Uterine rupture in patients with a prior cesarean delivery: the impact of cervical ripening

The purpose of this study was to examine factors that were associated with uterine rupture in patients attempting vaginal birth after cesarean delivery. We analyzed the results of all patients attempting vaginal birth after cesarean delivery between September 1996 to December 1999 at a single institution using a contemporaneously maintained registry. Maternal factors, fetal factors, and management of labor were all assessed to determine the risk factors associated with symptomatic uterine rupture at the time of attempted vaginal birth after cesarean delivery. Twenty-eight symptomatic ruptures were identified in 972 attempts of vaginal birth after cesarean delivery at a gestational age greater than 24 weeks (2.88%). The use of preinduction cervical ripening was significantly associated with an increased risk of symptomatic uterine rupture (odds ratio, 3.92; 95% confidence interval, 1.78 to 8.62). Patients who underwent preinduction cervical ripening were significantly less likely to delivery vaginally than women who had not (46.71 versus 76.87%; p < 0.001). No other differences were noted between the two groups. Preinduction cervical ripening is associated with an increased risk of uterine rupture in women attempting vaginal birth after cesarean delivery.     

Transcervical Foley catheter with and without oxytocin for cervical ripening: a randomized controlled trial

OBJECTIVE: To estimate whether adding oxytocin to transcervical Foley catheter preinduction cervical ripening improves induction success. METHODS: This trial enrolled 200 women with singleton pregnancies presenting for preinduction ripening. Patients were randomly assigned to receive either Foley catheter alone (control) or Foley catheter plus low-dose oxytocin (treatment). Providers were not blinded to use of oxytocin, and labor was managed according to routine obstetric protocols. This study was powered to detect a 20% difference in the proportion of patients delivered within 24 hours. Secondary outcomes were related to vaginal delivery rate, duration of induction, complications, and pain management. RESULTS: Results were available for 183 (92 treatment, 91 control) of 200 patients randomly assigned. There were no differences in proportions of deliveries-overall (65% compared with 60%; relative risk [RR] 1.08, 95% confidence interval [CI] 0.86-1.35, number needed to treat 21) or vaginal (48% compared with 46%; RR 1.04, 95% CI 0.76-1.41, number needed to treat 60)-in 24 hours, or cesarean deliveries or times to deliveries between treatment or control groups. Rates of complications were comparable; however, the treatment group had a higher proportion of regional analgesia requirement during induction than controls (23% compared with 9%, P=.01; RR 2.60, 95% CI 1.21-5.56). CONCLUSION: Addition of oxytocin to transcervical Foley catheter does not shorten the time to delivery and has no effect on the likelihood of delivery within 24 hours or vaginal delivery rate, although there is an increased use of analgesia by these patients during ripening. The use of oxytocin in addition to Foley catheter ripening is not justified. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00468520. LEVEL OF EVIDENCE: I.     

A randomized trial comparing vaginal misoprostol versus Foley catheter with concurrent oxytocin for labor induction in nulliparous women

The objective of this study was to compare the efficacy and safety of intracervical Foley catheter with concurrent use of oxytocin versus vaginal misoprostol for labor induction in nulliparous women. Nulliparous women with Bishop score <6 who presented for labor induction were randomized to either 25 microg vaginal misoprostol every 4 hours followed by oxytocin, if indicated, or intracervical Foley catheter with simultaneous use of oxytocin. Among the 162 patients enrolled, 79 (49%) received misoprostol and 83 (51%) received Foley/oxytocin. We were unable to demonstrate a statistically significant difference between the misoprostol group and Foley/oxytocin group in the incidence of cesarean delivery (35% versus 29%; p = 0.37). The induction-to-delivery time was significantly shorter in the Foley/oxytocin group (18 versus 24 hours; p < 0.01). No differences in intrapartum complications, neonatal outcomes, or maternal morbidity were found. When compared with vaginal misoprostol, intracervical Foley catheter combined with oxytocin has a similar efficacy and safety profile for labor induction in nulliparous women. Foley/oxytocin results in a shorter induction-to-vaginal delivery time compared with misoprostol.     

Geburtseinleitung am Termin

Mechanical methods (balloon catheter, natural or synthetic dilators, amniotomy, sweeping of membranes) are the oldest methods to ripen the cervix or to induce labor. Synthetic prostaglandins have, however, increasingly replaced the use of mechanical methods in industrialized countries while in developing countries these methods are still the most frequently used as they are cheap, reversible, and usually do not require fetal monitoring. The mechanical methods in use today usually employ a Foley catheter. Compared with prostaglandins or oxytocin, Foley catheters are equally safe and effective. Moreover, in women with unfavorable cervix, cervical ripening with a Foley catheter seems to be more effective and associated with a lower operative delivery rate. In particular, in women with a previous cesarean delivery, the use of the intracervical Foley catheter must be considered the method of choice for maturation of the cervix, since it is safe with a uterine rupture rate similar to that associated with spontaneous labor.     

Comparison of labor progression between induced and noninduced multiparous women

OBJECTIVE: The incidence of labor induction is rising rapidly in the United States. Among multiparas, labor is often followed with traditional labor curves derived from noninduced pregnancies. We sought to determine how labor progression of multiparous women who presented in spontaneous labor differed from those who were electively induced with and from those induced without preinduction cervical ripening. METHODS: We analyzed data on all low-risk multiparous women with an elective induction or spontaneous onset of labor between 37(+0) and 40(+6) weeks of gestation from January 2002 to March 2004 at a single institution. The median duration of labor by each centimeter of cervical dilatation and the risk of cesarean delivery were computed for 61 women with preinduction cervical ripening and oxytocin induction, 735 women with oxytocin induction, and 1,885 women with a spontaneous onset of labor. An intracervical Foley catheter was used to ripen the cervix. RESULTS: Those women who experienced electively induced labor without cervical ripening had a shorter active phase of labor than did those admitted in spontaneous labor (99 minutes in induced labor versus 161 minutes in spontaneous labor, P < .001). However, the cesarean delivery rate was elevated in the induction group (3.9% versus 2.3%, P < .05). Women who underwent preinduction cervical ripening also had a shorter active phase than those admitted in spontaneous labor (109 minutes versus 161 minutes, P = .01). CONCLUSION: The pattern of labor progression differs for women with an electively induced labor without cervical ripening compared with those who present with spontaneous onset of labor.     

Induction of labor in women with a uterine scar

Objective: To evaluate the frequency of uterine rupture following induction of labor in women with a previous cesarean section. Misoprostol was compared to other methods of induction.

Methods: A retrospective cohort study of 208 women attempting induction of labor after one previous cesarean section. Delivery data were collected retrospectively and compared. Group 1(2009–2010) was compared with Group 2 (2012–2013). In Group 1, the main method of induction was vaginal PGE₂ (prostaglandin-E₂), amniotomy, oxytocin or a balloon catheter. In Group 2, the dominant method of induction was an oral solution of misoprostol. Main outcome measures: frequency of uterine rupture in the two groups.

Results: Nine cases (4.3%) of uterine rupture occurred. There was no significant difference in the frequency of uterine rupture following the change of method of induction from PGE₂, amniotomy, oxytocin or mechanical dilatation with a balloon catheter to orally administered misoprostol (4.1 versus 4.6%, p?=?0.9). All ruptures occurred in women with no prior vaginal delivery.

Conclusion: The shift to oral misoprostol as the primary method of induction in women with a previous cesarean section did not increase the frequency of uterine rupture in the cohort studied.     

Uterine rupture during induced trial of labor among women with previous cesarean delivery

OBJECTIVE: This study was undertaken to compare the rates of uterine rupture during induced trials of labor after previous cesarean delivery with the rates during a spontaneous trial of labor. STUDY DESIGN: All deliveries between 1992 and 1998 among women with previous cesarean delivery were evaluated. Rates of uterine rupture were determined for spontaneous labor and different methods of induction. RESULTS: Of 2119 trials of labor, 575 (27%) were induced. The overall rate of uterine rupture was 0.71% (15/2119). The uterine rupture rate with induced trial of labor (8/575; 1.4%) was significantly higher than with a spontaneous trial of labor (7/1544; 0.45%; P =.0004). Uterine rupture rates associated with different methods of induction were compared with the rate seen with spontaneous labor and were as follows: prostaglandin E(2) gel, 2.9% (5/172; P =.004); intracervical Foley catheter, 0.76% (1/129; P =.47); and labor induction not requiring cervical ripening, 0.74% (2/274; P =.63). The uterine rupture rate associated with inductions other than with prostaglandin E(2) was 0.74% (3/474; P =.38). The relative risk of uterine rupture with prostaglandin E(2) use versus spontaneous trial of labor was 6.41 (95% confidence interval, 2. 06-19.98). CONCLUSION: Induction of labor was associated with an increased risk of uterine rupture among women with a previous cesarean delivery, and this association was highest when prostaglandin E(2) gel was used.     

Effect of prior vaginal delivery or prior vaginal birth after cesarean delivery on obstetric outcomes in women undergoing trial of labor

OBJECTIVE: We sought to study the effects of prior vaginal delivery or prior vaginal birth after cesarean delivery (VBAC) on the success of a trial of labor after a cesarean delivery. METHODS: An observational study of patients who underwent a trial of labor after a single low-transverse cesarean delivery. Patients with a previous cesarean delivery and no vaginal birth were compared with patients with a single vaginal delivery before or after the previous cesarean delivery. The rates of successful VBAC, uterine rupture, and scar dehiscence were analyzed. Multivariable regression was performed to adjust for confounding variables. RESULTS: Of 2,204 patients, 1,685 (76.4%) had a previous cesarean delivery and no vaginal delivery, 198 (9.0%) had a vaginal delivery before the cesarean delivery, and 321 (14.6%) had a prior VBAC. The rate of successful trial of labor was 70.1%, 81.8%, and 93.1%, respectively (P <.001). A prior VBAC was associated with fewer third- and fourth-degree lacerations (8.5% versus 2.5% versus 3.7%, P <.001) and fewer operative vaginal deliveries (14.7% versus 5.6% versus 1.9%, P <.001) but not with uterine rupture (1.5% versus 0.5% versus 0.3%, P =.12). Patients with a prior VBAC had, in addition, a higher rate of uterine scar dehiscence (21.8%) compared with patients with a previous cesarean delivery and no vaginal delivery (5.3%; P =.001). CONCLUSION: A prior vaginal delivery and, particularly, a prior VBAC are associated with a higher rate of successful trial of labor compared with patients with no prior vaginal delivery. In addition, prior VBAC is associated with an increased rate of uterine scar dehiscence.     

Uterine rupture associated with misoprostol labor induction in women with previous cesarean delivery

OBJECTIVE: To review our experience with uterine rupture in patients undergoing a trial of labor with a history of previous cesarean delivery in which labor was induced with misoprostol. STUDY DESIGN: A retrospective chart review was used to select patients who underwent induction of labor with misoprostol during the period from February 1999 to June 2002. Women with a history of cesarean delivery were retrospectively compared with those without uterine scarring. RESULTS: Uterine rupture occurred in 4 of 41 patients with previous cesarean delivery who had labor induced with misoprostol. The rate of uterine rupture (9.7%) was significantly higher in patients with a previous cesarean delivery (P<0.001). No uterine rupture occurred in 50 patients without uterine scarring. Women with a history of cesarean delivery were more likely to have oxytocin augmentation than those without uterine scarring (41% versus 20%; P=0.037). CONCLUSION: Misoprostol induction of labor increases the risk of uterine rupture in women with a history of cesarean delivery.     

A randomized comparison of transcervical Foley catheter to intravaginal misoprostol for preinduction cervical ripening

OBJECTIVE: To compare the efficacy of intravaginal misoprostol tablets with transcervical Foley catheter for preinduction cervical ripening. METHODS: Pregnant women who presented for induction of labor with unfavorable cervices (Bishop score less than 6) were assigned randomly to intravaginal misoprostol (50 microg tablet every 4 hours for a maximum of six doses) or 30-mL Foley catheter placed transcervically with maintenance of traction. RESULTS: Among 111 women, 53 were allocated to misoprostol and 58 to Foley bulb. Contractile abnormalities were more frequent in the misoprostol group (20.4%) than the Foley group (0%) (P <.001). No statistically significant differences were noted between groups in change in Bishop score, preinduction cervical ripening times, and total induction times. There were no statistically significant differences in mode of delivery or adverse neonatal outcomes. Uterine rupture occurred in one woman with two previous cesarean deliveries in the misoprostol group. CONCLUSION: Intravaginal misoprostol and transcervical Foley catheter are equivalent for cervical ripening. Uterine contractile abnormalities and meconium passage are more common with misoprostol.     

Extra-amniotic Foley catheter and prostaglandin E(2) gel for cervical ripening at term gestation.

OBJECTIVE: This study evaluated the efficacy of intravaginal prostaglandin E(2) gel in comparison with that of a Foley catheter for cervical ripening and induction of labor. STUDY DESIGN: Consecutive patients with unfavorable cervix requiring preinduction cervical ripening and induction of labor at term gestation were asked to participate in the study. One hundred and two patients were assigned to treatment with intravaginal prostaglandin E(2) gel (group 1) and 122 patients underwent the placement of an intracervical Foley catheter (group 2). After a maximum of three applications of intravaginal prostaglandin E(2) gel (18h) or after 18h from Foley catheter insertion oxytocin was administered to patients not in active labor. Labor profiles and pregnancy and neonatal outcome were compared between groups. RESULTS: The groups were comparable in term of demographic characteristics, indications for induction of labor, Bishop score at admission. The induction to labor time and the induction to delivery time were similar between groups. The cesarean sections rate was higher in group 1 than in group 2 (26.5 versus 14.7%, P<0.05). This remained significant when the analysis was restricted to nulliparous patients (32.3 versus 14.2%). The incidence of urinary tract infections, chorioamnionitis, and febrile morbidity was similar between groups. CONCLUSION: For preinduction cervical ripening, the Foley catheter is a valid alternative to the application of intravaginal prostaglandin E(2) gel and it is associated with a lower cesarean rate in nulliparous women.     

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

Objectives Ripening of the cervix with a Foley catheter commonly results in cervical dilatation without contractions. We examined the outcome of labour in women who underwent induction of labour using a Foley catheter, followed by either 1. early amniotomy, or 2. augmentation of labour by oxytocin and late amniotomy
Design Prospective randomised clinical trial
Setting Labour and delivery ward of a university teaching hospital
Participants Pregnant women ≥38 weeks of a singleton gestation, who had had no prior caesarean section
Methods All women underwent cervical ripening using a Foley catheter. Following removal of the catheter, women were randomly assigned to either early (   n = 80  ) or late amniotomy (   n = 88  ).
Main outcome measures Comparison of mode of delivery and duration of labour between the two groups
Results The rate of caesarean section was significantly higher in the early amniotomy group compared with the late amniotomy group (25% vs 7.9%; relative risk 1.74; 95% CI 1.3 – 2.34). The increase in caesarean section rate was due primarily to dystocia (15% vs 3.3%; relative risk 1.8; 95% CI 1.32 – 2.45). When excluding caesarean deliveries, no significant difference was found in duration of labour between the groups (8.3 hours (3.8) vs 7.7 hours (2.9))
Conclusions In women who undergo cervical ripening with a Foley catheter, augmentation of labour by oxytocin followed by amniotomy during active labour results in a lower rate of caesarean delivery for dystocia     

Vaginal birth after cesarean section: risk of uterine rupture with labor induction

We assessed the rate of uterine rupture in patients undergoing labor induction for attempted vaginal birth after cesarean (VBAC). A retrospective study was performed of data from a computerized database. Deliveries from January 1, 1998, to June 30, 2001, in the Southern California Kaiser Permanente system were reviewed and various perinatal characteristics analyzed. A total of 16,218 patients had a prior low transverse cesarean section. Of these, 6832 (42.1%) had a trial of labor. Successful VBAC occurred in 86% of patients with spontaneous onset of labor and 66% of patients with labor induction ( p < 0.001). The uterine rupture rate was not different between patients with spontaneous or induced labor (1.0% versus 1.2%, p = 0.51). Similarly, there was no significant difference between oxytocin or prostaglandin E2 induction (1.4% versus 1.0%, p = 0.59). In our study, labor induction did not appear to increase the risk of uterine rupture in women attempting VBAC.     

Transcervical Foley catheter with and without extraamniotic saline infusion for labor induction: a randomized controlled trial

OBJECTIVE: To compare the efficacy of transcervical Foley catheter alone (Foley) to transcervical Foley catheter with extraamniotic saline infusion for labor induction and cervical ripening in women with an unfavorable cervix. METHODS: This was a multicenter, randomized, controlled trial of women presenting for labor induction with a singleton, cephalic fetus, intact membranes, and unfavorable cervix (Bishop score 6 or less). Eligible women were randomly assigned to receive either Foley catheter alone or Foley catheter with extraamniotic saline infusion. All women received concurrent oxytocin administration. The primary study outcome was the induction-to-delivery interval. Secondary outcomes included cesarean delivery, maternal infectious outcomes, and immediate neonatal outcomes. Analysis was by intent to treat. RESULTS: One hundred eighty-eight women met eligibility criteria and were randomly assigned (Foley plus extraamniotic saline infusion, n=97; Foley, n=91). Baseline demographic characteristics, including parity, gestational age, and Bishop score were similar between the study groups. The median induction-to-delivery interval in the extraamniotic saline infusion arm (12.6 hours, interquartile range 9.3-18.8 hours) was similar to that in the Foley arm (13.4 hours, interquartile range 9.6-17.5 hours) (P=. 70). The proportion of women delivered by 24 hours was comparable between groups (delivery 24 hours, extraamniotic saline infusion 89.7%, Foley 87.9%, P=.70), as was the rate of cesarean delivery (Foley 18.7%, extraamniotic saline infusion 27.8%, P=.14). No significant differences were noted between the study groups with respect to rate of chorioamnionitis, endometritis, or immediate birth outcomes. CONCLUSION: In women with an unfavorable cervix, the addition of extraamniotic saline infusion to a transcervical Foley catheter does not improve efficacy for labor induction. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00442663 LEVEL OF EVIDENCE: I.     

Rate of uterine rupture during a trial of labor in women with one or two prior cesarean deliveries.

OBJECTIVE: We sought to determine whether there is a difference in the rate of symptomatic uterine rupture after a trial of labor in women who have had 1 versus 2 prior cesarean deliveries. STUDY DESIGN: The medical records of all women with a history of either 1 or 2 prior cesarean deliveries who elected to undergo a trial of labor during a 12-year period (July 1984-June 1996) at the Brigham and Women's Hospital were reviewed. Rates of uterine rupture were compared for these 2 groups. Potential confounding variables were controlled by using logistic regression analyses. RESULTS: Women with 1 prior cesarean delivery (n = 3757) had a rate of uterine rupture of 0.8%, whereas women with 2 prior cesarean deliveries (n = 134) had a rate of uterine rupture of 3.7% (P =.001). In a logistic regression analysis that was controlled for maternal age, use of epidural analgesia, oxytocin induction, oxytocin augmentation, the use of prostaglandin E(2) gel, birth weight, gestational age, type of prior hysterotomy, year of trial of labor, and prior vaginal delivery, the odds ratio for uterine rupture in those patients with 2 prior cesarean deliveries was 4.8 (95% confidence interval, 1.8-13. 2) CONCLUSIONS: Women with a history of 2 prior cesarean deliveries have an almost 5-fold greater risk of uterine rupture than those with only 1 prior cesarean delivery.     

Uterine rupture and dehiscence associated with intravaginal misoprostol cervical ripening

OBJECTIVE: To evaluate if the prostaglandin E1 analogue misoprostol, when used as an agent for cervical ripening, is associated with uterine rupture. STUDY DESIGN: We performed a two-year retrospective chart review to determine the incidence of uterine rupture in patients with a previous cesarean delivery undergoing cervical ripening or the induction of labor. RESULTS: Uterine dehiscence occurred in 1 and uterine rupture occurred in 3 of 48 women with a prior cesarean delivery treated with 50 micrograms doses of intravaginal misoprostol for cervical ripening. Uterine rupture was found in 1 of 89 women who had an oxytocin infusion for induction of labor and none of the 24 patients who received intravaginal prostaglandin E2 placed for cervical ripening. CONCLUSION: Intravaginal misoprostol appears to be associated with an increased incidence of uterine rupture when used in patients undergoing a trial of labor after cesarean.     

Simplified and standardized intrapartum management can yield high rates of successful VBAC in spontaneous labor

Objective: To examine the outcomes of vaginal birth after cesarean (VBAC) in women, in spontaneous labor, delivering after 37 weeks’ gestation at an institution where trial of labor after a previous cesarean delivery (TOLAC) is encouraged and management of labor is standardized.

Methods: This retrospective cohort study included 3071 women with one previous cesarean only and no vaginal delivery who underwent a trial of labor from 2001 to 2011. Women were managed using the standardized “active management of labor” intrapartum protocol. Outcomes and characteristics of women who delivered vaginally were compared with those who required cesarean delivery.

Results: In spontaneous labor in their second pregnancy, those who attempted TOLAC had a 72.5% (1611/2222) rate of successful VBAC. Women who had a successful VBAC had smaller babies (3584?±?452?g versus 3799?±?489?g; p?p?p?Conclusion: This study shows that serious complications associated with TOLAC are rare providing intrapartum care and decision-making is made simple for the benefit of staff and patients alike. This is achieved through a standardized labor management protocol.     

Uterine rupture during induced or augmented labor in gravid women with one prior cesarean delivery.

OBJECTIVE: Our purpose was to examine the risk of uterine rupture during induction or augmentation of labor in gravid women with 1 prior cesarean delivery. STUDY DESIGN: The medical records of all gravid women with history of cesarean delivery who attempted a trial of labor during a 12-year period at a single center were reviewed. The current analysis was limited to women at term with 1 prior cesarean delivery and no other deliveries. The rate of uterine rupture in gravid women within that group undergoing induction was compared with that in spontaneously laboring women. The association of oxytocin induction, oxytocin augmentation, and use of prostaglandin E(2) gel with uterine rupture was determined. Logistic regression analysis was used to examine these associations, with control for confounding factors. RESULTS: Of 2774 women in the analysis, 2214 had spontaneous onset of labor and 560 women had labor induced with oxytocin or prostaglandin E(2) gel. The overall rate of rupture among all patients with induction of labor was 2.3%, in comparison with 0.7% among women with spontaneous labor (P =.001). Among 1072 patients receiving oxytocin augmentation, the rate of uterine rupture was 1.0%, in comparison with 0.4% in nonaugmented, spontaneously laboring patients (P =.1). In a logistic regression model with control for birth weight, use of epidural, duration of labor, maternal age, year of delivery, and years since last birth, induction with oxytocin was associated with a 4.6-fold increased risk of uterine rupture compared with no oxytocin use (95% confidence interval, 1.5-14.1). In that model, augmentation with oxytocin was associated with an odds ratio of 2.3 (95% confidence interval, 0.8-7.0), and use of prostaglandin E(2) gel was associated with an odds ratio of 3.2 (95% confidence interval, 0.9-10.9). These differences were not statistically significant. CONCLUSION: Induction of labor with oxytocin is associated with an increased rate of uterine rupture in gravid women with 1 prior uterine scar in comparison with the rate in spontaneously laboring women. Although the rate of uterine rupture was not statistically increased during oxytocin augmentation, use of oxytocin in such cases should proceed with caution.     

Preparation for Induction of Labour of the Unfavourable Cervix with Foley Catheter Compared with Vaginal Prostaglandin

Ripening of the unfavourable cervix prior to induction of labour using traction on a Foley catheter (32 patients) was compared with 40 mg of prostaglandin F2 alpha in Tylose gel applied to the external cervical os and held in place for 12 hours with a vaginal diaphragm (25 patients). Each patient in the above groups had a modified Bishop score of 0-3 and was randomly allocated to one or other group. Comparison was made with a further 25 patients in whom the cervical score was 4-6. Timing of amniotomy and commencement of Syntocinon infusion were equivalent for all patients. Prostaglandins conferred no advantage over Foley catheter in terms of amniotomy-delivery interval, operative delivery rate, and condition of the baby one minute after birth. The disadvantages of prostaglandins for cervical ripening are a longer preparation-delivery interval, and cost ($77 versus $4.75 for the Foley catheter). Currently, prostaglandins are not officially approved for use in Australia for induction of labour. It is suggested, therefore, that the Foley catheter is preferable for ripening the unfavourable cervix as a prelude to amniotomy.