The Effect of a Multicomponent Prenatal Intervention on Maternal Satisfaction Following Vaginal Birth After Cesarean: A Randomized Controlled Trial

Counseling patients who are considering a trial of labor after cesarean (TOLAC) is a challenging task given the risks and benefits of either approach. While calculators exist to give patients an idea of their likelihood of having a successful vaginal birth after cesarean (VBAC), their validity is limited by outdated mathematical methods used to develop them. Most importantly, current VBAC calculators only offer insight into the chance of successful VBAC, without any ability to predict the risk of adverse outcomes relevant to both the patient and neonate. The objective of this study is to develop a prediction model for individualized risks and benefits of a TOLAC using modern mathematical techniques.This was a secondary analysis of the Cesarean Registry database, the same database used in developing the Maternal-Fetal Medicine Units (MFMU) VBAC calculator. The primary outcome was the prediction of the success of VBAC. Secondary outcomes were the prediction of uterine rupture, maternal complications, and neonatal complications. Inclusion criteria were term, singleton gestation, and cephalic presentation pregnancies with one prior low transverse cesarean delivery (CD). Exclusion criteria included intrauterine fetal demise, planned cesarean, and prior myomectomy. Univariate comparisons identified variables that were independently associated with VBAC. An optimal decision tree was used to create a prediction model. A test set was withheld for validation. A risk calculator tool was developed for the prediction of successful VBAC and adverse perinatal outcomes. Adverse maternal outcomes: uterine dehiscence, hysterectomy, postpartum hemorrhage, endometritis, intensive care unit admission, thromboembolic event, readmission, and organ injury. Adverse neonatal outcomes: hypoxic-ischemic encephalopathy, respiratory distress, seizures, apnea, respirator use, death, and cord blood pH < 7.1.The study population included 73,262 deliveries of which 12,942 patients met inclusion and exclusion criteria. After removing cases for the test set, the included patients were 8,078 patients, of which 5,970 people had a successful VBAC (73.9%). Parity, number of years since prior CD, prepregnancy body mass index (BMI), delivery BMI, maternal age, and previous VBAC were associated with successful VBAC. A risk predictor calculator was created, and a receiver operator characteristic curve was developed with an area under the curve of 0.72. The tool was also developed to identify a person's risk of uterine rupture, composite maternal morbidity, and neonatal morbidity.VBAC for patients with term, cephalic, singleton gestation was associated with several variables. This advanced calculator tool will facilitate shared decision-making about the value of a TOLAC regarding the personalized risks of maternal and neonatal morbidity. By using more advanced mathematical models, this tool allows providers to predict not only the likelihood of successful VBAC but also the risk of maternal and neonatal morbidity involved in attempting VBAC. · Current VBAC calculators are limited by the mathematical methods used to make them.. · This novel calculator uses more advanced machine-learning methods than previous calculators.. · This VBAC calculator predicts both the chance of success VBAC and the risk of morbidity.. · The more modern VBAC calculator gives providers more information to use when counseling patients..

INTRODUCTION: Counseling on the likelihood of successful vaginal birth after cesarean (VBAC) is essential, because a failed trial of labor after cesarean (TOLAC) increases perinatal morbidity. Trial of labor after cesarean induction of labor (IOL) has higher rates of failure versus spontaneous TOLAC. We assessed VBAC success for TOLAC IOL and examined the utility of the VBAC calculator in predicting successful TOLAC. METHODS: An IRB-approved, retrospective cohort study of patients (2020–2023) with a history of prior cesarean birth undergoing IOL was conducted. Logistic regression comparing calculator-predicted VBAC success rates to actual VBAC success was performed. RESULTS: Of 270 patients undergoing TOLAC IOL, 138 (51.1%) had successful VBAC versus 172 (63.6%) as predicted by the VBAC calculator (P&lt;.0001). Successful VBAC was associated with history of prior vaginal delivery (VD) (P=.0008), prior VBAC (&lt;0.0001), and no history of arrest disorder (P=.0007). VBAC occurred in 72% of patients with prior VD and 46% without prior VD. Vaginal birth after cesarean occurred in 82% of patients with prior VBAC and 43% without prior VBAC. Of those with successful VBAC, 22% had prior arrest disorder. In failed IOL, 41% had prior arrest disorder. No association was found between successful VBAC and age, body mass index, chronic hypertension, or diabetes. The VBAC calculator was documented as part of TOLAC counseling in only 31 patients (11.39%). CONCLUSIONS/IMPLICATIONS: True VBAC success rate was 51.1%. This is 20% lower than the national rate (74.3%), which does not separate IOL from spontaneous labor. Trial of labor after cesarean patients should be counseled about lower success rates of VBAC post-IOL. The VBAC calculator should be used to provide more accurate counseling in patients undergoing TOLAC IOL.

587: Hospital contribution to variation in rates of vaginal birth after cesarean: A Michigan Value Collaborative study

Evaluation of: Mercer BM, Gilbert S, Landon MB et al., for the National Institute of Child Health and Human Development Maternal-Fetal medicine Units Network: Labor outcomes with increasing number of prior vaginal births after cesarean delivery. Obstet. Gynecol. 111(2), 285-291 (2008). From a prospective US multicenter cohort of 45,988 patients with a singleton gestation and a prior cesarean, 13,532 women that elected to attempt a vaginal birth after cesarean (VBAC) were selected for this secondary analysis. This study was conducted to estimate the success rates and risks of an attempted VBAC according to the number of previously successful VBAC attempts. Outcomes evaluated included VBAC success, maternal major morbidity (e.g., uterine rupture and surgical complications), neonatal morbidity (e.g., intensive care nursery admission and acidemia) and maternal and neonatal death. The VBAC success rate rose incrementally from 63.3 to 91.6% in patients that had from zero to four or more prior successful VBACs. Uterine rupture and peripartum risks decreased by 50% after the initial successful VBAC and did not increase with increasing prior VBAC number. Neonatal morbidity did not increase with increasing VBAC number.

To investigate the incidence and pregnant outcome on vaginal birth after cesarean (VBAC). From January 2005 to December 2015, clinical data of 507 cases with VBAC in West China Second Hospital were studied retrospectively. There were 370 cases of VBAC from January 2013 to December 2015 as study group (VBAC group), in contrast, 740 cases of elective repeat cesarean section (ERCS group) and 740 primiparas of vaginal delivery without history of cesarean section as control groups, the pregnancy outcome were analyzed between the study group and control groups respectively. (1) There were 76 547 total births from January 2005 to December 2015. Among these, 10 178 (13.296%, 10 178/76 547) patients had a single prior low transverse cesarean section, of which 4.981% (507/10 178) had VBAC. The incidence of VBAC was rising from 1.020%-3.704% during 2005-2012 to 6.028%-7.662% during 2013-2015. The rate of scared uterus during 2013-2015 was 18.269% (5 539/30 319), of which 9.26% (513/5 539) chose trial of labor after cesarean section (TOLAC). Successful VBAC occurred in 72.12% (370/513) of patients with TOLAC, and 27.88% (143/513) delivered by emergency cesarean. (2) The following parameters of the successful group and the unsuccessful VBAC group were compared, maternal age (29±4) versus (34±4) years, body mass index at prenatal visit (22.2±1.4) versus (22.6±1.4) kg/m(2), gestational age (38.7±0.9) versus (39.6±1.3) weeks, birth weight (3 326±317) versus (3 404±285) g, and the rate of induction of labor 0 (0/370) and 6.29% (9/143), there were significant differences (all P<0.01). There was no statistical difference between two group for lower uterine segment (P=0.947). (3) The duration of labor of VBAC group and 740 primiparas of vaginal delivery without history of cesarean section was compared, (10.3±1.8) versus (11.5±2.0) hours, there was significant difference (P<0.01). There were no statistical difference between two groups for the following parameters, including postpartum hemorrhage, hospitalization duration, the ratio of 5-minute Apgar score≥8, neonatal admission rate (all P>0.05). (4) The postpartum hemorrhage and hospitalization duration in VBAC group incidence were respectively (194±34) ml and (2.32±0.49) days, and the indexes of the ERCS group were respectively (419±57) ml and (4.14±0.78) days, there were significant differences (all P<0.01). There were no statistical difference between two groups for the ratio of 5-minute Apgar score≥8 and neonatal admission rate (all P>0.05). The majority of patients choose ERCS rather than TOLAC. It's important to assess the indications and contraindications of patients for the successful VBAC, and to monitor maternal and fetal conditions during the delivery process. The premise of TOLAC is a comprehensive understanding of closely monitoring the progress of delivery. Compared with the ERCS, VBAC could reduce patients' postpartum hemorrhage and hospitalization duration, improve the outcomes of pregnancy, and the cesarean section rate could be reduced.

To estimate whether excessive weight gain or obesity are risk factors affecting success for vaginal birth after cesarean (VBAC). Patients attempting VBAC were identified by the International Classification of Diseases, 9th Revision, codes "VBAC" and "non-primary C-section" and by reviewing logbooks on labor and delivery. A chart review identified patients attempting VBAC who were eligible for inclusion. Exclusion criteria included multiple gestation, more than one previous cesarean delivery, previous classical uterine scar, delivery at less than 36 weeks of gestation, and incomplete information. Patients were divided into the following categories: underweight (body mass index [BMI] < 19.8), normal weight (BMI 19.8-26), overweight (BMI 26.1-29), and obese (BMI > 29). Excessive weight gain was defined as a weight gain of more than 40 lb. Variables of interest included diabetes, previous successful vaginal delivery or VBAC, and presence of recurrent indication for cesarean delivery. We identified 1,213 patients who met inclusion criteria. Overall, the VBAC success rate was 77.2%. The success rates for BMI less than 19.8, 19.8-26, 26.1-29, and greater than 29 were 83.1%, 79.9%, 69.3%, and 68.2%, respectively, P < .001. Obese patients were almost 50% less likely to have a successful VBAC when compared to underweight patients, odds ratio 0.53, 95% confidence interval 0.29-0.98, P = .043. Similarly, patients who gained more than 40 lb were almost 40% less likely to be successful at VBAC than those who gained less than that amount, odds ratio 0.63, 95% confidence interval 0.42-0.97, P = .034. They had a VBAC success rate of 66.8%, whereas patients who gained less than 40 lb were successful 79.1% of the time, P < .001. Excessive weight gain during pregnancy and obesity both decrease VBAC success. Proper patient selection will help increase the likelihood of successful VBAC.

788: Is induction with early amniotomy associated with a higher likelihood of vaginal birth after cesarean?

Do They Stand a Chance? Vaginal Birth after Cesarean Section in Adolescents Compared to Adult Women

216: Can prediction of vaginal birth after cesarean at admission for delivery be improved?

Background: Little is known about trial of labor after cesarean (TOLAC) uptake and vaginal birth after cesarean (VBAC) success on the national level, which is important as national-level data may help shape future clinical guidelines. This study examined correlates of trial of labor and successful VBAC among women with one prior cesarean in the United States in 2016. Materials and Methods: We used publically available birth certificate data for 2016. Outcomes were TOLAC among women with one prior cesarean (N = 338,311) and VBAC among women with a TOLAC (N = 76,688). We used logistic regression to assess the association between the outcomes and the following categories of independent variables: social determinants of health, demographic and medical factors impacting birth, behavioral factors, and geographic access. Results: About 23% of women had a TOLAC, and 74% of women with a TOLAC gave birth vaginally. Black women had higher odds of TOLAC relative to White women, but lower odds of successful VBAC. Women without a high school degree had higher odds of TOLAC and of successful VBAC compared to women who completed high school or beyond, as did women with inadequate prenatal care utilization. Conclusions: Understanding correlates of TOLAC and successful VBAC at the population level is important for developing national guidelines that can be considered and individualized at the patient/provider level.

Vaginal Birth After Caesarean Section: Review of Antenatal Predictors of Success

To estimate the rate of success and risk of maternal morbidities in women with three or more prior caesareans who attempt vaginal birth after caesarean (VBAC). Retrospective cohort design. Multicentre, from 1996 to 2000, including 17 tertiary and community delivery centres in north-eastern USA. A total of 25 005 women who had had at least one prior caesarean delivery. Women who attempted VBAC with three or more prior caesareans were compared with those who attempted after one and two prior caesareans. Univariable and stratified analyses were used to select factors for multivariable analyses for maternal morbidity. Maternal characteristics were compared using a Student's t test, Mann-Whitney U test, chi-square test or Fisher's exact test, as appropriate. The primary outcome was composite maternal morbidity, defined as at least one of the following: uterine rupture, bladder or bowel injury, or uterine artery laceration. Secondary outcomes were VBAC success, blood transfusion and fever. Of 25 005 women, 860 had three or more prior caesarean deliveries: 89 attempted VBAC and 771 elected for repeat caesarean. Of the 89 who attempted VBAC, there were no cases of composite maternal morbidity. They were also as likely to have a successful VBAC as women with one prior caesarean (79.8% versus 75.5%, adjusted OR 1.4, 95% CI 0.81-2.41, P = 0.22). Women with three or more prior caesareans who attempt VBAC have similar rates of success and risk for maternal morbidity as those with one prior caesarean, and as those delivered by elective repeat caesarean.

Objective Predicting likelihood of vaginal birth after cesarean (VBAC) is a cornerstone in counseling patients considering a trial of labor after cesarean (TOLAC). Yet, the simplified Bishop score (SBS), a score comprised cervical dilation, station, and effacement assessment used to predict successful vaginal delivery, has not been applied to the TOLAC population. We evaluated the relationship between admission SBS and likelihood of successful VBAC. We also determined the predictive characteristics of SBS, compared to cervical dilation alone, for successful VBAC. Methods This is a secondary analysis of a prospective cohort study of patients with a singleton gestation, ≥37 0/7 weeks gestation, and prior cesarean admitted to Labor & Delivery between 2010 and 2014. The primary outcome of successful VBAC was compared between those with a favorable (score >5) and unfavorable (score ≤5) admission SBS. Secondary outcomes were select maternal and neonatal outcomes. Adjusted risk ratios were estimated using multivariable logistic regression analyses. Receiver-operating characteristic curves compared predictive capabilities of cervical dilation alone to SBS for successful VBAC. Results Of the 656 patients who underwent a TOLAC during the study period, 421 (64%) had a successful VBAC. 203 (31%) and 453 (69%) had a favorable and an unfavorable admission SBS, respectively. After adjusting for body mass index and prior vaginal delivery, patients with a favorable admission SBS had a 30% greater likelihood of successful VBAC compared to those with an unfavorable SBS (aRR 1.30, 95% CI 1.16–1.40). Admission cervical dilation alone performed similarly to SBS as a predictor of successful VBAC, with a receiver-operator characteristic curve area under the curve (AUC) of 0.68 (95% CI 0.64–0.72) versus an AUC 0.66 (95% CI 0.62–0.70), respectively (p = .07). There were no differences in adverse maternal or neonatal outcomes between those with an unfavorable and favorable SBS. Conclusions A favorable admission SBS is associated with an increased likelihood of VBAC. Although both admission SBS and cervical dilation alone are only modest predictors of VBAC, admission cervical dilation performs overall similarly to current models for VBAC prediction and is an objective, reproducible, and generalizable measure. Our study highlights the value of waiting until end of pregnancy (rather than the first prenatal visit) to conclude patient counseling on the decision to TOLAC in order to consider admission cervical assessment, particularly cervical dilation.

In Brief Objective To describe attempted and successful vaginal birth after cesarean (VBAC) rates and uterine rupture rates for women with and without prior cesareans, and compare delivery outcomes in hospitals with different attempted VBAC rates. Methods We used California hospital discharge summary data for 1995 to calculate attempted and successful VBAC rates and uterine rupture rates. We used multivariate logistic regression models to evaluate and adjust for age, ethnicity, and payment source. We report the relative risk (RR), attributable fraction, and 95% confidence intervals (CIs) for uterine rupture. Results There were 536,785 delivery discharges during 1995. The cesarean rate was 20.8%, and 12.5% of women had histories of cesareans. Of women with histories of cesareans, 61.4% attempted VBAC and 34.8% were successful. There were 392 uterine ruptures (0.07%). Women with prior cesareans were 16.98 (95% CI 13.51, 21.43) times more likely to experience uterine rupture, attributable fraction 66% (95% CI 60%, 73%). Among women with prior cesareans, those who attempted VBAC were 1.88 (95% CI 1.45, 2.44) times as likely to have uterine rupture, attributable fraction 34% (95% CI 21%, 46%). Women who delivered in hospitals with high attempted VBAC rates were less likely to have cesarean deliveries, more likely to have successful VBACs, and more likely to experience uterine ruptures. Conclusion Uterine rupture occurs at a low rate in women with and without prior cesarean delivery. Risk of rupture is increased among women with prior cesarean delivery and among those who attempt VBAC. California state discharge data confirm a low rate of uterine rupture among women attempting vaginal birth after cesarean.

To validate a previously developed vaginal birth after cesarean (VBAC) prediction model using a patient cohort different than that from which it was derived. We performed a cohort study of all term pregnant women (January 2002-August 2007) with one prior low transverse cesarean delivery attempting a trial of labor. Variables used in the final prediction model (maternal age, prepregnancy body mass index, ethnicity, prior vaginal delivery, prior VBAC, and indication for prior cesarean delivery) were extracted from medical records and used to calculate an individual woman's predicted VBAC success rate. These rates at the level of the study population then were partitioned into deciles and compared with the actual VBAC rates. Of 545 women who fit the inclusion criteria, 502 had complete data available. A total of 262 (52.2%) had VBAC. The predicted probability of VBAC, as calculated by the regression equation, was significantly higher in those who had a successful trial of labor (median 78.4%, interquartile range 62.1-88.2) than in those who did not (median 59.7%, interquartile range 50.8-75.3, P<.001). The predictive model had an area under the receiver operating characteristic of 0.70 (95% confidence interval 0.65-0.74, P<.001), which was similar to that originally described. The actual VBAC rates did not differ from the predicted rates when the predicted chance of success was less than 50%. Above a 50% predicted success, the achieved success rates were consistently 10-20% lower. The published nomogram is predictive of VBAC success. It may help pregnant women contemplating a trial of labor reach a more informed decision. II.