Mechanical Methods of Cervical Ripening and Labor Induction

Efficacy and safety of oral and vaginal administration of misoprostol for induction of labor in high-risk obese pregnant women with hypertension or diabetes mellitus

OBJECTIVE

This study aims to compare the safety and efficacy of misoprostol administered orally and vaginally in obese pregnant women at term with either gestational hypertension or diabetes.

METHODS

A total of 264 pregnant women were enrolled and categorized into two groups based on their primary condition: hypertension (134 cases) or diabetes mellitus (130 cases) and were further divided into subgroups for misoprostol administration: orally (Oral group) or vaginally (Vaginal group). The primary outcomes measured were changes in the Bishop score following treatment, induction of labor (IOL) success rates, requirement for oxytocin augmentation, duration of labor, mode of delivery, and cesarean section rates.

RESULTS

Significant enhancements in Bishop scores, decreased cesarean section rates and increased success rates of IOL were noted in both administration groups. The incidence of vaginal delivery within 24 h was significantly higher in the Vaginal group compared to the Oral group. Adverse effects, including nausea, uterine overcontraction, hyperfrequency of uterine contraction and uterine hyperstimulation without fetal heart rate deceleration, were significantly more prevalent in the Vaginal group than in the Oral group.

CONCLUSION

Misoprostol administration, both orally and vaginally, proves effective for labor induction in obese pregnant women with hypertension or diabetes. However, the oral route presents a lower risk of adverse maternal and neonatal outcomes, suggesting its preference for safer labor induction in this demographic.

Digital versus speculum insertion of Foley catheter for labor induction: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To compare Foley catheter insertion by digital blind method to its placement with a sterile speculum in women with unripe cervix for induction of labor.

METHODS

A systematic search was conducted in Cochrane Library, PubMed, Web of Science, and Scopus databases for randomized clinical trials (RCTs) from inception to July 2023. Included studies compared digital to speculum placement of the Foley catheter for labor induction. Data from the included studies were extracted and pooled using RevMan software for meta-analysis. The primary outcome was pain score during the procedure measured by the Visual Analog Scale (VAS). Secondary outcomes included Foley catheter insertion duration, cesarean delivery rate, induction to delivery interval, Bishop score, need for other cervical ripening methods, maternal satisfaction, and maternal fever.

RESULTS

Four RCTs involving a total of 600 patients met the inclusion criteria. Pain during the procedure and Foley catheter insertion duration were significantly reduced in the digital insertion group compared to the speculum-guided group (p < 0.05). The Bishop score showed a significant improvement in the digital Foley catheter placement group. However, there were no statistically significant differences in the cesarean delivery rate or the requirement for additional cervical ripening methods between the two groups. Maternal satisfaction with the delivery process was significantly improved in the digital insertion group (p < 0.001). Induction to delivery interval and maternal fever were comparable between both groups.

CONCLUSIONS

Digital placement of Foley catheter can be considered as an alternative to the sterile speculum method for pre-induction cervical ripening. More trials are required to confirm our findings.

Clinical Factors Associated with Intrapartum Presentation Change after Mechanical Cervical Ripening

OBJECTIVE

The use of mechanical cervical ripening with balloon devices is common during induction of labor; however, there is risk for displacement of the fetal presenting part during its insertion. This study sought to investigate the clinical risk factors associated with an intrapartum presentation change from cephalic to noncephalic presentation after mechanical cervical ripening.

STUDY DESIGN

Data were obtained from the Consortium on Safe Labor, a multicenter retrospective study that abstracted detailed labor and delivery information from electronic medical records in 19 hospitals across the United States. All women with fetal cephalic confirmed position on admission undergoing induction of labor with mechanical cervical ripening were included. Women who had a cesarean delivery for noncephalic presentation were compared with women who had a vaginal delivery or cesarean delivery for other indications. Models were adjusted for nulliparity, multiple gestation, and gestational age.

RESULTS

A total of 3,462 women met inclusion criteria, with 1.3% (n = 46) having an intrapartum presentation change from cephalic to noncephalic presentation after mechanical cervical ripening. Those who had a cesarean delivery for an intrapartum presentation change were more likely to be nulliparous (82.6 vs. 65.4%, p = 0.01), less than 34 weeks' gestation (6.5 vs. 1.3%, p = 0.02), and have twins (6.5 vs. 1.2%, p = 0.02). In adjusted analysis, twins were associated with an increased odds of cesarean delivery for intrapartum presentation change (adjusted odds ratio [aOR]: 4.43; 95% confidence interval [CI]: 1.25-15.77), whereas multiparity reduced the odds (aOR: 0.38; 95% CI: 0.17-0.82).

CONCLUSION

Nulliparity and multifetal gestation are associated with a cesarean delivery for an intrapartum presentation change after mechanical cervical ripening.

KEY POINTS

· Intrapartum presentation change after mechanical cervical ripening is low at 1.3%.. · Nulliparity and multifetal gestation are associated with a cesarean delivery for presentation change.. · There were no significant differences in neonatal morbidity by delivery status to delivery type..

Comparison of digital and speculum-guided methods of transcervical Foley catheter insertion in primigravida undergoing cervical ripening at term gestation: a noninferiority randomized clinical trial

BACKGROUND

Foley catheter insertion is frequently used for cervical ripening during the induction of labor. However, the insertion failure, safety, maternal side effects, complications, and satisfaction of digital compared with speculum-guided Foley catheter placement have not been evaluated in a large trial involving primigravida.

OBJECTIVE

The study aimed to compare the insertion failure rate of digital and speculum-based transcervical Foley catheter placement in primigravida. The co-primary outcome was insertion-associated pain. The secondary outcomes were the time required for successful insertion, maternal satisfaction, and maternal complications within 24 hours of Foley insertion.

STUDY DESIGN

This randomized, open-label, parallel-arm, noninferiority clinical trial was performed in a large tertiary care university hospital. Primigravida aged >18 years with term gestation (≥37 weeks) were included in this study. Additional inclusion criteria for enrollment in this study were singleton pregnancy with a cephalic presentation, intact membrane, a Bishop score of ≤5, and reassuring preinduction fetal heart rate tracing. All women planned for cervical ripening were assessed for eligibility and were randomized into digital or speculum arms. Foley catheter insertion was performed in a supine lithotomy position. Vaginal and cervical cleaning were performed before insertion. A 22-French Foley balloon catheter was guided digitally or via speculum to position the bulb at the level of the internal os using water-soluble lubricant. Insertion-associated pain was measured using a visual numeric rating scale, and maternal satisfaction was assessed using a set of questions.

RESULTS

Four hundred and sixty-nine pregnant women were assessed for eligibility, and 446 patients were enrolled and randomized. The median age of the parturients was 24 (19-40) and 24 (18-38) years, respectively. The body mass index, gestational age at randomization, the incidence of postdated pregnancy, and prerandomization Bishop scores were comparable. Insertion failure was observed in 24 (10.8%) and 17 (7.6%) women in digital and speculum arms, respectively (relative risk=1.41 [95% confidence interval, 0.78-2.55]; P=.25). Requirements of >1 attempt (5.4% vs 3.6%) followed by the change in hands (3.6% vs 2.7%) were the most common reasons for insertion failure. The median (interquartile range) visual numeric rating scale was comparable (6 [2-9] vs 5 [2-10]; P=.15). The time taken for successful insertion was similar (58 [12-241] vs 54 [10-281]; P=.30). 9.4% and 10.8% of women required additional methods of cervical ripening. More women in the speculum group (41.7% vs 33.2%; P=.06) felt a medium level of discomfort than the digital group.

CONCLUSION

Insertion failure and insertion-related pain in the digital approach were comparable to the speculum-guided approach for transcervical Foley catheter insertion in primigravida for cervical ripening. Nevertheless, maternal satisfaction was higher in the digital group because of a lesser level of discomfort.

A Comparative Study of the Efficacy and Safety of Oral Misoprostol, Intravenous Oxytocin, and Intravaginal Dinoprostone for Labor Induction in Pakistani Women

INTRODUCTION

A frequent medical procedure to accelerate labor is the induction of labor. There are different methods of labor induction, including the use of medications such as misoprostol, oxytocin, and dinoprostone.

OBJECTIVE

This research compared the effectiveness and safety of oral misoprostol, intravenous oxytocin, and intravaginal dinoprostone for labor induction in Pakistani women.

METHODOLOGY

A study was conducted in the Department of Obstetrics and Gynaecology, Hayatabad Medical Complex-Medical Teaching Institute (MTI) and Lady Reading Hospital-MTI, Peshawar, Pakistan, over two years. It included 378 women between 38 and 42 gestational weeks, divided into three groups of 126 women each. The oral misoprostol group was given a maximum of six doses of a 25 μg oral misoprostol solution (oral misoprostol tablet of 200 μg dissolved in 200 ml) at intervals of two hours. The drip rate for the intravenous oxytocin group ranged from 6 mIU/minute to 37 mIU/minute. The intravaginal dinoprostone group received a controlled-release vaginal insert containing 10mg of intravaginal dinoprostone, which was left in place for 12 hours.

RESULTS

More women in the oral misoprostol group (n=94; 74.6%) had successful inductions when compared to the intravaginal dinoprostone (n=83; 65.9%) and intravenous oxytocin (n = 77; 64.71%) groups. Oral misoprostol had the greatest proportion of normal vaginal deliveries (n=62; 65.95%), followed by intravaginal dinoprostone (n=47; 56.63%), and intravenous oxytocin had the lowest rate (n=33; 42.85%). Cesarean section rates were greatest in the intravenous oxytocin group (n=31; 40.26%), followed by the intravaginal dinoprostone group (n=29; 34.94%), and lowest in the oral misoprostol group (n=24; 25.53%).

CONCLUSION

Oral misoprostol induces labor in women safely and effectively, resulting in the lowest percentage of cesarean deliveries and the highest percentage of normal vaginal deliveries, respectively. Intravaginal dinoprostone showed the lowest rate of side effects, followed by oral misoprostol while intravenous oxytocin had the highest rate of side effects.

Labor Induction with Intravaginal Misoprostol versus Spontaneous Labor: Maternal and Neonatal Outcomes

Purpose. To compare the maternal and neonatal outcomes of pregnant women who had labor induction with intravaginal misoprostol or had spontaneous labor in our clinic. Material-Method. The records of 213 pregnant women, who were followed up in Acibadem Maslak University Hospital for vaginal delivery between June 2021 and December 2021, were retrospectively evaluated. The pregnant women, who gave birth, were divided into 3 groups as follows: spontaneous labor (SL), those induced by a single dose of misoprostol (SDM), and those induced by multiple doses of misoprostol (MDM). The groups were compared in terms of delivery type, the vaginal birth rate within 12 hours, need for intervention, duration of the second stage of labor, cesarean section ratio due to fetal distress, time from the last dose to delivery, and 1st and 5th minute APGAR scores. Results. Among the primiparous pregnant women, 84.7% of SL group, 65.2% of SDM group, and 37% MDM group delivered vaginally within 12 hours ( $p<0.05$ ). The time from the last misoprostol dose to delivery was also statistically significantly shorter in pregnant women, who received a single dose of misoprostol (483 vs. 720 min, respectively). When the hospitalization time was evaluated, in the SDM group, the MDM group, and the SL group, it was found to be 611, 831, and 379 min, respectively. In multiparous pregnant women, the hospitalization time was 735 min in the SDM group, 494 min in the MDM group, and 261.5 min in the SL group ( $p<0.05$ ). Other than the hospitalization time, when the aforementioned variables were studied in multiparous pregnant women, no statistically significant difference among groups was observed ( $p>0.05$ ). Conclusion. Intravaginal misoprostol seems to be a promising medical agent for labor induction due to its high delivery rates within 12 hours and the absence of negative fetal outcomes, its ease of storage, and affordable cost.

Outpatient Compared With Inpatient Preinduction Cervical Ripening Using a Synthetic Osmotic Dilator: A Randomized Clinical Trial

OBJECTIVE

To assess whether outpatient cervical ripening with a synthetic osmotic dilator shortens the length of hospital stay in term pregnancies undergoing labor induction.

METHODS

Pregnant participants scheduled for labor induction at term with unfavorable cervix (less than 3-cm dilated and less than 60% effaced) and not requiring inpatient maternal or fetal monitoring were consented, and synthetic osmotic dilator rods were inserted on the day of scheduled induction. After reassuring fetal heart tracing, patients randomized to the outpatient group were asked to return 12 hours after insertion or sooner if needed. Those randomized to the inpatient group remained in the hospital. After the first round of ripening, additional ripening, oxytocin, and labor management were left up to the clinical health care professionals. The primary outcome was the proportion of participants with hospital stays longer than 48 hours. We estimated that a sample size of 338 would provide 85% power to detect a 30% difference between groups.

RESULTS

From November 2018 to November 2021, 339 participants were randomized (171 inpatient, 167 outpatient, one withdrawal). Four patients in the outpatient group were admitted before12 hours for suspected labor and rupture of membranes, and 19 in the inpatient group had the device removed before 12 hours. The proportion of participants with hospital stays longer than 48 hours was lower in the outpatient group compared with the inpatient group (89 [53%] vs 152 [89%], relative risk [RR] 0.60, 95% CI 0.52-0.70). Patients in the outpatient group had a shorter total length of stay and time from admission to active labor. They were more likely to have a vaginal delivery within 24 hours of admission and were less likely to receive analgesics during ripening. Route of delivery and other maternal and neonatal outcomes were not significantly different between groups.

CONCLUSION

Outpatient cervical ripening with a cervical osmotic dilator decreased hospital stay compared with inpatient ripening, without significant adverse outcomes.

FUNDING SOURCE

Medicem Technology s.r.o., Czech Republic.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT03665688.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

A snapshot of women’s and clinicians’ perceptions of the double balloon catheter for induction of labor

INTRODUCTION

Induction of labor (IOL) is rising globally and is growing steadily in the state of New South Wales, Australia. There are numerous methods of induction of labor, including the double balloon catheter (DBC). There is minimal evidence on women’s attitudes and experiences and clinician’s opinions on the use of the DBC. This study aims to explore the views regarding DBC insertion and effectiveness from women induced with a DBC and clinicians involved in the catheter insertion and care.

METHODS

This study is a descriptive survey of two prospective, de-identified, self-reported questionnaires which were completed in 2016. One questionnaire was administered to term pregnant women that were admitted to the antenatal ward post IOL, and the other was completed by midwives and obstetric doctors working in the ward at the time.

RESULTS

The DBC appeared to be a well-accepted method of cervical ripening among women (61%) and clinicians (>82%). Success of DBC to achieve an artificial rupture of membrane post removal, directly correlates to women’s acceptance (61%). While most clinicians (59–67%) perceived insertion of DBC in an outpatient setting and then women discharged home was appropriate, only 13% of women were in favor. On the logistics of the procedure in respect to insertion and removal of the DBC, there were differences of opinion, with only 43% of women, 77% of midwives and 33% of doctors stating that the timing of insertion and removal needed to be improved.

CONCLUSIONS

This study highlights the need to undertake qualitative research to further explore women’s views and perceptions on IOL in order to ensure that clinical practice is woman-centered and evidenced-based, and to guide policy and protocol.

Mechanical dilatation of the stenosed cervix under local anesthesia: A prospective case series

AIM

Cervical stenosis is traditionally managed by mechanical dilatation under general anesthesia (GA). We aimed to assess the safety, effectiveness, and patient acceptability of dilatation in the outpatient setting under local anesthesia (LA).

METHODS

Data were collected prospectively from all patients attending the outpatient department with cervical stenosis from March 20, 2015 to September 23, 2020. Mechanical dilatation of the cervix was performed using Hegar dilators under LA. Subsequent colposcopic assessment, cytology, histology, and management were recorded.

RESULTS

One hundred forty-nine cases were referred for cervical dilatation, 63 (43%) of which had complete stenosis. One hundred eighteen (79%) patients had previously undergone cervical procedures. Successful dilatation under LA was achieved in 119 (83%) patients; 5 (3%) declined (requesting GA), 6 (4%) did not tolerate speculum examination, and 19 (13%) had unsuccessful procedures. The median Hegar size used was 8 mm. Dilatation under LA was acceptable in 93% attempted procedures. Thirteen episodes of restenosis were recorded with no major adverse events. Younger age (p = 0.045) and severe (compared to complete) stenosis (p < 0.0001) were associated with procedure success, with improved results over time (p = 0.003). Successful dilatation permitted cervical assessment; eight patients required cervical excisions, two underwent hysterectomies, with one confirmed case of adenocarcinoma.

CONCLUSION

Rigid cervical dilatation in the outpatient setting provides effective, instantaneous treatment for women who have failed cytological or colposcopic assessment. For the vast majority of women, the procedure was well tolerated and preferred to using GA. However, given that 1 in 10 women experienced restenosis, patients should be counseled about the possibility of requiring further management.

A new technique for emergency cerclage: Guard suture method

Objective The aim of this study was to introduce a novel technique to treat midtrimester cervical insufficiency with prolapsed membranes. Material and methods This retrospective study included patients with singleton pregnancies between 16 and 28 gestational weeks that underwent emergency cervical cerclage in a tertiary center. Patients were divided into two groups as McDonald method and guard suture method group according to the procedure they underwent. The following variables were recorded and evaluated: gestational age at cerclage, cervical length between the suture and external cervical os measured by transvaginal ultrasound on postoperative 1st and 7th day, gestational age at delivery, time between the procedure and delivery, intraoperative complications, newborn intensive care unit (NICU) admission, Apgar scores of neonates, and discharged alive newborns. Results During the study period, 38 patients underwent emergency cerclage procedure. Twenty-three were included in the McDonald group and 15 were in the guard suture group. The mean gestational age at the time of cerclage was 22.1 (17 -27) weeks and the mean gestational age at delivery was 33.9 (26- 38) weeks. Prolongation time between cerclage and delivery was 80.42 (1 - 140) days. Significantly higher 1st and 5th minutes Apgar scores and significantly lower NICU admission was found in the guard suture group (p = 0.04, p = 0.01 and p = 0.02, respectively). Conclusion In cases with cervical insufficiency and prolapsed membranes, emergency cerclage may prevent premature birth by prolonging pregnancy. Guard suture method is safe, effective, and easily applicable and can help obstetricians achieve better fetal and neonatal outcomes.

Induction of labor using Foley catheter with weight attached versus without weight attached: A randomized control trial

OBJECTIVE

To assess the effectiveness in preventing cesarean section for failed induction by using Foley catheter for cervical ripening in comparison to Foley catheter with a weight attached to it.

METHODS

A randomized control trial conducted between November 2018 and July 2020, which looked at induction of labor with 30-ml Foley catheter in one arm and the Foley placed with a 500 ml weight attached to it in the other arm. Primary outcome was the cesarean section rate.

RESULTS

We randomized 399 women. Modes of delivery were similar in both groups. Numbers undergoing cesarean section for failed induction were higher in the group that underwent induction with Foley with weight but this was not statistically significant (45.7% vs 26.5%, P = 0.1). There was a shorter time to expulsion of the Foley with weight attached (mean ± standard deviation: 2.6 ± 3.3 h vs 10.9 ± 3.2 h, P < 0.001) but this did not translate into a difference in time to active labor or time to delivery.

CONCLUSION

Placing a weight at the end of the Foley catheter for induction of labor does not affect the time to delivery or the rate of cesarean deliveries, although there is faster expulsion of the Foley. Clinical trial registration no.: CTRI/2018/10/016154.

Foley Bulb Insertion by Blind Placement Compared With Direct Visualization: A Randomized Controlled Trial

OBJECTIVE

To test the hypothesis that digital placement of a balloon catheter is not inferior to the speculum method in terms of rate of maternal infection.

METHODS

In an open-label noninferiority randomized trial, pregnant women who were undergoing induction of labor with unfavorable cervix (less than 3 cm dilated and less than 60% effaced) were randomly assigned to balloon catheter that was placed either digitally or using a sterile speculum. The primary outcome was a composite of maternal infection, defined by occurrence of fever (temperature 38°C or higher), chorioamnionitis, or endometritis (diagnoses were made by the managing obstetric physician or midwife). Prespecified secondary outcomes included outcomes in the primary composite, cesarean delivery rates, and maternal and neonatal outcomes. A patient satisfaction survey was also obtained. On the basis of a noninferiority margin of 10% and an expected primary outcome frequency of 10%, a sample size of 372 women was needed (90% power to confirm noninferiority with 90% protocol adherence).

RESULTS

From February 2018 through February 2019, 372 women were randomized (185 digital placement, 187 sterile speculum). Baseline characteristics were similar between groups. The composite maternal infection rate was not different between groups (digital placement arm: 15.7% vs speculum arm: 12.8%), with an absolute difference with respect to the sterile speculum arm of 2.8% (95% CI -4.3 to 9.9%), indicating noninferiority for the prespecified margin. Secondary outcomes were not different between groups, except for a higher need for a second balloon catheter in the sterile speculum arm. Maternal and neonatal adverse events were not different between groups. Irrespective of method of placement, women were equally satisfied with the explanation of the method before placement, anxiety regarding the procedure, and pain during placement. More women in the sterile speculum group would choose the digital placement method for the subsequent pregnancy (37.6% vs 25.7%; P=.02.).

CONCLUSION

Digital placement of a balloon catheter for preinduction cervical ripening is noninferior to the sterile speculum method, in terms of maternal infection. Women in the sterile speculum group more frequently required a second round of the mechanical dilator. The blind digital approach is a reasonable option for balloon placement for cervical ripening.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT03450408.

Outpatient Induction of Labor - Are Balloon Catheters an Appropriate Method?

As the number of labor inductions in high-income countries has steadily risen, hospital costs and the additional burden on obstetric staff have also increased. Outpatient induction of labor is therefore becoming increasingly important. It has been estimated that 20 - 50% of all pregnant women requiring induction would be eligible for outpatient induction. The use of balloon catheters in patients with an unripe cervix has been shown to be an effective and safe method of cervical priming. Balloon catheters are as effective as the vaginal administration of prostaglandin E 2 or oral misoprostol. The advantage of using a balloon catheter is that it avoids uterine hyperstimulation and monitoring is less expensive. This makes balloon catheters a suitable option for outpatient cervical ripening. Admittedly, intravenous administration of oxytocin to induce or augment labor is required in approximately 75% of cases. Balloon catheters are not associated with a higher risk of maternal and neonatal infection compared to vaginal PGE 2 . Low-risk pregnancies (e.g., post-term pregnancies, gestational diabetes) are suitable for outpatient cervical ripening with a balloon catheter. The data for high-risk pregnancies are still insufficient. The following conditions are recommended when considering an outpatient approach: strict selection of appropriate patients (singleton pregnancy, cephalic presentation, intact membranes), CTG monitoring for 20 - 40 minutes after balloon placement, the patient must be given detailed instructions about the indications for immediate readmission to hospital, and 24-hour phone access to the hospital must be ensured. According to reviewed studies, the balloon catheter remained in place between 12 hours ("overnight") and 24 hours. The most common reason for readmission to hospital was expulsion of the balloon catheter. The advantages of outpatient versus inpatient induction of cervical ripening with a balloon catheter were the significantly shorter hospital stay, the lower costs, and higher patient satisfaction, with both procedures having been shown to be equally effective. Complication rates (e.g., vaginal bleeding, severe pain, uterine hyperstimulation syndrome) during the cervical ripening phase are low (0.3 - 1.5%); severe adverse outcomes (e.g., placental abruption) have not been reported. Compared to inpatient induction of labor using vaginal PGE 2 , outpatient cervical ripening using a balloon catheter had a lower rate of deliveries/24 hours and a significantly higher need for oxytocin; however, hospital stay was significantly shorter, frequency of pain during the cervical ripening phase was significantly lower, and patients' duration of sleep was longer. A randomized controlled study comparing outpatient cervical priming with a balloon catheter with outpatient or inpatient induction of labor with oral misoprostol would be of clinical interest.

MEchanical DIlatation of the Cervix-- in a Scarred uterus (MEDICS): the study protocol of a randomised controlled trial comparing a single cervical catheter balloon and prostaglandin PGE2 for cervical ripening and labour induction following caesarean delivery

INTRODUCTION

Labour induction in women with a previous caesarean delivery currently uses vaginal prostaglandin E2 (PGE2), which carries the risks of uterine hyperstimulation and scar rupture. We aim to compare the efficacy of mechanical labour induction using a transcervically applied Foley catheter balloon (FCB) with PGE2 in affected women attempting trial of labour after caesarean (TOLAC).

METHODS AND ANALYSIS

This single-centre non-inferiority prospective, randomised, open, blinded-endpoint study conducted at an academic maternity unit in Singapore will recruit a total of 100 women with one previous uncomplicated caesarean section and no contraindications to vaginal delivery. Eligible consented participants with term singleton pregnancies and unfavourable cervical scores (≤5) requiring labour induction undergo stratified randomisation based on parity and are assigned either FCB (n=50) or PGE2 (n=50). Treatments are applied for up to 12 hours with serial monitoring of the mother and the fetus and serial assessment for improved cervical scores. If the cervix is still unfavourable, participants are allowed a further 12 hours' observation for cervical ripening. Active labour is initiated by amniotomy at cervical scores of ≥6. The primary outcome is the rate of change in the cervical score, and secondary outcomes include active labour within 24 hours of induction, vaginal delivery, time-to-delivery interval and uterine hyperstimulation. All analyses will be intention-to-treat. The data generated in this trial may guide a change in practice towards mechanical labour induction if this proves efficient and safer for women attempting TOLAC compared with PGE2, to improve labour management in this high-risk population.

ETHICS AND DISSEMINATION

Ethical approval is granted by the Domain Specific Review Board (Domain D) of the National Healthcare Group, Singapore. All adverse events will be reported within 24 hours of notification for assessment of causality. Data will be published and will be available for future meta-analyses.

TRIAL REGISTRATION NUMBER

NCT03471858; Pre-results.

Immediate dilation of a tight or stenotic cervix by intra-procedural administration of hyoscine butylbromide: A clinical trial

Background

Cervical dilation is indicated prior to performing various gynecological procedures. However, gynecologists are at times confronted with a stenotic or tight cervix, resistant to dilation. This can be problematic particularly when cervical ripening has not been attempted hours before the start of the procedure.

Objective

The objective of this study is to investigate the efficacy of administration of hyoscine butylbromide for cervical dilation for immediate dilation of the tight or stenotic cervix.

Materials and Methods

In this clinical trial study, a population of 40 women, aged 20-70 yr with stenotic cervix, evidenced by resistance to pass dilator #2 through their cervical canal were compared. Cervical patency was assessed 10 min following intra-cervical canal instillation of hyoscine butylbromide.

Results

Cervical width of 57.5% of patients became wider, as evidenced by passage of the number 4 Hegar dilator through the cervical canal without resistance. Independent T-tests did not reveal any statistically significant difference between the two groups based on their age. Fisher Exact test revealed a statistically significant difference between the two groups based on the prior route of delivery, with a more statistically significant response in patients who had vaginal deliveries.

Conclusion

Intra-cervical canal instillation of hyoscine butylbromide is effective in immediate dilation of the tight or stenotic cervix during intra-uterine procedures.

Efficacy of the mini-meatoplasty

OBJECTIVES

The lateral meatoplasty is a well-described technique for widening the lateral external auditory meatus. After bony canalplasty, the external auditory meatus may need to be enlarged to accommodate an expanded tympanic ring. In this study, we introduce a novel meatoplasty technique for use during canalplasty and describe its efficacy in widening the external auditory meatus.

METHODS

Patients undergoing at least 180-degree bony canalplasty and mini-meatoplasty at a tertiary care facility were enrolled. Meatus diameter was measured before and after mini-meatoplasty using Shea aural speculums and Hegar dilators.

RESULTS

Nineteen patients were enrolled. Mean preoperative speculum size was 6.1 mm (range 3.5-7.5 mm). All postoperative speculum sizes were 8 mm (P < .0001). Mean preoperative and postoperative Hegar dilator sizes were 10.6 mm (range 7-14 mm) and 16.2 mm (range 13-19 mm), respectively (P < .0001). The mean increase in aural speculum and Hegar dilator sizes were 1.9 mm (range 0.5-3.5 mm) and 5.7 mm (range 3-10 mm), respectively (P < .0001).

CONCLUSIONS

The mini-meatoplasty is a novel and effective technique for widening the external auditory meatus after bony canalplasty.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:1294-1298, 2020.

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

Comparison of single- and double-balloon catheters for labor induction: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

There is a paucity of head-to-head randomized trials that compare single- and double-balloon catheters, and the results of the available data in terms of time from catheter insertion to delivery and delivery mode are mixed. This meta-analysis of randomized controlled trials compares the efficacy of single- and double-balloon catheters in women undergoing labor induction.

STUDY DESIGN

Searches were made in MEDLINE, EMBASE, PubMed, ClinicalTrials.gov, and the Cochrane Library from inception through June 2016. Peer-reviewed randomized and quasi-randomized trials that compared single- and double-balloon catheters head-to-head for cervical ripening or labor induction were identified. Eligible study populations consisted of women with singleton pregnancies that had any indication for labor induction and were randomly assigned to undergo induction with a single- or a double-balloon catheter. The primary outcome was time from catheter insertion to delivery and delivery mode. The secondary outcomes were intrapartum fever or chorioamnionitis, woman's satisfaction, and neonatal Apgar score.

RESULTS

Of the 520 records identified, five randomized trials (996 women; 491 with single-balloon and 505 with double-balloon catheters) were considered eligible and included in the meta-analysis. Time from catheter insertion to delivery did not differ between the two types of catheter (p = 0.527; WMD -0.87; 95% CI: -3.55, 1.82). The incidence of cesarean delivery also did not differ (p = 0.844; RR 0.97; 95% CI: 0.69, 1.35). Delivery within 24 h, delivery mode, incidences of intrapartum fever or chorioamnionitis, and neonatal Apgar score <7 at 5 min did not differ between the two types of catheter as well. Women who were induced with the single-balloon catheter were more satisfied (p = 0.029; WMD 0.56; 95% CI: 0.06, 1.06).

CONCLUSION

Time from catheter insertion to delivery and delivery mode were comparable between the two types of catheter.

A prospective randomized trial comparing Foley catheter, oxytocin, and combination Foley catheter-oxytocin for labour induction with unfavourable cervix

The purpose of this study was to evaluate the effectiveness and safety of transcervical Foley catheter with and without oxytocin versus oxytocin alone for labour induction with unfavourable cervix. This trial enrolled 108 women with singleton pregnancies presented for labour induction with unfavourable cervix. Patients were randomly assigned to receive Foley catheter alone (I), Foley catheter plus oxytocin (II) or oxytocin alone (III). Outcomes were analysed in terms of success of induction, induction delivery interval, route of delivery, dose and duration of oxytocin, and complications. Successful normal vaginal delivery was more common in group I (p = .02) compared to group III. Induction delivery time was statistically shorter in group II and group III (p < .001). Patients in group I required significantly less oxytocin dose and duration (p < .001). This led to our conclusion that induction of labour with Foley catheter without oxytocin increases success rate of normal vaginal delivery; however, it has a longer induction delivery interval with similar complications.

Risk of caesarean delivery after induction of labour stratified by foetal sex

This study describes a retrospective analysis of all women admitted for induction of labour (IoL), carrying a viable singleton foetus, after 34 + 0 weeks of gestation. We aimed to evaluate if foetal sex has an impact on the rate of caesarean delivery following labour induction. Our results demonstrate that among the 1062 women who met the inclusion criteria, 49% (521/1062) were carrying a male foetus. Other than a lower rate of Oxytocin use for the female sex pregnancies, there were no significant differences in pre-labour and labour characteristics between male or female sex pregnancies. There was no difference in caesarean delivery rate between groups (14.4% vs. 14.2%, male vs. female, respectively, p = .505). We concluded conclude that foetal sex does not impact the caesarean delivery rate among women undergoing IoL, regardless of the indication for induction and the indication for the caesarean delivery. Impact statement Male sex foetuses are at increased risk for adverse perinatal outcomes including, among others, an increased risk for caesarean delivery. The possible contribution of male sex to caesarean delivery after labour induction has not been specifically explored. Following induction of labour, there is no difference in failed induction or caesarean delivery rate between male and female sex pregnancies. Induction of labour may be safely employed for both male and female foetuses.

Induction of labor in elderly nulliparous women

PURPOSE

Maternal age is an important consideration for antenatal care, labor and delivery. We aimed to evaluate the induction of labor (IoL) failure rates among elderly nulliparous women.

MATERIALS AND METHODS

We conducted a retrospective analysis of all nulliparous women at 34 + 0 to 41 + 6 weeks, undergoing cervical ripening by prostaglandin E2 (PGE2) vaginal insert. Study group included elderly (≥35 years) nulliparous and control group included non-elderly (<35 years) nulliparous women. Primary outcome was IoL failure rate and secondary outcome was cesarean delivery rate. Outcomes were compared between the groups by univariate analysis followed by regression analysis to adjust results to potential confounders.

RESULTS

Of 537 women undergoing IoL, 69 (12.8%) were elderly. The univariate analysis demonstrated no difference in IoL failure rate (26.5% versus 34.8%, p = 0.502) between groups. However, elderly nulliparous women had higher rates of cesarean delivery (36.2% versus 21.4%, p = 0.009). This difference was no longer significant after adjustment for maternal body mass index, indication for delivery, birth weight and gestational age at delivery.

CONCLUSION

Among nulliparous women, older maternal age is not associated with higher rates of IoL failure or cesarean deliveries.

Foley catheter placement for induction of labor with or without stylette: a randomized clinical trial

BACKGROUND

Foley catheters are used for cervical ripening during induction of labor. Previous studies suggest that use of a stylette (a thin, rigid wire) to guide catheter insertion decreases insertion failure. However, stylette effects on insertion outcomes have been sparsely studied.

OBJECTIVE

The purpose of this study was to compare catheter insertion times, patient-assessed pain levels, and insertion failure rates between women who received a digitally placed Foley catheter for cervical ripening with the aid of a stylette and women who received the catheter without a stylette.

STUDY DESIGN

We conducted a randomized clinical trial of women aged ≥ 18 years who presented for induction of labor. Inclusion criteria were singletons with intact membranes and cephalic presentation. Women received a computer-generated random assignment of a Foley catheter insertion with a stylette (treatment group, n = 62) or without a stylette (control group, n = 61). For all women, a standard insertion technique protocol was used. Three primary outcomes were of interest, including the following: (1) insertion time (total minutes to successful catheter placement), (2) patient-assessed pain level (0-10), and (3) failure rate of the randomly assigned insertion method. Treatment control differences were first examined using the Pearson's test of independence and the Student t test. Per outcome, we also constructed 4 regression models, each including the random effect of physician and fixed effects of stylette use with patient nulliparity, a history of vaginal delivery, cervical dilation at presentation, or postgraduate year of the performing resident physician.

RESULTS

Women who received the Foley catheter with the stylette vs without the stylette did not differ by age, race/ethnicity, body mass index, or any of several other characteristics. Regression models revealed that insertion time, patient pain, and insertion failure were unrelated to stylette use, nulliparity, and history of vaginal delivery. However, overall insertion time and failure were significantly influenced by cervical dilation, with insertion time decreasing by 21% (95% confidence interval [CI], 5-34%) and odds of failure decreasing by 71% (odds ratio, 0.29; 95% CI, 0.10-0.86) per 1 cm dilation. Resident postgraduate year also significantly influenced insertion time, with greater time required of physicians with less experience. Mean insertion time was 51% (95% CI, 23-69%) shorter for fourth-year than second-year residents. Statistically nonsignificant but prominent patterns in outcomes were also observed, suggesting stylette use may lengthen the overall insertion procedure but minimize variability in pain levels and decrease insertion failure.

CONCLUSIONS

The randomized trial suggests that, even after accounting for nulliparity, history of vaginal delivery, cervical dilation, and physician experience, Foley catheter insertions with and without a stylette are equivalent in insertion times, patient pain levels, and failure of catheter placement.

Analysis of cervical resistance during continuous controllable balloon dilatation: controlled clinical and experimental study

Background

Hydraulic dilatation is a novel method of cervical dilatation that is based on continuous controllable dilatation (CCBD) by the pumping of fluid into the balloon extension of the system. The main advantage of this procedure is that it allows control of and insight into the process of cervical dilatation.

Methods

For the purposes of our research, we created a new and upgraded system for CCBD which consists of a programmed hydrostatic pump connected to a balloon extension. With regard to our aim to precisely measure and determine the location of the cervical resistance, we placed two pressure-measuring films, one on the top and one on the bottom of the balloon extension. This study included 42 patients in whom cervical resistance was measured before suction curettage.

Results

Cervical dilatation and measurement of cervical resistance were successful in all patients. The analysis of the pressure-measuring films showed that the points of highest resistance were located in the zone of the internal cervical os and that these values were much higher than those in the zone of the external cervical os (0.402 versus 0.264 MPa at the upper pressure-sensitive film; 0.387 versus 0.243 MPa at the lower pressure-sensitive film). This study also showed that an increase in cervical resistance in the zone of the internal cervical os was followed by an increase in cervical resistance in the zone of the external cervical os.

Conclusions

During CCBD, the internal cervical os is the centre of cervical resistance, and the values do not decline with the number of miscarriages or the number of previous births.

Trial registration number

ISRCTN Registry identifier: ISRCTN30949871. Date of registration: 13 May 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-015-1003-8) contains supplementary material, which is available to authorized users.

Other mechanical methods for pre-induction cervical ripening

Pre-induction cervical ripening is an important part of the labor induction process in women with an unfavorable cervix. This can be achieved either by pharmacologic or mechanical methods of cervical ripening. While the Foley catheter is the most commonly used mechanical method for labor induction, other mechanical methods are also available. This article reviews the safety profiles of osmotic dilators, extra-amniotic saline infusion, double-balloon catheters, and also compares their efficacy to that of other mechanical and pharmacologic cervical ripening methods. While mechanical methods have been shown to be safe and effective for cervical ripening, none of these alternatives has been shown to be superior to the Foley catheter.

Cervical ripening with the balloon catheter and the risk of subsequent preterm birth

OBJECTIVE

To examine the risk of subsequent preterm birth after cervical ripening using a balloon catheter.

STUDY DESIGN

A retrospective study was held at a university teaching hospital between January 2007 and June 2013. The study group included women who underwent cervical ripening using a balloon (single or double) catheter in the previous pregnancy followed by a subsequent singleton delivery (balloon catheter group). Two control groups were included. The first was similar to the study group except that ripening was achieved in the previous pregnancy with vaginal prostaglandin E2 (PGE2 group). The second control group had a previous pregnancy that resulted in spontaneous onset of labor at term (unexposed group). The primary outcome was the incidence of spontaneous preterm birth (before 37 weeks) in the index pregnancy.

RESULT

Overall, 558 women were included; each group consisted of 186 women. The incidence of spontaneous preterm birth in the index pregnancy did not differ between the groups (0.5, 1.6 and 2.7% in the balloon catheter, PGE2 and in the unexposed groups, respectively, P=0.31). Among the balloon catheter group, 58 (31.2%) women had the ripening performed with a single-balloon catheter and 128 (68.8%) women with a double-balloon catheter. The rate of the spontaneous preterm birth in the index pregnancy did not differ between the two groups (P=1.0).

CONCLUSION

Cervical ripening with a balloon catheter does not increase the rate of subsequent spontaneous preterm birth.

Mechanical labor induction in the obese population: a secondary analysis of a prospective randomized trial

OBJECTIVE

The objective of this study was to estimate the influence of maternal body mass index (BMI) on progress and outcomes of labor induction using mechanical devices.

METHODS

This study was a secondary analysis of data collected during the Cook Catheter vs. Foley Catheter study, a series of prospective randomized trials of women requiring cervical ripening for labor induction. The duration, characteristics, and outcomes of labor were analyzed after stratification by BMI categories. Outcomes assessed included time from device insertion to delivery, successful ripening, cesarean delivery rates, and any maternal and neonatal adverse events.

RESULTS

One hundred and eighty-one patients were stratified according to BMI categories, with 102 study participants classified as normal weight (BMI ≤30) and 79 as obese (BMI >30). Maternal satisfaction from the induction process was significantly lower in the obese group compared to the normal weight group (5.95 ± 3.14 vs. 7.58 ± 2.7, respectively, in a 1-10 scale, p = 0.009). The cesarean delivery rate was similar in the normal weight and the obese groups (17.6 vs. 25.3 %, respectively, p = 0.27). No statistical differences were found in all other outcomes evaluated, including a sub-analysis of the different mechanical devices.

CONCLUSIONS

During the process of mechanical cervical ripening, maternal satisfaction, but not objective obstetrical parameters, was influenced by increased maternal BMI. The trial is registered at ClinicalTrials.gov, no: NCT00604487. Trial registry name is "Induction of Labor in Patients with Unfavorable Cervical Conditions."

The effect of a Foley catheter balloon on cervical ripening

The Foley catheter balloon may affect cervical ripening through changes in biochemical mediators by immunoassay and immunohistochemistry, when it is used for pre-induction cervical ripening. The aim of the study was to evaluate the changes in the biochemical mediators from the extra-amniotic space and immunohistochemistry in ripened cervical tissue after the insertion of a Foley catheter balloon (FCB) for pre-induction cervical ripening. A total of 18 pregnant women with a Bishop's score < 6, who were undergoing labour induction, were evaluated in this prospective study. The FCB was irrigated with 10 ml of phosphate buffered saline and the irrigant was collected 0, 2, 4 and 8 h after placement of the FCB or until spontaneous expulsion of the FCB occurred. Irrigant specimens were also collected from 10 spontaneous labouring (SL) women in the active phase of labour. The levels of interleukin (IL)-6, IL-8, matrix metalloproteinase (MMP)-8 and NO were measured. Cervical specimens were obtained from 12 women, including four undergoing induction; four SL and four non-pregnant (NP) women. Immunohistochemical staining was performed to localise hyaluronic acid synthase (HAS)-1, IL-6, IL-8, MMP-8, endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS). Results showed that the levels of IL-6, IL-8, and MMP-8 significantly increased over time in FCB group (p < 0.01). In the immunohistochemical analysis of cervical tissues, immunoreactivity of HAS-1 in the after FCB group was stronger than any of the other groups. The protein expressions of IL-6, IL-8, MMP-8, eNOS and iNOS were more prominent in the after FCB and SL groups than in the NP and the before FCB groups. iNOS was only observed in the after FCB and SL groups. It was concluded that FCB may affect cervical ripening through changes in biochemical mediators by immunoassay and immunohistochemistry, when it is used for pre-induction cervical ripening.

Trans-cervical double balloon catheter with and without extra-amniotic saline infusion for cervical ripening: a prospective quasi-randomized trial

OBJECTIVE

To compare the efficacy and safety of the trans-cervical double balloon catheter with and without extra-amniotic saline infusion (EASI) for cervical ripening.

METHODS

This is a secondary analysis of a prospective randomized study conducted between November 2007 and January 2011 evaluating different ripening methods. Women presenting for labor induction were assigned to receive the double balloon catheter with (study group) or without EASI (control group). Outcomes included time from device insertion to delivery, cesarean section rates, and adverse events.

RESULTS

One hundred and sixty women completed the study. Cesarean section rate (8.3% in study group, versus 20% in controls p = 0.07) and ripening success were comparable between the groups. Catheter insertion to delivery interval was significantly shorter and spontaneous catheter expulsion rate was significantly higher in the study group (14:19 hours versus 20:45 hours, p < 0.001, and 68.5% versus 51%, p = 0.04, respectively). Hospitalization length was significantly shorter in the study arm. There were no differences in other outcomes evaluated. A multivariable analysis found the EASI to be an independent predictor of a shorter insertion to delivery interval.

CONCLUSIONS

The addition of EASI to the double balloon catheter for cervical ripening results in a shorter labor induction process without compromising its safety.

Making cervical ripening EASI: a prospective controlled comparison of single versus double balloon catheters

OBJECTIVE

To compare the efficacy of two mechanical devices for cervical ripening: double versus single balloon catheters, both with extra-amniotic saline infusion (EASI).

METHODS

Women at term with a singleton pregnancy presenting for labor induction were assigned to receive the double balloon catheter (with EASI) or the single balloon catheter (with EASI). Outcomes included time from device insertion to delivery, rates of successful vaginal delivery and occurrence of adverse events.

RESULTS

One hundred and eighty-six women completed the study. Ripening success was comparable between the double and single balloon arms (96.4% versus 92.7%, p = 0.55, respectively). Balloon insertion to delivery interval was significantly shorter, and cesarean section rate was significantly lower in the double balloon arm compared with the single balloon arm (14.3 versus 15.8 h, p = 0.04 and 8.3% versus 20%, p = 0.05, respectively). There were no significant differences in maternal characteristics, satisfaction or adverse outcomes.

CONCLUSIONS

This study is the first documented assessment of the double balloon catheter combined with EASI. Our findings suggest that the double balloon catheter results in reduced time to delivery and higher vaginal delivery rates, compared with the single balloon catheter with EASI, without compromising maternal or fetal safety.

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

The efficacy of early amniotomy in nulliparous labor induction: a randomized controlled trial

OBJECTIVE

The purpose of this study was to assess whether early amniotomy reduces the duration of labor or increases the proportion of subjects who are delivered within 24 hours in nulliparous patients who undergo labor induction.

STUDY DESIGN

We performed a randomized controlled trial that compared early amniotomy to standard management in nulliparous labor inductions. Inclusion criteria were nulliparity, singleton, term gestation, and a need for labor induction. Subjects were assigned randomly to early amniotomy (artificial rupture of membranes, ≤4 cm) or to standard treatment. There were 2 primary outcomes: (1) time from induction initiation to delivery and (2) the proportion of women who delivered within 24 hours.

RESULTS

Early amniotomy shortens the time to delivery by >2 hours (19.0 vs 21.3 hours) and increases the proportion of induced nulliparous women who deliver within 24 hours (68% vs 56%). These improvements in labor outcomes did not come at the expense of increased complications.

CONCLUSION

Early amniotomy is a safe and efficacious adjunct in nulliparous labor inductions.

Continuous controllable balloon dilation: a novel approach for cervix dilation

Background

Cervical dilation using mechanical dilators is associated with various complications, such as uterine perforation, cervical laceration, infections and intraperitoneal hemorrhage. To achieve safe and painless cervical dilation, we constructed a new medical device to achieve confident mechanical cervical dilation: a continuous controllable balloon dilator (CCBD).

Methods

Controlled pumping of incompressible fluid into the CCBD increases the pressure and outer diameter of the CCBD, continuously dilating the cervical canal. The reliability of the CCBD was confirmed in vitro (testing for consistency and endurance, with no detected risk for breakage) and in vivo. A multi-center clinical study was conducted,with 120 pregnant women randomly assigned to one of three groups: Group I,control group, no dilation;Group II,mechanical dilation, Hegar dilator (HeD); and Group III,CCBD. The tissue material for histological evaluation was obtained from the endocervical mucosa before and after dilation using the HeD or CCBD.

Results

The CCBD dilations were successful and had no complications in all 40 patients of Group III. The cervical tissue was markedly less damaged after CCBD dilation compared with HeD dilation (epithelium damage: 95% (HeD) vs. 45% (CCBD), P <0.001; basal membrane damage: 82.5% (HeD) vs. 27.5% (CCBD), P <0.001; stromal damage: 62.5% (HeD) vs. 37.5% (CCBD), P <0.01). Cervical hemorrhagia was observed in 90% of the patients after HeD dilation versus in 32.5% of the patients after CCBD dilation.

Conclusions

The CCBD should be used as a replacement for mechanical dilators to prevent uterine and cervical injury during cervical dilation.

Trial registration

ISRCTN54007498

Current methods of labor induction

In 2009, approximately 23% of all pregnant women in the United States underwent induction of labor, which is more than double the incidence of 9.5% in 1990. The ultimate goal of labor induction is to achieve vaginal delivery by stimulating uterine contractions before the spontaneous onset of labor. Labor induction is clearly indicated when the benefits outweigh the maternal and fetal risks of continued gestation, as well as potential risks associated with the procedure. Many women undergoing labor induction require cervical ripening--a method to facilitate softening, thinning, and dilation of an unfavorable cervix--because it reduces the time to delivery and incidence of failed induction. This article summarizes currently available methods for labor induction and cervical ripening, advantages and disadvantages of various methods, and the safety and effectiveness of each method based on well-conducted clinical trials.