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

Preinduction cervical ripening in an outpatient setting: a prospective pilot study of a synthetic osmotic dilator compared with a double-balloon catheter

OBJECTIVES

To compare the effectiveness, safety and patient satisfaction of a double balloon catheter (DB) with a synthetic osmotic cervical dilator (OD) for pre-induction cervical ripening in an outpatient setting.

METHODS

This is a prospective, dual-center pilot study including 94 patients with an unripe cervix (Bishop Score <6) near term; 50 patients received the DB and 44 patients the OD. The primary outcomes were the difference in Bishop Score (BS) and cervical shortening. Pain perception at insertion and during the cervical ripening period was evaluated by a visual analogue scale and patient satisfaction by a predefined questionnaire.

RESULTS

The use of DB was associated with a significantly higher increase in BS (median 3) compared to OD (median 2; p=0.002) and resulted in significantly greater cervical shortening (median -14 mm vs. -9 mm; p=0.003). There were no serious adverse events at placement of devices or during the cervical ripening. There were no significant differences in perinatal outcomes. Pain perception during cervical ripening was significantly higher (p<0.001), and patient satisfaction regarding sleep, relaxing time and performing desired daily activities were significantly lower in patients with DB compared to patients with OD (p<0.001).

CONCLUSIONS

DB was superior to OD regarding cervical ripening based on BS and on sonographic measurement of the cervical length. Patients with OD experienced less pain during cervical ripening and were more satisfied with the method compared to patients with DB.

Outcome of induction of labour at 41 weeks with foley catheter in midwifery-led care

OBJECTIVE

Assess the outcome of induction of labour (IOL) with a Foley catheter in pregnancies at 41 weeks in midwifery-led care setting compared to consultant-led care setting.

DESIGN

Mixed-methods cohort study at a midwifery - hospital partnership in Amsterdam, the Netherlands.

SETTING AND PARTICIPANTS

Prospectively, women undergoing IOL in midwifery-led care were recruited at a secondary hospital. This group was compared to a retrospective cohort, in which IOL was exclusively performed under consultant-led care.

MEASUREMENTS AND FINDINGS

We compared 320 women whose induction started in midwifery-led care to a historical cohort of 320 women induced for the same reason under consultant-led care. Both groups exhibited similar rates of spontaneous vaginal births (64.2 %vs62.5 %). Caesarean section and assisted vaginal birth rates did not significantly differ. Maternal adverse outcomes were comparable, while neonatal adverse outcomes were significantly higher in the midwifery-led care group (8.1 %vs3.8 %; OR 2.27, 95 % CI 1.12-4.58). The use of pain relief was significantly lower in midwife-led care (65.3 %vs75.3 %; OR 0.62, 95 % CI 0.44-0.87). 20.6 % of births occurred in midwife-led care.

KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

In this single-centre study, spontaneous vaginal birth rates following IOL with a Foley catheter were similar between midwife- and consultant-led care. However, the midwife-led group showed a higher risk of adverse neonatal outcomes, mainly early onset neonatal sepsis, with a minority eventually delivering under midwife-led care. Implications highlight the need for broader research, validation across diverse settings and exploration of patient and healthcare worker perspectives to refine the evolving midwifery-led care model.

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.

The infection, cervical and perineal lacerations in relation to postpartum hemorrhage following vaginal delivery induced by Cook balloon catheter

OBJECTIVE

To identify whether infection, cervical laceration and perineal laceration are associated with postpartum hemorrhage in the setting of vaginal delivery induced by Cook balloon catheter.

MATERIALS AND METHODS

The retrospective study included 362 women who gave birth vaginally at or beyond 37 weeks of gestation with a diagnosis of postpartum hemorrhage between February 2021 to May 2022, of which including 216 women with induction of labor (Cook balloon catheter followed by oxytocin or oxytocin) and 146 women with spontaneous delivery. Risk factors for postpartum hemorrhage were collected and compared.

RESULTS

362 women were divided into three groups, group 1 with spontaneous delivery, group 2 with oxytocin, group 3 with Cook balloon catheter followed by oxytocin. There was no significant difference in incidence of infection within three groups (P > 0.05). The rate of cervical laceration and perineal laceration was significantly higher in group 3 compared with groups 2 and 1 (P < 0.05); Multivariate logistic regression analysis found that compared with group 1, either group 3 or group 2 was associated with increased risks of cervical laceration and perineal laceration (P < 0.05), and compared with group 2, group 3 was not associated with increased risks of cervical laceration and perineal laceration (P > 0.05).

CONCLUSION

Infection, cervical laceration and perineal laceration are identified not to be independent risk factors for postpartum hemorrhage for women undergoing labor with Cook balloon catheter; Cervical laceration and perineal laceration increase the risk of postpartum hemorrhage in women with labor induction.

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.

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 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.

Association between intracervical Foley balloon and clinical chorioamnionitis among patients with group B streptococcus colonization undergoing induction with standardized labor management

BACKGROUND

Intracervical Foley balloons are commonly used for cervical ripening, but there has been a historical concern regarding an increased risk of clinical chorioamnionitis with Foley balloon use in patients with group B streptococcus.

OBJECTIVE

This study aimed to determine whether intracervical Foley balloon use in patients with group B streptococcus is associated with an increased risk of clinical chorioamnionitis.

STUDY DESIGN

This was a secondary analysis of a randomized controlled trial Mechanical and Pharmacologic Methods of Labor Induction: A Randomized Controlled Trial that compared cervical ripening agents within a standardized labor protocol. Foley balloon (alone, with oxytocin, or with misoprostol) was compared with misoprostol only to evaluate the primary outcome of clinical chorioamnionitis, defined based on the American College of Obstetricians and Gynecologists guidelines. Patients with a term, singleton pregnancy with intact membranes and an unfavorable cervix (Bishop score of ≤6 and dilation ≤2 cm) and a known group B streptococcus status were included. The secondary outcomes included a composite postpartum maternal infectious outcome consisting of any occurrence of endometritis, wound infection, postpartum urinary tract infection, or maternal sepsis; additional secondary outcomes included neonatal outcomes. Binomial regression with robust error variance was used to evaluate whether group B streptococcus status modified the relationship between Foley balloon use and clinical chorioamnionitis and to adjust for confounders.

RESULTS

A total of 491 patients were enrolled in the original trial. Of these patients, 467 had a known group B streptococcus status and underwent cervical ripening: 182 (39.0%) had group B streptococcus, and 285 (61.0%) did not have group B streptococcus. Moreover, 73.0% of patients received a Foley balloon, and 27.0% of patients did not receive a Foley balloon. There was no difference in the demographic or clinical characteristics between groups. The overall rate of clinical chorioamnionitis was 12.2%, with no difference between those with and without a Foley balloon (12.6% vs 11.1%, respectively; P=.66). Group B streptococcus status did not modify the association between Foley balloon use and clinical chorioamnionitis (relative risk, 0.93; 95% confidence interval, 0.50-1.72). This remained unchanged after adjusting for gestational age (adjusted relative risk, 0.87; 95% confidence interval, 0.45-1.67). Furthermore, other maternal and neonatal outcomes were similar between groups.

CONCLUSION

In this secondary analysis of a large randomized trial using a standardized labor protocol, there was no increased risk of infectious morbidity with Foley balloon use in patients overall and in patients with group B streptococcus. Our findings support that a Foley balloon can be safely used for cervical ripening in patients with group B streptococcus colonization.

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.

Comparison of the effectiveness and pregnancy outcomes of labor induction with dinoprostone or single-balloon catheter in term nulliparous women with borderline oligohydramnios

BACKGROUNDS

At present, there is no consensus on the induction methods in term pregnancy with borderline oligohydramnios. This study aimed to compare the effectiveness and pregnancy outcomes of labor induction with dinoprostone or single-balloon catheter (SBC) in term nulliparous women with borderline oligohydramnios.

METHODS

We conducted a retrospective cohort study from January 2016 to November 2018. During the study period, a total of 244 cases were enrolled. Of these, 103 cases were selected for induction using dinoprostone and 141 cases were selected for induction with SBC. The pregnancy outcomes between the two groups were compared. Primary outcomes were successful vaginal delivery rates. Secondary outcomes were maternal and neonatal adverse events. Multivariate logistic regression was used to assess the risk factors for vaginal delivery failure in the two groups.

RESULTS

The successful vaginal delivery rates were similar between the dinoprostone group and the SBC group (64.1% [66/103] vs. 59.6%, [84/141] P = 0.475), even after adjustment for potential confounding factors (adjusted odds ratio [aOR]: 1.07, 95% confidence interval [CI]: 0.57-2.00, P = 0.835). The incidence of intra-amniotic infection was lower in the dinoprostone group than in the SBC group (1.9% [2/103] vs. 7.8%, [11/141] P < 0.001), but the presence of non-reassuring fetal heart rate was higher in the dinoprostone group than in the SBC group (12.6% [13/103] vs. 0.7%, [1/141] P < 0.001). Multivariate logistic regression showed that nuchal cord was a risk factor for vaginal delivery failure after induction with dinoprostone (aOR: 6.71, 95% CI: 1.96-22.95). There were three factors related to vaginal delivery failure after induction with SBC, namely gestational age (aOR: 1.51, 95% CI: 1.07-2.14), body mass index (BMI) >30 kg/m2 (aOR: 2.98, 95% CI: 1.10-8.02), and fetal weight >3500 g (aOR: 2.49, 95% CI: 1.12-5.50).

CONCLUSIONS

Term nulliparous women with borderline oligohydramnios have similar successful vaginal delivery rates after induction with dinoprostone or SBC, with their advantages and disadvantages. In women with nuchal cord, the risk of vaginal delivery failure is increased if dinoprostone is used in the induction of labor. BMI >30 kg/m2, large gestational age, and estimated fetal weight >3500 g are risk factors for vaginal delivery failure after induction with SBC.

Mechanical Methods for the Induction of Labour After Previous Caesarean Section – An Updated, Evidence-based Review

There are currently no up-to-date evidence-based recommendations on the preferred method to induce labour after previous Caesarean section, especially for patients with unripe cervix, as randomised controlled studies are lacking. Intravenous oxytocin and misoprostol are contraindicated in these women because of the high risk of uterine rupture. In women with ripe cervix (Bishop Score > 6), intravenous administration of oxytocin is an effective procedure with comparable rates of uterine rupture to those with spontaneous onset of labour. Vaginal prostaglandin E ₂ (PGE ₂ ) and mechanical methods (balloon catheters, hygroscopic cervical dilators) are effective methods to induce labour in pregnant women with unripe cervix and previous Caesarean section. According to current guidelines, the administration of PGE ₂ is associated with a higher rate of uterine rupture compared to balloon catheters. Balloon catheters are therefore a suitable alternative to PGE ₂ to induce labour after previous Caesarean section, even though this is an off-label use. In addition to two meta-analyses published in 2016, 12 mostly retrospective cohort/observational studies with low to moderate levels of evidence have been published on mechanical methods of cervical ripening after previous Caesarean section. But because of the significant heterogeneity of the studies, substantial differences in study design, and insufficient numbers of pregnant women included in the studies, it is not possible to make any evidence-based recommendations based on these studies. According to a recent meta-analysis, the average rate using balloon catheters is approximately 53% and the average rate after spontaneous onset of labour is 72%. The uterine rupture rate was 0.2–0.9% for vaginal PGE ₂ and 0.56–0.94% for balloon catheters and is therefore comparable to the uterine rupture rate associated with spontaneous onset of labour. According to the product informations, hygroscopic cervical dilators (Dilapan-S) are currently the only method which is not contraindicated for cervical ripening/induction of labour in women with previous Caesarean section, although data are insufficient. Well-designed, randomised, controlled studies with sufficient case numbers comparing balloon catheters and hygroscopic cervical dilators with mechanical methods and vaginal prostaglandin E ₂ /oral misoprostol are therefore necessary to allow proper decision-making.

Mifepristone versus balloon catheter for labor induction: a cohort study

OBJECTIVE

to compare trans-cervical balloon catheter with oral administration of mifepristone for induction of labor.

METHODS

Retrospective cohort study including a total of 325 patients; labor was induced with Foley catheter (group I, n = 220) or mifepristone (group II, n = 105). We selected patients with cervical ripening ≤5 cm according to Bishop score (n = 208) and divided into 2 subgroups depending on the parity: group I, primiparous with a Bishop score of ≤5, n = 70 - I (1, ≤5); group I, multiparous with a Bishop score of ≤5, n = 44 - I (2,≤5); group II, primiparous with a Bishop score of ≤5, n = 65 - II (1, ≤5); group II, multiparous with a Bishop score of ≤5, n = 29 - II (2, ≤5). Frequencies and percentages were presented using analysis of variance.

RESULTS

Vaginal delivery occurred more frequently in patients induced by mifepristone (76.5%) vs. Foley catheter (74.5%). However, vaginal delivery within 24 h from the onset of induction occurred in the majority of patients in the Foley catheter groups: 39 (55.7%) and 28 (63.6%) versus 15 (23.1%) and 6 (20.7%) in groups induced with mifepristone. The frequency of cesarean section in the primiparas induced using a Foley catheter was 14%, with the use of mifepristone 21%. However, all multiparas induced with mifepristone delivered vaginally, in contrast to 30.7% of multiparas with the placement of a Foley catheter which required a cesarean delivery.

CONCLUSION

Comparison of the effectiveness of induction of labor with the use of mifepristone and an intracervical balloon Foley catheter showed that both of these methods are successful, with more deliveries within the first 24 hrs achieved by using Foley catheter. The results of this study support the postulate that the success of an induction is largely dependent on the degree of cervical ripening and parity.

Balloon catheter vs oxytocin alone for induction of labor in women with one previous cesarean section and an unfavorable cervix: a multicenter, retrospective study

PURPOSE

To compare the rate of vaginal birth between double-balloon catheter and oxytocin alone for induction of labor in women with one previous cesarean section and an unfavorable cervix.

MATERIALS AND METHODS

A retrospective and observational study was conducted from 2013 to 2017, at the Saint-Etienne University Hospital where women received induction with a double-balloon catheter for 12 h and at the Grenoble Alpes University Hospital where women received induction with a low-dose oxytocin infusion. Primary outcome was the rate of vaginal birth.

RESULTS

Out of 1920 women eligible for attempting a vaginal birth after one previous cesarean section, 501 had a labor induction. Among women with an unfavorable cervix, 160 received a double-balloon catheter in Saint Etienne and 152 received oxytocin alone in Grenoble. The vaginal birth rate was higher in the double-balloon catheter group (61% versus 47% in the oxytocin group). An induction of labor with oxytocin alone reduced chances of vaginal birth (aOR 0.38 CI-95% [0.22-0.66]) compared to cervical ripening with double-balloon catheter. The perinatal morbidity was similar in the two groups. There was, however, 3.9% uterine rupture in the oxytocin group versus 0.6% in the double-balloon group (p = 0.11).

CONCLUSION

For induction of labor in women with one previous cesarean section and with unfavorable cervix, cervical ripening with a double-balloon catheter increases the rate of vaginal birth without increased risk of uterine rupture.

Outpatient labour induction

The inexorable rise in induction rates over the past two decades, in parallel with increasing medical costs and pressure to reduce length of stay, has led to marked logistic difficulties for health care workers, managers and planners. Maternity services are being overwhelmed by the need to allocate staff and delivery suite space for the scheduling and undertaking of induction processes, rather than focussing care for women in spontaneous labour. Induction of labour according to the majority of current protocols and guidelines necessitates increased length of stay and relatively aggressive use of oxytocin (to reduce the time expended in the labour ward from artificial rupture of membranes (AROM) to establishment of labour). This increased oxytocin usage requires increased use of continuous electronic foetal monitoring, and may also increase epidural usage, further increasing the complexity of labour for the woman and her health care workers. Outpatient care after cervical priming and even outpatient care after AROM may help to ease these pressures and may reduce the medicalisation of the birth experience when induction is indicated, with a potential to reduce oxytocin use and associated interventions. If the period between cervical priming to AROM is managed as outpatient care, then the woman may be able to find better psychological and social support at home, as well as maintain autonomy and get better rest prior to the onset of labour. Inpatient AROM could also be followed by outpatient care until the pregnant person returns to the hospital, either in spontaneous labour, or for initiation of syntocinon after 12-18 h. High-quality research has already demonstrated that outpatient care for cervical ripening is acceptable to mothers and caregivers, has economic benefits and has an acceptable safety profile in appropriately selected low-risk inductions.

Vaginal streptococcus B colonization is not associated with increased infectious morbidity in labor induction

INTRODUCTION

Labor induction rates are increasing and, in Finland today, one of three labors is induced. Group B streptococcus (GBS) is a bacterium found in 10%-30% of pregnant women and it can be transmitted to the neonate during vaginal delivery. Although GBS is rarely harmful in the general population, it is the leading cause of severe neonatal infections such as sepsis, pneumonia, and meningitis. In addition, GBS can cause maternal morbidity. Labor induction in GBS-positive women has not yet been investigated but concerns of infectious morbidity associated with balloon catheters have been raised.

MATERIAL AND METHODS

A historical cohort study of 1959 women undergoing labor induction by balloon catheter in Helsinki University Hospital, Finland, between January 1, 2014 and December 31, 2017. Women with viable singleton term pregnancy in cephalic presentation, unfavorable cervix (Bishop score <6), and intact amniotic membranes were included. GBS was screened by rapid qualitative in vitro test (XPert^® GBS) from vaginal and perineal culture upon admission for labor induction. All women testing positive received prophylactic antibiotics.

RESULTS

Of the women, 469 (23.9%) were GBS-positive. The rate of maternal intrapartum infection was 7.4%, being lower in the GBS-positive group compared with the GBS-negative group (4.7% vs 8.3%; p = 0.01). The rate of maternal postpartum infection was 3.9%, and the rate of neonatal infection was 3.3%, both being similar between the groups. Also, no difference in the rates of other adverse neonatal outcomes was seen. No GBS sepses occurred in the study. In multivariable logistic regression, rupture of membranes to delivery interval ≥12 hours was associated with maternal intrapartum and postpartum infection, as well as neonatal infection. Other risk factors for maternal intrapartum infection were GBS-negativity, nulliparity, prolonged pregnancy (≥41 weeks), and Bishop score <3 at the start of induction. Cesarean section was associated with postpartum endometritis, while nulliparity, gestational diabetes, and maternal intrapartum infection were associated with neonatal infection.

CONCLUSIONS

Regarding maternal and neonatal infectious morbidity, labor induction with balloon catheter appears safe in women colonized with GBS when prophylactic antibiotics are administered at the onset of labor or at membrane rupture.

Sonographic cervical length predicts vaginal delivery after previous cesarean section in women with low Bishop score induced with a double-balloon catheter

OBJECTIVE

To assess the role of cervical length when predicting vaginal delivery after a previous cesarean section (CS) in women with low Bishop score following the use of a double-balloon catheter for induction of labor (IOL).

METHODS

A prospective, longitudinal study was conducted at a large teaching hospital in Santiago to recruit pregnant women at term with a previous CS and Bishop score ≤6 for IOL with a double-balloon catheter. The device was maintained for up to 24 h and the patient continued IOL with oxytocin only if the Bishop score was >6. Demographic and clinical variables were recorded and compared against vaginal delivery as the primary outcome. Multivariate logistic regression analysis was used to compare perinatal demographic and clinical variables in women achieving vaginal delivery versus those having a repeat CS.

RESULTS

The final cohort included 40 pregnant women. Women achieving vaginal delivery (n = 17, 42.5%) had statistically significant differences in mean cervical length (24.8 mm versus 33.4 mm, respectively; p = .006), median Bishop score after removing the double-balloon catheter (11 versus 7, respectively; p = .005), and mean interval between double-balloon catheter placement and vaginal delivery or the decision to perform a CS (17.4 h versus 23.6 h, respectively; p = .03). Backward stepwise selection revealed an odds ratio of 0.90 (95% confidence interval = 0.82-0.98) for cervical length and a receiver operating characteristic curve area of 0.73.

CONCLUSION

Cervical length, as determined by transvaginal sonography, proved to be effective in predicting vaginal delivery in women with a previous CS and low Bishop score following the use of a double-balloon catheter for IOL.

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.

Induction of labour at 41 weeks versus expectant management and induction of labour at 42 weeks (SWEdish Post-term Induction Study, SWEPIS): multicentre, open label, randomised, superiority trial

OBJECTIVE

To evaluate if induction of labour at 41 weeks improves perinatal and maternal outcomes in women with a low risk pregnancy compared with expectant management and induction of labour at 42 weeks.

DESIGN

Multicentre, open label, randomised controlled superiority trial.

SETTING

14 hospitals in Sweden, 2016-18.

PARTICIPANTS

2760 women with a low risk uncomplicated singleton pregnancy randomised (1:1) by the Swedish Pregnancy Register. 1381 women were assigned to the induction group and 1379 were assigned to the expectant management group.

INTERVENTIONS

Induction of labour at 41 weeks and expectant management and induction of labour at 42 weeks.

MAIN OUTCOME MEASURES

The primary outcome was a composite perinatal outcome including one or more of stillbirth, neonatal mortality, Apgar score less than 7 at five minutes, pH less than 7.00 or metabolic acidosis (pH <7.05 and base deficit >12 mmol/L) in the umbilical artery, hypoxic ischaemic encephalopathy, intracranial haemorrhage, convulsions, meconium aspiration syndrome, mechanical ventilation within 72 hours, or obstetric brachial plexus injury. Primary analysis was by intention to treat.

RESULTS

The study was stopped early owing to a significantly higher rate of perinatal mortality in the expectant management group. The composite primary perinatal outcome did not differ between the groups: 2.4% (33/1381) in the induction group and 2.2% (31/1379) in the expectant management group (relative risk 1.06, 95% confidence interval 0.65 to 1.73; P=0.90). No perinatal deaths occurred in the induction group but six (five stillbirths and one early neonatal death) occurred in the expectant management group (P=0.03). The proportion of caesarean delivery, instrumental vaginal delivery, or any major maternal morbidity did not differ between the groups.

CONCLUSIONS

This study comparing induction of labour at 41 weeks with expectant management and induction at 42 weeks does not show any significant difference in the primary composite adverse perinatal outcome. However, a reduction of the secondary outcome perinatal mortality is observed without increasing adverse maternal outcomes. Although these results should be interpreted cautiously, induction of labour ought to be offered to women no later than at 41 weeks and could be one (of few) interventions that reduces the rate of stillbirths.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN26113652.

Recent advances in the induction of labor

The rate of labor induction is steadily increasing and, in industrialized countries, approximately one out of four pregnant women has their labor induced. Induction of labor should be considered when the benefits of prompt vaginal delivery outweigh the maternal and/or fetal risks of waiting for the spontaneous onset of labor. However, this procedure is not free of risks, which include an increase in operative vaginal or caesarean delivery and excessive uterine activity with risk of fetal heart rate abnormalities. A search for "Induction of Labor" retrieves more than 18,000 citations from 1844 to the present day. The aim of this review is to summarize the controversies concerning the indications, the methods, and the tools for evaluating the success of the procedure, with an emphasis on the scientific evidence behind each.

[Induction of labor in women with previous caesarean delivery with balloon catheter: Is it worth it?]

OBJECTIF

Balloon catheters for labor induction at term after previous cesarean section is an alternative option to iterative cesarean section. The aim of this study was to analyze the maternal and neonatal outcomes of the trial of labor after cesarean (TOLAC) in women with unfavorable cervix and balloon catheter induction, 2 years after introduction of this process.

METHODS

Unicentric observational study of women with term cephalic singleton, unfavorable cervix (simplified Bishop score<5) after TOLAC using double-balloon catheter. Were analyzed the mode of delivery and severe maternal (uterine rupture, post-partum hemorrhage, severe perineal tears) and neonatal (neonatal unit admission, APGAR<7 at 5minutes, pH<7.1) outcomes. Predictive factors for failed TOLAC were analyzed by using multivariate logistic regression.

RESULTS

Between 2016-2017, 455 (75.4%) women had TOLAC, whose 59 (13%) women with balloon catheter. The overall vaginal delivery (VD) was 73.9%. After Balloon catheter, the VD rate was 50.8%, versus 79.1% after spontaneous labor, and 68.2% after alone oxytocin/artificial membrane rupture induction (P<0.05). Previous VD (aOR 0.176 CI-95% [0.048-0.651]) and prior sweeping membrane (aOR 0.161 CI-95% [0.034-0.761]) was protective for cesarean section after TOLAC. Severe maternal and neonatal morbidities were observed in 10 (17%) and 8 (13.6%) cases, respectively.

CONCLUSION

Double-Balloon catheter is an option for unfavorable cervix and term induction after previous cesarean section. However, the TOLAC in women whose unfavorable cervix is not without maternal and neonatal risk, especially due to its failure.

Efficiency of the Foley catheter versus the double balloon catheter during the induction of second trimester pregnancy terminations: a randomized controlled trial

PURPOSE

To compare induction-to-delivery intervals of Foley catheters and double balloon catheters in second trimester pregnancy terminations.

METHODS

This randomized parallel study was conducted on women who underwent second trimester terminations between December 2016 and December 2017. Pregnant women in the second trimester with a Bishop score < 6 were included in the study. Participants were randomized into two groups, the first being the Foley catheter group and the second being the double balloon catheter group. The time frames from insertion of catheters to the delivery were recorded in each group. A multiple regression analysis was carried out to examine the contribution of factors to the induction-to-delivery interval. A survival analysis was conducted to compare the Foley method and the double balloon method.

RESULTS

A total of 91 pregnant women were included in the final analysis. The induction-to-delivery interval was shorter in the Foley catheter group than in the double balloon catheter group (38 h 54 min ± 21 h 6 min versus 58 h 17 min ± 25 h 56 min). We also found that women with intrauterine fetal death (IUFD) had a shorter time to delivery compared to women with live fetuses (39 h 12 min ± 18 h 46 min vs 51 h 30 min ± 26 h 42 min, p = 0.04). Women with a history of vaginal delivery also had a shorter induction-to-delivery time compared to women who never delivered vaginally before (38 h 12 min ± 17 h 42 min vs 53 h 54 min ± 27 h 18 min, p = 0.004). In the multiple regression analysis, the most significant contributor to the induction-to-delivery time was the method used for induction of labor and followed by other factors including the viability of the fetus (live/IUFD), history of vaginal delivery and PPROM. The survival analysis showed that the induction-to-delivery interval was significantly shorter in the Foley catheter group than in the double balloon catheter group (HR 2.51, 95% CI 1.57-4.00, p = 0.001).

CONCLUSION

During the termination of second trimester pregnancies time from induction of labor to delivery is shorter with the Foley catheter compared to double balloon catheter.

Labor induction in indicated moderate to late preterm birth

Introduction: The primary objective of this study was to evaluate the success of labor induction for indicated moderate and late preterm birth. As secondary objectives, the mode of delivery was assessed.Material and methods: This is an observational study conducted in a tertiary care unit between 2013 and 2015. All patients who underwent labor induction for indicated preterm birth between 32⁺⁰ and 36⁺⁶ weeks of gestation (as premature rupture of membranes, preeclampsia, intrauterine growth restriction, fetomaternal alloimmunization, or intrahepatic cholestasis) were included. The main outcome was the success of labor induction defined by repeated uterine contractions associated with cervical dilation >3 cm. The secondary outcomes were mode of delivery and neonatal outcomes.Results: Among 824 women who gave birth during the study period, 105 (12.7%) underwent induction of labor for indicated preterm birth. Labor induction was successful in 90.5% of cases (95/105), and 72.4% of the women (76/105) delivered vaginally. The success rate did not differ significantly in cases of moderate (32⁺⁰ to 33⁺⁶ weeks), compared with late (34⁺⁰ to 36⁺⁶ weeks) preterm birth (87.5 versus 90.7%, p = .56). The vaginal delivery rate was significantly lower in moderate compared to late preterm birth (37.5 versus 75.3%, p = .03).Conclusion: The success of labor induction and consecutive vaginal delivery were high in case of moderate and late preterm birth. Labor induction can be considered as an effective option for medical indications.

A case of scarred uterine rupture at 11 weeks of gestation having a uterine scar places induced by in vitro fertilization-embryo transfer

Having a uterine scar places a woman at increased risk of complications, such as Cesarean scar pregnancy (CSP), uterine rupture, placenta previa, and placenta accreta, in subsequent pregnancies. We report a case of uterine rupture at 11 weeks of gestation in a woman with a previous Cesarean section. A 43-year-old woman with a history of abdominal myomectomy and Cesarean section had her pregnancy induced by in vitro fertilization with donor eggs. The exact location of the gestational sac was identified on her first day of hospitalization, and her pregnancy was suspected to be a CSP. The following day, the patient complained of sudden lower abdominal pain. A uterine scar rupture was diagnosed, and an emergency surgery was required. It may be that first-trimester screening could allow the early recognition of patients at risk for these perinatal complications.