Higher Rate Of Uterine Rupture Research Articles

The Feasibility of a Trial of Labor after Two Cesarean Deliveries: Outcomes and Prognostic Factors for Success.

This study aimed to determine whether a trial of labor after two cesarean deliveries (TOLAC2) increases the risk of adverse maternal and neonatal outcomes and identify prognostic factors for TOLAC2 success. A retrospective cohort study was conducted at a single medical center. The study group was comprised of women with a history of TOLAC2. Outcomes were compared with women undergoing trial of labor after one previous cesarean delivery (TOLAC1). The primary outcome was trial of labor after cesarean delivery (TOLAC) success. Secondary outcomes included mode of delivery, uterine rupture, and combined adverse outcome (CAO; uterine rupture, postpartum hemorrhage, 5-minute Apgar score < 7, pH < 7.1). Logistic regression was used for the multivariate analysis to identify prognostic factors for TOLAC2 success. A total of 381 women who underwent TOLAC2 were compared with 3,635 women who underwent TOLAC1. Women attempting TOLAC2 were less likely to achieve vaginal births after cesarean delivery (VBAC; 80.8 and 92.5%; odds ratio [OR]: 0.35; 95% confidence interval [CI]: 0.26-0.47; p < 0.001) and more likely to experience uterine rupture (0.8 vs. 0.2%; OR: 4.1; 95% CI: 1.1-15.9; p = 0.02) but not CAO (4.2 vs. 4.8%; OR: 0.88; 95% CI: 0.5-1.5; p = 0.3). TOLAC2 women with no previous vaginal deliveries had a lower chance of VBAC and a higher risk of uterine rupture compared with TOLAC1 women without a prior vaginal delivery (45.2 vs. 86.3%; OR: 0.13; 95% CI: 0.07-0.25; p < 0.001; 2.3 vs. 0%) and TOLAC2 women with a prior vaginal delivery (45.2 vs. 85.3%; OR: 0.14; 95% CI: 0.1-0.3; p < 0.0001; 2.4 vs. 0.6%; OR: 4.1; 95% CI: 0.4-46.3; p = 0.3). Multivariate analysis revealed that a history of vaginal delivery is an independent predictor of TOLAC2 success. Women attempting TOLAC2 are less likely to achieve VBAC and are at greater risk of uterine rupture compared with those attempting TOLAC1. Despite these risks, the overall success rates remain very high, and the absolute risk of adverse outcomes is still very low. Prior vaginal delivery seems to have a protective effect on TOLAC outcomes. These data should be used to counsel women and assist in decision-making when considering the mode of delivery in women with two previous cesarean sections. · TOLAC2 has a lower chance of success and higher rate of uterine rupture compared with TOLAC1.. · Previous vaginal delivery is an independent predictor of TOLAC2 success.. · Overall TOLAC2 outcomes are associated with high chances of success and low risk of uterine rupture..

Impact of adenomyosis on perinatal outcomes: a large cohort study (JSOG database)

BackgroundA previous study investigated the effect of adenomyosis on perinatal outcomes. Some studies have reported varying effect of adenomyosis on pregnancy outcomes in some patients and dependence on the degree and subtype of uterine lesions. To elucidate the impact of adenomyosis on perinatal outcomes.MethodsThis large-scale cohort study used the perinatal registry database of the Japan Society of Obstetrics and Gynecology. A dataset of 203,745 mothers who gave birth between January 2020 and December 2020 in Japan was included in the study. The participants were divided into two groups based on the presence or absence of adenomyosis. Information regarding the use of fertility treatment, delivery, obstetric complications, maternal treatments, infant, fetal appendages, obstetric history, underlying diseases, infectious diseases, use of drugs, and maternal and infant death were compared between the groups.ResultsIn total, 1,204 participants had a history of adenomyosis and 151,105 did not. The adenomyosis group had higher rates of uterine rupture (0.2% vs. 0.01%, P = 0.02) and placenta accreta (2.0% vs. 0.5%, P < 0.001) than the non-adenomyosis group. A history of adenomyosis (odds ratio: 2.26; 95% confidence interval: 1.43–3.27; P < 0.001), uterine rupture (odds ratio: 3.45; 95% confidence interval: 0.89–19.65; P = 0.02), placental abruption (odds ratio: 2.11; 95% confidence interval: 1.27–3.31; P < 0.01), and fetal growth restriction (odds ratio: 2.66; 95% confidence interval: 2.00–3.48; P < 0.01) were independent risk factors for placenta accreta.ConclusionAdenomyosis in pregnancies is associated with an increased risk of placenta accreta, uterine rupture, placental abruption, and fetal growth restriction.Trial registrationInstitutional Review Board of Tottori University Hospital (IRB no. 21A244).

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.

Maternal and neonatal outcomes in the following delivery after previous preterm caesarean breech birth: a national cohort study

The objective of this retrospective, nationwide Finnish population-based cohort study was to determine whether there is an association between preterm caesarean breech delivery in the first pregnancy and maternal and neonatal morbidity in the subsequent pregnancy and delivery. We identified all singleton preterm breech birth in Finland from 2000 to 2017 (n = 1259) and constructed a data set of the first two deliveries for these women. We compared outcomes of the following pregnancy and delivery among women with a previous preterm caesarean breech section with the outcomes of women with one previous vaginal preterm breech birth. p Value, odds ratio, and adjusted odds ratio were calculated. Neonates of women with a previous caesarean preterm breech delivery had an increased risk for arterial umbilical cord pH below seven (1.2% versus 0%; p value .024) and a higher rate of neonatal intensive care unit admission [22.9% versus 15% adjusted OR 1.57 (1.13–2.18); p value <.001]. The women with a previous caesarean section had a higher rate of uterine rupture (2.3% versus 0%; p value .001). They were also more likely in the subsequent pregnancy to have a planned caesarean section [19.9% versus 4% adjusted OR 8.55 (4.58–15.95), an emergency caesarean section [21.5% versus 9.7% adjusted OR 2.16 (1.28–2.18)], or an instrumental vaginal delivery [9.3% versus 3.8% adjusted OR 2.38 (1.08–5.23)]. IMPACT STATEMENT What is already known on this subject? Vaginal birth after caesarean section is generally known to be associated with a higher risk of maternal and neonatal morbidity. What do the results of this study add? The following birth after previous caesarean preterm breech section is associated with a higher rate of uterine rupture and with a higher rate neonatal admission to the neonatal intensive care unit and more often an arterial umbilical cord pH below seven regardless of the mode of the following delivery, compared to women with a subsequent delivery after a previous vaginal preterm breech birth. What are the implications of these findings for clinical practice and/or further research? Our results must be considered when counselling patients regarding their first preterm breech delivery, as the selected method of delivery also affects the outcomes of subsequent pregnancies and deliveries.

Risk of Uterine Rupture with Vaginal Birth after Cesarean in Twin Gestations.

Background Women with a previous cesarean delivery may attempt a subsequent vaginal birth or repeat cesarean. Vaginal birth after cesarean carries a greater risk of uterine rupture, defined as the disruption of all uterine layers, resulting in maternal-fetal morbidity or mortality. It is unclear how the risk of uterine rupture compares in patients with twin gestations who undergo different delivery methods. Objective The purpose of this systematic review is to determine if there is an increased risk of uterine rupture in patients with twin gestations attempting vaginal birth after cesarean (VBAC) versus planned repeat cesarean delivery (PRCD). Study Design. PubMed, Cochrane Library, and CINAHL were searched systematically. Eligible studies were prospective and retrospective studies that evaluated the incidence of uterine rupture in twin pregnancies that attempted VBAC or PRCD. Data were manually extracted from these studies, and the number of events in each group was used to calculate an odds ratio (OR) and 95% confidence interval (CI). Results 4 retrospective studies were included with a total of 7699 participants, 2305 of whom attempted VBAC and 5394 underwent PRCD. The absolute risk of uterine rupture in the VBAC and PRCD groups was 0.87% and 0.09%, respectively. The rate of uterine rupture was significantly higher in the VBAC group than in the PRCD group (OR: 9.43; CI: 3.54–25.17). Conclusion Although VBAC is associated with higher rates of uterine rupture in twin pregnancies when compared with PRCD, the absolute risk of uterine rupture is low in both groups. Depending on individual risk factors, vaginal birth may be offered as a safe option to women with twin pregnancies and a history of cesarean delivery.

Adverse outcomes in early term versus full-term deliveries among higher-order cesarean births

Objective In an attempt to avoid emergency deliveries of women with multiple prior scars, providers may choose to schedule those repeat cesarean births prior to 39 weeks. Our primary goal was to compare rates of assisted ventilation use between neonates with early term (37°-386 weeks) and full-term (39°–396 weeks) deliveries among women with three or more prior cesarean births. Methods A retrospective cohort study of women with three or more previous cesarean births. The study group consisted of women who delivered at early term (37°–386 weeks). The control group consisted of women who delivered at full term (39°–396 weeks gestation). Women with a history of pre-gestational diabetes, gestational hypertension and chronic hypertension were excluded. Data were extracted from the 2017 United States Natality database. Characteristics were compared between groups for potential confounders. Primary outcome, neonatal assisted ventilation use greater than 6 h, and other secondary outcomes (including immediate assisted ventilation in the neonate and uterine rupture) were compared between groups. Multivariable logistic regression analyses were performed to adjust for potential confounding factors between groups. Results A total of 28,584 women with three or more prior cesarean births were included. There were 12,391 women who delivered at early term, and 16,193 who delivered at full term. Neonates born from women who delivered at early term had an increased risk of assisted ventilation use greater than 6 h compared with neonates who delivered at full term (assisted ventilation greater than 6 h, adjusted odds ratio (aOR) 2.08, 95% confidence interval (CI) [1.59–2.73]). Neonates delivered at early term were also more likely to need immediate ventilation use than were neonates delivered at full term (aOR 1.52, 95% CI [1.33–1.73]). Women who delivered at early term had a higher rate of uterine rupture compared with women who delivered at full term (OR 5.67, 95% CI [2.33–13.79]). Conclusion Higher order cesarean births performed early term had an increased risk of neonatal assisted ventilation use greater than 6 h compared with full-term births. These results argue against delivering women with multiple prior uterine scars before term in an attempt to avoid emergency sections.

Rates of vaginal birth after caesarean section: What chance do obese women have?

For women considering vaginal birth after caesarean section (VBAC), obesity has been associated with a lower rate of vaginal birth and a higher rate of uterine rupture. To enhance antenatal counselling, this study aimed to evaluate the success rates of morbidly obese women undergoing a trial of labour (TOL). A retrospective analysis was performed of women who birthed at our hospital who had previously had one caesarean section. Routinely collected data were reviewed for mode of birth for women who underwent a TOL. A number of maternal and neonatal outcomes were also gathered. The data were analysed according to those women with a body mass index (BMI) equal to or above 40, compared to those women with a BMI below 40. From 2011 to 2018, 2097 women gave birth at our hospital and had a caesarean section for a prior pregnancy. Of these women, 1234 (58.9%) had an elective caesarean section and 863 (41.1%) underwent a TOL. Of the women undertaking a TOL, 73.1% gave birth vaginally. Women with a BMI equal to or greater than 40 were less likely to have a successful VBAC compared to women with a BMI less than 40 (58.9% vs 74.1%, P=0.013). Only 50% of women with a BMI equal to or greater than 40 had a successful VBAC if they had not previously had a vaginal birth. Women with a BMI over 40 had lower rates of successful VBAC. Rates were even lower for those who had not had a prior vaginal birth.

Association of uterine rupture with pregestational diabetes in women undergoing trial of labor after cesarean delivery

Objective: To evaluate the association of pregestational diabetes with uterine rupture during a trial of labor with one prior cesarean delivery.Study design: A retrospective study of women undergoing a trial of labor after cesarean. The study group consisted of women with pregestational diabetes and the control group was women without pregestational diabetes. Primary outcome was a uterine rupture. Data were extracted from the USA. Natality Database from 2012 to 2016. Maternal and neonatal outcomes were analyzed. Multivariable logistic regression analysis was used to estimate risks of uterine rupture and maternal and neonatal outcomes.Results: There were 359,504 women undergoing labor after cesarean, with 3508 women with pregestational diabetes and 355,996 without. The prevalence of uterine rupture among women with pregestational diabetes undergoing labor after cesarean was 0.5%, while among women without pregestational diabetes, it was 0.2% (adjusted odds ratio [OR] 2.03 [95% CI 1.18–3.51]; p = .01). There was an increased risk of unplanned hysterectomy among pregnancies complicated by pregestational diabetes (adjusted OR 3.06 [95% CI 1.41–6.66]).Conclusion: Women undergoing a trial of labor, who have pregestational diabetes had a higher rate of uterine rupture than women without a history of pregestational diabetes.

Fertility after complete uterine rupture

This review will address fertility and pregnancy outcome in women with history of uterine rupture. Increasing rates of primary Cesarean delivery and vaginal birth after one or more Cesarean sections will lead to higher rates of uterine rupture. Recent advances in reproductive medicine, open fetal surgery and gynecological surgery may also play a role in increasing uterine rupture rate. The implementation of the American College of Obstetricians and Gynecologists and Royal College of Obstetricians and Gynecologists guidelines on birth after Cesarean section will decrease the Cesarean section rate but may transiently increase the rate of uterine rupture. The maternal and perinatal risks of multiple Cesarean birth are much higher than those of uterine rupture. Women with prior uterine rupture are fertile. They have higher risk of recurrent uterine rupture. Every obstetrician is bound to face the challenge of uterine rupture or women with prior uterine rupture. Those women should have a favorable maternal and perinatal outcome when managed in a tertiary center.

Remote prognosis after primary cesarean delivery: the association of VBACs and recurrent cesarean deliveries with maternal morbidity.

PurposeTo determine the effects of vaginal birth after cesarean (VBAC) versus repeated cesarean sections (RCS) after a primary cesarean section (CS), on the rate of intraoperative and postpartum maternal morbidity.Patients and methodsThis is a retrospective population-based cohort study. During the study period (1988–2005) there were 200,012 deliveries by 76,985 women at our medical center; 16,365 of them had a primary CS, of which 7429 women delivered a singleton infant after the primary CS, met the inclusion criteria, were included in our study, and were followed for four consecutive deliveries. Patients were divided into three study groups according to the outcome of their consecutive delivery after the primary CS: VBAC (n = 3622), elective CS (n = 1910), or an urgent CS (n = 1897). Survival analysis models were used to investigate the effect of the urgency of CS and the numbers of pregnancy predating the primary CS on peripartum complications.ResultsWomen who failed a trial of labor had a higher rate of uterine rupture than those who had a VBAC. Patients who delivered by CS had a higher rate of endometritis than those giving birth vaginally. The rate of cesarean hysterectomy and transfer to other departments increased significantly at the fourth consecutive surgery (P = 0.02 and P = 0.003, respectively). VBAC was associated with a 55% reduction in the risk of intrapartum complications in comparison to a planned CS (hazard ratio [HR] 0.45; 95% confidence interval [CI]: 0.22–0.89. A greater maternal parity at the time of primary CS was associated with lower intrapartum and postpartum morbidities (HR 0.44; 95% CI: 0.24–0.79; HR 0.54; 95% CI: 0.47–0.62, respectively).Conclusions(1) A successful VBAC is associated with a reduction in the intrapartum complications; and (2) maternal morbidity increases substantially from the fourth consecutive cesarean delivery.

Vaginal birth after cesarean delivery in twin gestations: A large, nationwide sample of deliveries

The purpose of this study was to assess the maternal morbidity associated with attempted vaginal birth after cesarean (VBAC) in twin gestations using a large, nationwide sample of deliveries. Data for this study were obtained from an administrative dataset, the Nationwide Inpatient Sample, a representative sample of discharges from non-Federal hospitals, for the years 1993 to 2002. Patients admitted nonemergently for the delivery of twin gestations who had a history of previous cesarean delivery were selected. Patients that either delivered vaginally or who had discharge codes that indicated labor before cesarean delivery were defined as the trial of labor group, while patients who had a cesarean delivery without discharge codes that indicated labor were defined as the elective cesarean group. Various complications of delivery were analyzed for each group. We identified 4705 women who underwent an elective cesarean delivery and 1850 women who underwent a trial of labor. For women who had a trial of labor, 836 (45.2%) delivered vaginally. The rate of uterine rupture was higher in the trial of labor group than in the elective cesarean group (0.9% vs 0.1%, P < .001), and the rate of wound complications was lower (0.6% vs 1.3%, P < .02). The rates of other complications including hysterectomy, transfusion, major postpartum infection, thromboembolism, uterine dehiscence, and pelvic hematoma were not significantly different between the 2 groups. Our study showed a significantly higher rate of uterine rupture in the trial of labor group that is similar to the rates reported for trial of labor after cesarean in singleton pregnancies.

Induction of labor: Comparison of a cohort with uterine scar from previous cesarean section vs. a cohort with intact uterus

Objective. To compare the risk of uterine rupture between a cohort of women with previous low-transverse cesarean section (CS) and a cohort with intact uterus.Methods. All women with a singleton pregnancy and previous low-transverse CS requiring induction of labor from January 1, 1992 to December 30, 2001 (n = 310) were compared with a cohort of women with intact uterus undergoing induction of labor during the same study period (n = 5420). Protocols of induction using prostaglandin E2 gel and oxytocin infusion were consistent within groups, but differed between the previous CS and the intact uterus group.Results. Uterine rupture occurred in 0.3% in the previous CS group vs. 0.03% in the intact uterus group (p = 0.37). Logistic regression analysis showed no significant difference in rate of uterine rupture between the previous CS vs. intact uterus group (p = 0.16) after controlling for maternal age, parity, gestational age at delivery, Bishop score on admission, use of prostaglandin and oxytocin, and birth weight. Our study had adequate power to detect a 0.38% difference in rate of uterine rupture between the two groups (α = 0.05, β = 0.80).Conclusion. Induction of labor is not associated with significantly higher rates of uterine rupture among women with previous low-transverse CS compared with women with intact uterus provided a consistent protocol with strict intervention criteria is adopted.

Risks of induction of labour in women with a uterine scar from previous low transverse caesarean section

Recent studies have shown that among women with uterine scars from previous caesarean section of any type, induction of labour is associated with increased risk of uterine rupture compared with spontaneous labour. We have assessed the risk of uterine rupture in a cohort of women with a previous low transverse caesarean section in whom induction and management of labour were performed according to a strict protocol. Cohort study. University Hospital. All women with a singleton pregnancy and a previous low transverse caesarean section requiring induction of labour from 1/1/1992 to 12/30/2001 (n = 310) were compared with a control cohort during the same study period constituted of women with a previous low transverse caesarean section in spontaneous labour (n = 1011). Clinical characteristics and rate of uterine rupture of women with previous caesarean section undergoing induction of labour were compared with those of women with previous caesarean section in spontaneous labour. Incidence of uterine rupture. Uterine rupture occurred in 0.3% in the previous caesarean section--induction group versus 0.3% in the previous caesarean section--spontaneous labour group (P = 0.9). Logistic regression analysis showed no significant difference in the rate of uterine rupture between the induction and spontaneous labour group (P = 0.67) after controlling for maternal age, parity, duration of labour, gestational age at delivery and birthweight. Among women with a previous low transverse caesarean section, induction of labour is not associated with significantly higher rates of uterine rupture compared with spontaneous labour, provided a consistent protocol with strict criteria for intervention is adopted.

Risk of uterine rupture in labor induction of patients with prior cesarean section: an inner city hospital experience

Objective This study was undertaken to determine the risk of uterine rupture in patients induced with oxytocin or misoprostol after 1 or more previous cesarean sections. Study design Patients with 1 or more previous cesarean sections who delivered after 28 weeks' gestation between 1996 and 2002 were identified by database. Among 3533 total patients, rates of uterine rupture were compared among 4 groups: oxytocin induction (n = 430), misoprostol induction (n = 142), spontaneous labor (n = 2523), and repeat cesarean section without labor (n = 438). Statistical analysis included χ 2 test, Fisher exact test, unpaired t test, and Mantel-Haenszel test. Results Rate of rupture was increased in all inductions compared with that of the spontaneous labor group. Among patients with 1 prior cesarean, rupture rates with misoprostol and oxytocin induction were 0.8% and 1.1%, respectively. Conclusion Induction of labor with oxytocin or misoprostol is associated with a higher rate of uterine rupture compared with those who deliver after spontaneous labor. After 1 prior cesarean, rupture rate with misoprostol induction is not increased compared with oxytocin induction.

The effect of gestational age on trial of labor after Cesarean section

Objectives: To evaluate the effect of gestational age on the rate of successful vaginal delivery and the rate of uterine rupture in patients undergoing a trial of labor (TOL) after a prior Cesarean delivery.Study design: This was a cohort study including patients with a live singleton fetus undergoing a TOL after a previous low transverse Cesarean delivery between 1988 and 2002. Patients were divided into three groups according to gestational age: 24–36 weeks 6 days, 37–40 weeks 6 days and ≥41 weeks. Obstetric outcomes, including the rates of successful vaginal delivery and symptomatic uterine rupture, were compared between the groups. Multivariate logistic regression analysis was performed to adjust for potential confounding factors.Results: There were 253, 1911 and 329 patients in each group, respectively. In patients with advanced gestational age (≥41 weeks) the rate of uterine rupture was significantly higher (0% vs. 1.0% vs. 2.7%, p=0.006) and the rate of successful vaginal deliveries was significantly lower (83% vs. 76.9% vs. 62.6%, p<0.001). After adjusting for confounding variables, advanced gestational age was associated with a lower rate of successful vaginal delivery (odds ratio 0.68, 95% CI 0.51–0.89), and a higher rate of uterine rupture (odds ratio 2.85, 95% CI 1.27–6.42) when compared to 37–40 weeks 6 days.Conclusion: Advanced gestational age is associated with higher rates of failed TOL and uterine rupture.

Spontaneous Versus Induced Labor After a Previous Cesarean Delivery

In Brief OBJECTIVE To compare maternal and neonatal outcomes in spontaneous versus induced labor after one previous cesarean delivery. METHODS Women with one previous cesarean delivery who had spontaneous labor between January 1992 and January 2000 were compared with those whose labor was induced. RESULTS Three thousand seven hundred forty-six patients had a trial of labor (2943 spontaneous, 803 induced). Those induced had more frequent early postpartum hemorrhage (7.3% versus 5.0%; odds ratio [OR] 1.66; 95% confidence interval [CI] 1.18, 2.32), cesarean delivery (37.5% versus 24.2%; OR 1.84; 95% CI 1.51, 2.25), and neonatal intensive care unit (NICU) admission (13.3% versus 9.4%; OR 1.69; 95% CI 1.25, 2.29). There was a trend toward higher uterine rupture rates in those with induced versus spontaneous labor (0.7% versus 0.3%, P = .128) and for patients undergoing dinoprostone (prostaglandin E2) induction versus other methods (1.1% versus 0.6%, P = .62), although neither difference achieved statistical significance. CONCLUSION Induced labor is associated with an increased rate of early postpartum hemorrhage, cesarean delivery, and neonatal ICU admission. The higher rate of uterine rupture in those who had labor induced was not statistically significant. Induced labor is associated with an increased risk of early postpartum hemorrhage, cesarean delivery, and neonatal admission to intensive care unit, but there is no statistically significant difference in rupture rates.

Outcomes of trial of labor following previous cesarean delivery among women with fetuses weighing >4000 g

Objective: To compare outcomes at term of a trial of labor in women with previous cesarean delivery who delivered neonates weighing >4000 g versus women with those weighing ≤4000 g. Study Design: We reviewed medical records for all women undergoing a trial of labor after prior cesarean delivery during a 12-year period. The current analysis was limited to women at term with one prior cesarean and no other deliveries. The rates of cesarean delivery and symptomatic uterine rupture for women with infants weighing >4000 g were compared to the rates for women with infants weighing ≤4000 g. Logistic regression was used to control for the potential confounding by use of epidural, maternal age, labor induction, labor augmentation, indication for previous cesarean, type of uterine hysterotomy, year of delivery, receiving public assistance, and maternal race. Adjusted odds ratios and 95% confidence intervals were calculated. Results: Of 2749 women, 13% (365) had infants with birth weights >4000 g. Cesarean delivery rate associated with birth weights ≤4000 g was 29% versus 40% for those with birth weights >4000 g (P =.001). With use of logistic regression, we found that birth weight >4000 g was associated with a 1.7-fold increase in risk of cesarean delivery (95% CI, 1.3-2.2). The rate of uterine rupture for women with infants weighing ≤4000 g was 1.0% versus a 1.6% rate for those with infants weighing >4000 g (P =.24). Although the logistic regression analysis revealed a somewhat higher rate of uterine rupture associated with birth weights of >4000 g (adjusted OR, 1.6; 95% CI, 0.7-4.1), this difference was not statistically significant. The rate of uterine rupture was 2.4% for women with infants weighing >4250 g, but this rate did not differ significantly from the rate of uterine rupture associated with birth weights ≤4250 g (P =.1). Conclusion: A trial of labor after previous cesarean delivery may be a reasonable clinical option for pregnant women with suspected birth weights of >4000 g, given that the rate of uterine rupture associated with these weights does not appear to be substantially increased when compared to lower birth weights. However, some caution may apply when considering a trial of labor in women with infants weighing >4250 g. In these women with infants weighing >4000 g, the likelihood of successful vaginal delivery, although lower than for neonates weighing ≤4000 g, is still 60%. (Am J Obstet Gynecol 2001;185: 903-5.)