite labor and delivery. The primary outcome was the labor induction to delivery interval. The secondary outcomes were mostly from the core outcome set for trials on labor induction of labor trial reporting, such as change in the Bishop score after the intervention, use of an additional method for cervical ripening, time to delivery after double-balloon device removal, mode of delivery, indication for cesarean delivery, duration of oxytocin infusion, blood loss during delivery, presence of a third- or fourth-degree perineal tear, maternal infection, maternal satisfaction regional analgesia in labor, length of hospital stay, intensive care unit admission, cardiorespiratory arrest, need for hysterectomy. The neonatal outcomes were Apgar score at 1 and 5 minutes, neonatal intensive care unit admission, cord pH, neonatal sepsis, fetal birthweight, birth trauma, hypoxic-ischemic encephalopathy, or need for therapeutic hypothermia. Data were analyzed using the t test, Mann-Whitney U test, chi-square test, and Fisher exact test, as appropriate for the data type.

RESULTS

Overall, 240 women were randomized, 120 to each arm. The median labor induction to delivery intervals were 21.3 hours (interquartile range, 16.2-27.9) for the 6-hour balloon catheter placement and 26.0 hours (interquartile range, 21.5-30.9) for the 12-hour balloon catheter placement (P<.001). Of the secondary outcomes, for 6- vs 12-hour balloon catheter placement, the sequential use of additional cervical ripening agent (mostly Foley reinsertion) was 33 of 119 (27.5%) vs 17 of 120 (14.2%) (relative risk, 1.94; 95% confidence interval, 1.15-3.29; P=.011), Bishop score increase was 3 (interquartile range, 2.00-3.75) vs 3 (2.25-4.00) (P=.002), and the rate of recommendation to a friend was 83 of 118 (70.3%) vs 101 of 119 (84.9%) (relative risk, 0.83; 95% confidence interval; 0.72-0.95; P=.007), respectively. Cesarean delivery rates were 52 of 119 (43.7%) for the 6-hour balloon catheter placement and 64 of 120 (53.3%) for the 12-hour balloon catheter placement (relative risk, 0.82; 95% confidence interval, 0.63-0.07; P=.136), and maternal satisfaction scores (0-10 numerical rating scale) were 7 (interquartile range, 6-9) for the 6-hour balloon catheter placement and 7 (interquartile range, 7-9) for the 12-hour balloon catheter placement (P=.880).

CONCLUSION

Compared with a planned 12-hour Foley balloon catheter placement, a planned 6-hour Foley balloon placement shortens the time to birth, despite less cervical ripening at Foley balloon catheter removal and more additional cervical ripening agent use. However, the 6-hour balloon catheter placement was less likely to be recommended to a friend than the 12-hour balloon catheter placement.

Six vs 12 hours of Foley catheter balloon placement in the labor induction of multiparas with unfavorable cervixes: a randomized controlled trial

BACKGROUND

Planned 6- vs 12-hour placement of the double-balloon catheter for cervical ripening in labor induction hastens delivery. The Foley catheter is low-priced and typically performs at least as well as the proprietary double-balloon devices in labor induction. Maternal satisfaction with labor induction is usually inversely related to the speed of the process.

OBJECTIVE

This study aimed to compare Foley balloon placement for 6 vs 12 hours in the labor induction of multiparas with unfavorable cervixes.

STUDY DESIGN

A randomized controlled trial was conducted in a university hospital in Malaysia from January to October of 2022. Eligible multiparous women admitted for induction of labor for various indications were enrolled. Participant inclusion criteria were multiparity (at least 1 previous vaginal delivery of ≥24 weeks' gestation), age ≥18 years, term pregnancy >37 weeks' gestation, singleton pregnancy, cephalic presentation, intact membranes, normal fetal heart rate tracing, no significant contractions (< 2 in 10 minutes), and unfavorable cervix (Bishop score < 6). Participants were randomized after successful Foley balloon insertion for the balloon to be left in place for 6 or 12 hours of passive ripening before removal to check cervical suitability for amniotomy. The primary outcomes were the induction-to-delivery interval and maternal satisfaction with the allocated intervention assessed using a visual numerical rating scale (0-10). Secondary outcomes were derived in part from the core outcome set for trials on induction of labor (Core Outcomes in Women's and Newborn Health [CROWN]). Maternal outcomes were change in first Bishop score after intervention, use of additional method for cervical ripening, time to delivery after balloon removal, mode of delivery, indication for cesarean delivery, duration of oxytocin infusion, blood loss during delivery, presence of third- or fourth-degree perineal tear, maternal infection, use of regional analgesia in labor, length of hospital stay, intensive care unit (ICU) admission, cardiorespiratory arrest, and need for hysterectomy. The secondary neonatal outcomes were Apgar score at 1 and 5 minutes, neonatal intensive care unit (NICU) admission, cord blood pH, neonatal sepsis, birthweight, birth trauma, hypoxic-ischemic encephalopathy, or need for therapeutic hypothermia. Analyses were conducted with the t-test, Mann-Whitney U test, chi-square test, and Fisher exact test, as appropriate.

RESULTS

A total of 220 women were randomized (110 to each intervention). Regarding the 2 primary outcomes, the induction-to-delivery intervals were a median (interquartile range) of 15.9 (12.0-24.0) and 21.6 (17.3-26.0) hours (P<.001), and maternal satisfaction scores were 7 (6-8) and 7 (6-8) (P=.734) for 6- and 12-hour placement, respectively. The following rates were observed for 6- and 12-hour placement, respectively: sequential use of additional cervical ripening agent (Foley reinsertion)-29 per 110 (26.4%) and 13 per 110 (11.8%) (relative risk, 2.23; 95% confidence interval, 1.23-4.10; P=.006); spontaneous balloon expulsion-22 per 110 (20.0%) and 37 per 110 (33.6%) (relative risk, 0.60; 95% confidence interval, 0.38-0.94; P=.022); and recommendation of the allocated intervention to a friend-61 per 110 (73.6%) and 87 per 110 (79.1%) (relative risk, 0.90; 95% confidence interval, 0.80-1.08; P=.341). Other secondary outcomes, including cesarean delivery, were not significantly different.

CONCLUSION

Foley balloon placement for 6 hours for cervical ripening in parous women hastens birth but does not increase maternal satisfaction relative to 12-hour placement. Foley reinsertion for additional ripening was more frequent in the 6-hour group.

Induction of labor via Foley balloon catheter placement for 6 vs 12 hours in women with 1 previous cesarean delivery and unfavorable cervices: a randomized controlled trial

BACKGROUND

Induction of labor in women with 1 previous cesarean delivery and unripe cervices is a high-risk process, carrying an increased risk of uterine rupture and the need for cesarean delivery. Balloon ripening is often chosen as prostaglandin use is associated with an appreciable risk of uterine rupture in vaginal birth after cesarean delivery. A shorter duration of placement of the balloon typically expedites delivery; however, this has not been evaluated in induction of labor after 1 previous cesarean delivery.

OBJECTIVE

This study aimed to compare Foley balloon catheter placement for 6 vs 12 hours in induction of labor after 1 previous cesarean delivery.

STUDY DESIGN

A randomized controlled trial was conducted in a university hospital in Malaysia from January 2022 to February 2023. Eligible women with 1 previous cesarean delivery admitted for induction of labor were enrolled. Participants were randomized after balloon catheter insertion for 6 or 12 hours of passive ripening before balloon deflation and removal to check cervical status for amniotomy. The primary outcome was the induction of labor to delivery interval. The secondary outcomes were largely derived from the core outcome set for trials on induction of labor (Core Outcomes in Women's and Newborn Health [CROWN]). The Student t test, Mann-Whitney U test, chi-square test, and Fisher exact test were used as appropriate for the data.

RESULTS

Overall, 126 women were randomized, 63 to each intervention. The mean induction of labor to delivery intervals were 23.0 (standard deviation, ±8.9) in the 6-hour arm and 26.6 (standard deviation, ±7.1) in the 12-hour arm (mean difference, -3.5 hours; 95% confidence interval, -6.4 to -0.7; P=.02). The median induction of labor (Foley balloon catheter insertion) to Foley balloon catheter removal intervals were 6.0 hours (interquartile range, 6.0-6.3) in the 6-hour arm and 12.0 hours (interquartile range, 12.0-12.5) in the 12-hour arm (P<.001). The median induction of labor to amniotomy intervals were 14.1 hours (interquartile range, 9.3-21.8) in the 6-hour arm and 19.0 hours (interquartile range, 15.9-22.0) in the 12-hour arm (P=.02). The usage rates of epidural analgesia in labor were 46.0% (29/63) in the 6-hour arm and 65.1% (41/63) in the 12-hour arm (relative risk, 0.71; 95% confidence interval, 0.51-0.98; P=.03). Spontaneous balloon catheter expulsion rates were 22.2% (14/63) in the 6-hour arm and 17.5% (11/63) in the 12-hour arm (relative risk, 1.27; 95% confidence interval, 0.63-2.58; P=.50), and additional ripening use rates (Foley reinsertion) were 46.0% (29/63) in the 6-hour arm and 31.7% (20/63) in the 12-hour arm (relative risk, 1.45; 95% confidence interval, 0.92-2.27; P=.10). The results were not different. Moreover, maternal satisfaction scores (0-10 numerical rating scale) of 9 (range, 8-10) in the 6-hour arm and 9 (range, 8-10) in the 12-hour arm (P=.41) were not different. Other secondary maternal and neonatal outcomes were not significantly different either.

CONCLUSION

Foley balloon catheter placement for 6 hours hastened birth and reduced epidural analgesia use in labor without a change in maternal satisfaction.

Double-vs single-balloon catheter for induction of labor: Systematic review and individual participant data meta-analysis

INTRODUCTION

Evidence comparing double-balloon vs single-balloon catheter for induction of labor is divided. We aim to compare the efficacy and safety of double-vs single-balloon catheters using individual participant data.

MATERIAL AND METHODS

A search of Ovid MEDLINE, Embase, Ovid Emcare, CINAHL Plus, Scopus, and clinicaltrials.gov was conducted for randomized controlled trials published from March 2019 until April 13, 2021. Earlier trials were identified from the Cochrane Review on Mechanical Methods for Induction of Labour. Randomized controlled trials that compared double-balloon with single-balloon catheters for induction of labor in singleton gestations were eligible. Participant-level data were sought from trial investigators and an individual participant data meta-analysis was performed. The primary outcomes were rates of vaginal birth achieved, a composite measure of adverse maternal outcomes and a composite measure of adverse perinatal outcomes. We used a two-stage random-effects model. Data were analyzed from the intention-to-treat perspective.

RESULTS

Of the eight eligible randomized controlled trials, three shared individual-level data with a total of 689 participants, 344 women in the double-balloon catheter group and 345 women in the single-balloon catheter group. The difference in the rate of vaginal birth between double-balloon catheter and single-balloon catheter was not statistically significant (relative risk [RR] 0.93, 95% confidence interval [CI] 0.86-1.00, p = 0.050; I2 0%; moderate-certainty evidence). Both perinatal outcomes (RR 0.81, 95% CI 0.54-1.21, p = 0.691; I2 0%; moderate-certainty evidence) and maternal composite outcomes (RR 0.65, 95% CI 0.15-2.87, p = 0.571; I2 55.46%; low-certainty evidence) were not significantly different between the two groups.

CONCLUSIONS

Single-balloon catheter is at least comparable to double-balloon catheter in terms of vaginal birth rate and maternal and perinatal safety outcomes.

An evaluation of cervical maturity for Chinese women with labor induction by machine learning and ultrasound images

BACKGROUND

To evaluate the improvement of evaluation accuracy of cervical maturity for Chinese women with labor induction by adding objective ultrasound data and machine learning models to the existing traditional Bishop method.

METHODS

The machine learning model was trained and tested using 101 sets of data from pregnant women who were examined and had their delivery in Peking University Third Hospital in between December 2019 and January 2021. The inputs of the model included cervical length, Bishop score, angle, age, induced labor time, measurement time (MT), measurement time to induced labor time (MTILT), method of induced labor, and primiparity/multiparity. The output of the model is the predicted time from induced labor to labor. Our experiments analyzed the effectiveness of three machine learning models: XGBoost, CatBoost and RF(Random forest). we consider the root-mean-squared error (RMSE) and the mean absolute error (MAE) as the criterion to evaluate the accuracy of the model. Difference was compared using t-test on RMSE between the machine learning model and the traditional Bishop score.

RESULTS

The mean absolute error of the prediction result of Bishop scoring method was 19.45 h, and the RMSE was 24.56 h. The prediction error of machine learning model was lower than the Bishop score method. Among the three machine learning models, the MAE of the model with the best prediction effect was 13.49 h and the RMSE was 16.98 h. After selection of feature the prediction accuracy of the XGBoost and RF was slightly improved. After feature selection and artificially removing the Bishop score, the prediction accuracy of the three models decreased slightly. The best model was XGBoost (p = 0.0017). The p-value of the other two models was < 0.01.

CONCLUSION

In the evaluation of cervical maturity, the results of machine learning method are more objective and significantly accurate compared with the traditional Bishop scoring method. The machine learning method is a better predictor of cervical maturity than the traditional Bishop method.

Comparison of the efficacy between controlled-release dinoprostone delivery system (PROPESS) and Cook's double balloon catheter plus oxytocin: A retrospective single-center study in Japan

AIMS

To compare the efficacy of the controlled-release dinoprostone delivery system (PROPESS) and Cook's double balloon catheter (DBC) plus oxytocin as induction treatment.

METHODS

A total of 197 term pregnant women with unfavorable cervix were admitted for scheduled induction and enrolled retrospectively (PROPESS, 113; Cook's DBC plus oxytocin, 84). The main birth outcomes were cervical ripening at the treatment-end and 24 h after the treatment-start, and rate of vaginal birth. Logistic regression and propensity score matching analyses were performed to evaluate the association between the outcomes and clinical characteristics including which treatment was selected.

RESULTS

The choice of PROPESS was associated with the success of cervical ripening at 24 h after (adjusted odds ratio (OR) 2.17, 95% confidence interval (CI) 1.11-4.26, p = 0.024) and increased the rate of vaginal birth (adjusted OR 2.03, 95% CI 1.04-3.98, p = 0.039). Similar trends in the association between PROPESS and birth outcomes were maintained after adjusting for propensity scores (p = 0.072 and p = 0.163, respectively). However, some of the women with gestational age of early 39 weeks and low Bishop scores could achieve cervical ripening at 24 h after using Cook's DBC plus oxytocin, and none by PROPESS.

CONCLUSION

Our findings suggest the possibility of slight advantages of PROPESS for scheduled induction of labor. In women with early term and extremely low Bishop scores, Cook's DBC plus oxytocin may be a superior or alternative treatment to PROPESS. Therefore, the optimal choice of induction treatment should be managed on an individual basis.

Expediting labor induction in severe pre-eclampsia by earlier initiation of oxytocin after cervical ripening: A randomized study from India

OBJECTIVE

To observe whether induction of labor (IoL) among women with severe pre-eclampsia (PE) can be expedited by initiating oxytocin early (after 6 h) than after 12 h following cervical ripening with a combined method.

METHODS

Women with severe PE and Bishop's < 6 (n = 96) were randomized into two groups. All women received cervical ripening with a combined method (intracervical Foley's plus dinoprostone gel 0.5 mg) following which Group 1 women received oxytocin after 6 h (with Foley's in-situ) and Group 2 after 12 h (after removing Foley's) RESULTS: Majority were nulliparous (63% in group 1 and 77% in group 2) and the mean gestation was similar (35.3 ± 2.98 weeks in group 1 and 35.5 ± 3.09 in group 2). Nearly half the women had partial HELLP/ HELLP (47.9% and 54.1%; in groups 1 and 2, respectively). The induction-delivery interval (IDI) was significantly reduced in group 1 (16 h 6 min vs 22 h 6 min in group 2; p = 0.001). The cesarean section (CS) rate was 37.5% in group 1 and 31.3% in group 2 (p = 0.525), but the study was underpowered to assess this outcome. The neonatal outcome was similar, 92/96 neonates were discharged after a hospital stay of 3-52 days. There were 4 neonatal deaths (1 in group 1 and 3 in group 2) of extreme or very preterm neonates (27-30 + 6 wks) with birth weight of 735-965 gm.

CONCLUSION

Among women with severe PE undergoing IoL, initiating oxytocin 6 h after cervical ripening with a combined method reduced the IDI significantly as compared to initiating it after 12 h, with a similar CS rate and neonatal outcome.

Outpatient versus inpatient cervical ripening with a slow-release dinoprostone vaginal insert in term pregnancies on maternal, neonatal, and birth outcomes: A systematic review

BACKGROUNDS

Outpatient induction of labor (IOL) is an alternative choice offered to pregnant women requiring cervical ripening. Outpatient IOL can provide solutions in terms of women empowerment, but most importantly promotes as normal labor as possible, within the medical context of the IOL. The objectives of this systematic review were to assess safety and effectiveness of cervical ripening performed with a slow-release dinoprostone vaginal insert in term pregnancies in two settings: the outpatient (home) versus the inpatient (hospital).

METHODS

The electronic databases Cinahl, Embase, Medline and Maternity and Infant Care were searched to detect studies that met the inclusion criteria. Both reviewers collected the data and assessed the quality of the studies and assessed the pooled odds ratio using a 95% confidence interval and a random-effects model. Primary outcomes were linked to maternal and neonatal morbidity. Secondary outcomes were related to birth outcomes.

RESULTS

No statistical difference was seen between the outpatient and inpatient setting in terms of maternal complications, neonatal morbidity, cesarean section, and labor onset <24 h. Women in the outpatient setting were significantly less likely to experience uterine hyperstimulation, and they were also significantly more likely to require oxytocin to augment or induce their labor than the women in the inpatient setting. Women in the outpatient setting were more satisfied with the cervical ripening experience.

CONCLUSIONS

Cervical ripening with a slow-release dinoprostone vaginal insert in term pregnancies in the outpatient setting appears as safe as the inpatient setting in terms of maternal, neonatal, and birth outcomes.

Comparison of labor duration of induced labor with dinoprostone insert vs spontaneous labor

OBJECTIVES

Labor induction is one of the most common procedures in modern obstetrics. One in five pregnant women and 30-40% of women delivering vaginally undergo this procedure. If the cervical status is unfavorable, a ripening process is used prior to induction to shorten the duration of oxytocin administration and maximize the possibility of vaginal birth. The aim of this study was to compare the duration of labor induced with dinoprostone vaginal insert to spontaneous labor.

MATERIAL AND METHODS

It was a retrospective study conducted between May 2019 and February 2021 in the tertiary reference center, the Obstetrics and Perinatology Department of the Jagiellonian University Hospital in Krakow. The research group involved 182 patients in singleton pregnancy at term, qualified for cervical ripening procedure. The control group consisted of 178 patients that were delivering spontaneously and admitted to the delivery ward in the first stage of labor. Statistical analysis was performed to compare the duration of labor between groups. To find factors affecting the procedure we compared different models consisting of maternal and fetal characteristics.

RESULTS

Successful vaginal delivery in the dinoprostone group was achieved in the group of 88% of patients. There was no significant difference in labor duration between the groups: 315 minutes in the study group and 300 min in the control group. Only being primipara was a factor related to longer labor in both groups.

CONCLUSIONS

Pre-induction with dinoprostone insert and additional foley catheter, if indicated, does not make labor longer in comparison with spontaneous labor.

A comparison of 30-, 50-, and 60-mL foley catheter balloon volume and time to achieve cervical ripening for labor induction: A triple-blind randomized controlled trial

Background

Cervical ripening is one of the most important determinants of the outcome of induction of labor. The findings of studies on the most efficacious inflatable catheter balloon volume for pre-induction cervical ripening have been inconclusive.

Aim

To compare the efficacy of the use of different intracervical Foley catheter balloon volumes (30-, 50-, and 60-mL) on cervical ripening.

Subjects and Methods

This study was a triple-blind randomized controlled trial. Two hundred and sixteen women with a Bishop score ≤5 at term were randomly assigned into three groups (1:1:1) to receive an intracervical single size eighteen Foley balloon catheter inflated either with 30-mL (control arm) or 50-mL and 60-mL (intervention arm) of sterile saline which was retained for a duration of 12 h. The primary outcome measures were the mean change in Bishop score and achieving a Bishop score of ≥6 at the twelfth-hour post-Foley catheter balloon insertion.

Results

In the total study population and among nulliparous women, the 50-mL and 60-mL balloons compared with the 30-mL Foley catheter balloon achieved a statistically significantly greater mean change in Bishop scores at the twelfth hour\post-insertion (P = 0.005 and P = 0.001), while the 60-mL balloon compared with the 30-mL and 50-mL balloons achieved statistically significant higher mean change in Bishop scores among multiparous women (P = 0.047 and P = 0.003) and cervical dilatation irrespective of parity (P = 0.003 and P = 0.002), at the twelfth-hour post-insertion. The larger catheter balloons were also associated with a statistically significant greater chance of having an induction to delivery interval of <12 h in nulliparous women P = 0.003.

Conclusion

The findings of this study showed that the larger single Foley catheter balloon volumes (50-mL and 60-mL) aside from being well tolerated and acceptable have the ability to induce faster changes in Bishop score, produce higher cervical dilation, and thus likely reduce significantly the total labor induction process compared to the 30-mL single catheter balloon volume irrespective of parity.

Application of intrauterine balloons in cervical ripening

INTRODUCTION

At present, the double balloon represented by the COOK Cervix Ripening Balloon and the single balloon represented by the Foley catheter are the commonly used intrauterine balloons. The application of intrauterine balloons in cervical ripening has evolved over 100 years. Although intrauterine balloons have been widely used in cervical ripening, the effect of labor induction in clinical practice does not satisfy all clinicians, especially patients with poor cervical maturity.

AREAS COVERED

The research in this review is about intrauterine balloons and cervical ripening.

EXPERT OPINION

This article reviews the historical evolution and different application methods of intrauterine balloons in cervical ripening, such as application range, placement method and placement duration of intrauterine balloons, volume and temperature of the solution fillings, and whether to apply traction to the catheter. We aim to better understand the principle of intrauterine balloons in cervical ripening and make this method more effective.

Oxytocin versus prostaglandins for labour Induction of women with an unfavourable cervix after 24 hours of cervical ripening (OPIC): protocol for an open multicentre randomised non-inferiority trial

INTRODUCTION

It remains uncertain whether the most appropriate management for women with an unfavourable cervix after 24 hours of cervical ripening is repeating the ripening procedure or proceeding directly to induction by oxytocin. No adequately powered trial has compared these strategies. We hypothesise that induction of labour with oxytocin among women who have just undergone an ineffective first ripening procedure is not associated with a higher risk of caesarean delivery than a repeated cervical ripening with prostaglandins.

METHODS AND ANALYSIS

We will conduct a multicentre, non-inferiority, open-label, randomised controlled trial aimed at comparing labour induction by oxytocin with a second cervical ripening that uses prostaglandins (slow-release vaginal dinoprostone; oral misoprostol 25 µg; dinoprostone vaginal gel 2 mg). Women (n=1494) randomised in a 1:1 ratio in 10 French maternity units must be ≥18 years with a singleton fetus in vertex presentation, at a term from ≥37+0 weeks of gestation, and have just completed a 24-hour cervical ripening procedure by any method (pharmacological or mechanical) with a Bishop score ≤6. Exclusion criteria comprise being in labour, having more than 3 contractions per 10 min, or a prior caesarean delivery or a history of uterine surgery, or a fetus with antenatally suspected severe congenital abnormalities or a non-reassuring fetal heart rate. The primary endpoint will be the caesarean delivery rate, regardless of indication. Secondary outcomes concern delivery, perinatal morbidity, maternal satisfaction and health economic evaluations. The nature of the assessed procedures prevents masking the study investigators and patients to group assignment.

ETHICS AND DISSEMINATION

All participants will provide written informed consent. The ethics committee 'Comité de Protection des Personnes Ile de France VII' approved this study on 2 April 2021 (No 2021-000989-15). Study findings will be submitted for publication and presented at relevant conferences.

TRIAL REGISTRATION NUMBER

NCT04949633.

432b: Cervical Ripening

OBJECTIVE

This guideline presents evidence and recommendations for cervical ripening and induction of labour. It aims to provide information to birth attendants and pregnant individuals on optimal perinatal care while avoiding unnecessary obstetrical intervention.

TARGET POPULATION

All pregnant patients.

BENEFITS, HARMS, AND COSTS

Consistent interprofessional use of the guideline, appropriate equipment, and trained professional staff enhance safe intrapartum care. Pregnant individuals and their support person(s) should be informed of the benefits and risks of induction of labour.

EVIDENCE

Literature published to March 2022 was reviewed. PubMed, CINAHL, and the Cochrane Library were used to search for systematic reviews, randomized controlled trials, and observational studies on cervical ripening and induction of labour. Grey (unpublished) literature was identified by searching the websites of health technology assessment and health technology related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

All providers of obstetrical care.

RECOMMANDATIONS

432a: Cervical Ripening and Induction of Labour - General Information

OBJECTIVE

This guideline presents evidence and recommendations for cervical ripening and induction of labour. It aims to provide information to birth attendants and pregnant individuals on optimal perinatal care while avoiding unnecessary obstetrical intervention.

TARGET POPULATION

All pregnant patients.

BENEFITS, HARMS, AND COSTS

Consistent interprofessional use of the guideline, appropriate equipment, and trained professional staff enhance safe intrapartum care. Pregnant individuals and their support person(s) should be informed of the benefits and risks of induction of labour.

EVIDENCE

Literature published to March 2022 was reviewed. PubMed, CINAHL, and the Cochrane Library were used to search for systematic reviews, randomized controlled trials, and observational studies on cervical ripening and induction of labour. Grey (unpublished) literature was identified by searching the websites of health technology assessment and health technology related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations).

INTENDED AUDIENCE

All providers of obstetrical care.

RECOMMANDATIONS

Cervical ripening with laminaria tents prior to second trimester induction of labor

BACKGROUND

Induction abortion in the second trimester may be favored in some instances, such as in women with compounding medical conditions or when skilled providers are not available. Various methods of pre-induction cervical preparation have been used to shorten the length of induction and decrease the risk of complications. The benefits of cervical preparation with laminaria before D&E have been well studied, but the benefits of laminaria before medical induction are less clear.

OBJECTIVE

To determine if overnight cervical preparation with laminaria tents shortens delivery interval in women undergoing 2nd trimester induction of labor (IOL) with misoprostol.

STUDY DESIGN

This was a retrospective cohort study comparing overnight intracervical laminaria placement followed by misoprostol to misoprostol alone for 2nd trimester IOL between 1/2000 and 12/2010. Women were excluded if the reason for IOL was preterm labor or preterm premature rupture of membranes or if misoprostol was not used as the primary induction agent. The primary outcome was time from misoprostol administration to delivery.

RESULTS

126 women were analyzed including 36 (29%) who received laminaria + misoprostol and 90 (71%) who received misoprostol alone. Women in the laminaria + misoprostol group were significantly older (30 yrs [14-44] vs. 27 yrs [17-43], p = .029). Induction for fetal anomaly (92% vs. 34%, p ≤ .001) and the use of feticide (56% vs. 13%, p ≤ .001) were more common in the laminaria + misoprostol group. The mean time to delivery in the laminaria + misoprostol group was 6 h longer compared to the misoprostol only group; 19 ± 8 h compared to 13 ± 12hrs (p = .007). There was no difference in fetal to placental delivery time (p = .329), total misoprostol dose (p = .182), or length of hospitalization (p = .144) however, significantly more women completed abortion at 24 hrs in the misoprostol alone group (90% vs. 61%, p ≤ .001).

CONCLUSIONS

The use of laminaria tents for overnight cervical preparation does not expedite delivery times in patients undergoing 2nd trimester IOL with misoprostol.

Progesterone and its receptor signaling in cervical remodeling: Mechanisms of physiological actions and therapeutic implications

The remodeling of the cervix from a closed rigid structure to one that can open sufficiently for passage of a term infant is achieved by a complex series of molecular events that in large part are regulated by the steroid hormones progesterone and estrogen. Among hormonal influences, progesterone exerts a dominant role for most of pregnancy to initiate a loss of tissue strength yet maintain competence in a phase termed softening. Equally important are the molecular events that abrogate progesterone function in late pregnancy to allow a loss of tissue competence and strength during cervical ripening and dilation. In this review, we focus on current understanding by which progesterone receptor signaling for the majority of pregnancy followed by a loss/shift in progesterone receptor action at the end of pregnancy, collectively ensure cervical remodeling as necessary for successful parturition.

Comparison of delivery outcomes in low-dose and high-dose oxytocin regimens for induction of labor following cervical ripening with a balloon catheter: A retrospective observational cohort study

A variety of oxytocin regimens are used for labor induction and augmentation. Considering the increasing rates of labor induction, it is important to assess the most optimal oxytocin regimen without compromising maternal and fetal safety. The aim of this study was to compare delivery outcomes of low-dose and high-dose oxytocin induction protocols. This retrospective cohort study of 487 women comparing low-dose oxytocin protocol (n = 280) and high-dose oxytocin protocol (n = 207) in labor induction following cervical ripening by balloon catheter was performed in Helsinki University Hospital after implementation of a new oxytocin induction protocol. The study included two six-month cohorts from 2016 and 2019. Women with vital singleton pregnancies ≥37 gestational weeks, cephalic presentation, and intact amniotic membranes were included. The primary outcome was the rate of vaginal delivery. The secondary outcomes were the rates of maternal and neonatal infections, postpartum hemorrhage, umbilical artery blood pH-value, admission to neonatal intensive care, and induction-to-delivery interval. Statistical analyses were performed by using IBM SPSS Statistics for Windows (Armonk, NY, USA). The rate of vaginal delivery was higher [69.9% (n = 144) vs. 47.9% (n = 134); p<0.004] and the rates of maternal and neonatal infection were lower during the new high-dose oxytocin protocol [maternal infections 13.6% (n = 28) vs. 22.1% (n = 62); p = 0.02 and neonatal infection 2.9% (n = 6) vs. 14.6% (n = 41); p<0.001, respectively]. The rates of post-partum hemorrhage, umbilical artery blood pH-value <7.05 or neonatal intensive care admissions did not differ between the cohorts. The median induction-to-delivery interval was shorter in the new protocol [32.0 h (IQR 18.5–42.7) vs. 37.9 h (IQR 27.8–52.8); p<0.001]. In conclusion, implementation of the new continuous high-dose oxytocin protocol resulted in higher rate of vaginal delivery and lower rate of maternal and neonatal infections. Our experience supports the use of high-dose continuous oxytocin induction regimen with a practice of stopping oxytocin once active labor is achieved, and a 15–18-hour maximum duration for oxytocin induction in the latent phase of labor following cervical ripening with a balloon catheter.

Change in timing of induction protocol in nulliparous women to optimise timing of birth: results from a single centre study

BACKGROUND

Induction of labour (IOL) is a common obstetric intervention. When planning IOL, especially in women at risk for complications at delivery, the aim should be for delivery to occur when senior staff are available to optimise safe care.

METHODS

A change in timing of IOL protocol at our institution was introduced in November 2018 aiming to increase births occurring "in-hours" defined as 08:00 to 20:00 h. This retrospective cohort study compares the odds of "in-hours" birth before and after the intervention and the association on birth outcomes. The study compared outcomes during the new IOL pathway period to a historical birth cohort from January to December 2017. Inclusion criteria were nulliparous women undergoing planned IOL at term with a cephalic singleton pregnancy. Logistic regression was used to compare odds of in-hours birth for the 2 periods with adjustment for maternal age at delivery, gestation, more than 2 cervical ripening agents required, undergoing IOL for post-dates pregnancy, mode of birth, whether or not IOL proceeded according to planned protocol and missing values using multiple imputation.

RESULTS

The rate of deliveries occurring in-hours were higher following the intervention; n = 118/285 (45.6%) pre-intervention versus n = 251/470 (53.4%) post-intervention; adjusted OR = 1.47, 95% CI = 1.07-2.01, p = 0.02). The percentage of caesarean sections (CS) occurring in-hours was significantly lower in the pre-intervention group n = 71/153 (28.3%) compared with the post intervention group = 35/132(46.4%) (p < 0.001)). The rate of CS was higher in the pre intervention n = 132/285(46.3%) compared with the post intervention group n = 153/470 (32.4%)).

CONCLUSIONS

The change in induction procedures was associated with a significantly higher rate of births occurring in-hours and a lower rate of overall of CS. This policy change led to a better pattern of timing of birth for nulliparous women undergoing IOL.