Trial of Labor and Vaginal Delivery Rates in Women with a Prior Cesarean

Demographic, Socioeconomic, Health Systems, and Geographic Factors Associated with Vaginal Birth After Cesarean: An Analysis of 2017 U.S. Birth Certificate Data

OBJECTIVES

In order to better understand the current rates of vaginal birth after cesarean (VBAC) in the United States, 2017 U.S. birth certificate data were used to examine sociodemographic and geographic factors associated with the outcome of a VBAC.

METHODS

The 2017 Natality Limited Geography Dataset and block sequential logistic regression were used to examine sociodemographic and geographic factors associated with subsequent births in 2017 in the United States to women with a history of 1 or 2 cesareans (N = 540,711).

RESULTS

The adjusted odds of VBAC were 6% higher for Black women (1.06; 95% CI: 1.04, 1.08) and 18% higher for American Indian/Alaska Native women (aOR 1.18; 95% CI: 1.10, 1.27) relative to white women. Asian/Pacific Islander women were 9% less likely to have a VBAC (aOR 0.91; 95% CI: 0.88, 0.94) than similar white women with a history of cesarean delivery. Latina women had a 10% less likelihood of a VBAC (aOR 0.90; 95% CI: 0.88, 0.92) when compared with non-Latina women. Women with a high school education (aOR 0.85; 95% CI: 0.83, 0.88) or some college (aOR 0.85; 95% CI: 0.84, 0.87) were less likely to have a VBAC than women educated at a baccalaureate level or higher. Women whose births were paid for by Medicaid had a 5% increased likelihood of VBAC over women with private insurance (aOR 1.05, 95% CI: 1.03, 1.07). Women who self-pay have twice the likelihood of VBAC (aOR 1.99; 95% CI: 1.92, 2.07) compared to women with private insurance. The adjusted odds of VBAC were lowest for women giving birth in Southern states (aOR 0.72; 95% CI: 0.71, 0.74) and highest for women giving birth in the Midwest (aOR 1.19; 95% CI: 1.16, 1.22) relative to women in the Northeastern U.S. Thirteen percent (13%) of women who had a VBAC had a certified nurse-midwife (CNM) birth attendant, which is 44% higher than the national CNM-attended birth rate.

CONCLUSIONS FOR PRACTICE

Significant variation exists in VBAC rates based on a number of sociodemographic and geographic factors, likely reflecting disparities in access to vaginal birth after cesarean and differences in preference regarding mode of birth after cesarean. Further research is recommended to better understand and address these disparities to improve maternity care.

Successful vaginal birth after cesarean in the second delivery is not associated with the stage of labor of the primary unplanned cesarean delivery

BACKGROUND

Candidates for trial of labor after cesarean must be carefully screened to maximize success and minimize morbidity. Demographic and obstetric characteristics affecting success rates must be delineated.

OBJECTIVE

We examined whether the labor stage of the primary delivery in which a woman underwent an unplanned cesarean delivery would affect the likelihood that she could achieve a subsequent vaginal birth.

STUDY DESIGN

Electronic medical records-based study of 676 parturients. Trial of labor rates and outcomes were compared between women whose primary cesarean delivery was performed in the first vs. the second stage of labor.

SETTING

Hadassah Medical Center, Israel POPULATION: Women in their second pregnancies, with singleton fetuses, who underwent unplanned cesarean delivery in their first pregnancy and elected trial of labor in the second delivery. The main outcome measures were maternal and neonatal complications and vaginal birth rates in first vs. second stage of labor groups.

RESULTS

In our population, 76 % of women attempt trial of labor after cesarean. Rates of successful vaginal delivery did not differ significantly between those who underwent primary cesarean in the first vs. second stage of labor: 67.4 % vs. 70.2 %, p = 0.483, respectively. Among women whose primary UCD was in the second stage, only 18.2 % (35/192) required a UCD in the second stage in the subsequent delivery, while 58.9 % (113/192) underwent UCD in the first stage in both deliveries.

CONCLUSION

Labor stage of the primary unplanned cesarean delivery, should not dissuade women from a trial of labor after cesarean in their second delivery.

Prediction of vaginal birth after cesarean deliveries using machine learning

BACKGROUND

Efforts to reduce cesarean delivery rates to 12-15% have been undertaken worldwide. Special focus has been directed towards parturients who undergo a trial of labor after cesarean delivery to reduce the burden of repeated cesarean deliveries. Complication rates are lowest when a vaginal birth is achieved and highest when an unplanned cesarean delivery is performed, which emphasizes the need to assess, in advance, the likelihood of a successful vaginal birth after cesarean delivery. Vaginal birth after cesarean delivery calculators have been developed in different populations; however, some limitations to their implementation into clinical practice have been described. Machine-learning methods enable investigation of large-scale datasets with input combinations that traditional statistical analysis tools have difficulty processing.

OBJECTIVE

The aim of this study was to evaluate the feasibility of using machine-learning methods to predict a successful vaginal birth after cesarean delivery.

STUDY DESIGN

The electronic medical records of singleton, term labors during a 12-year period in a tertiary referral center were analyzed. With the use of gradient boosting, models that incorporated multiple maternal and fetal features were created to predict successful vaginal birth in parturients who undergo a trial of labor after cesarean delivery. One model was created to provide a personalized risk score for vaginal birth after cesarean delivery with the use of features that are available as early as the first antenatal visit; a second model was created that reassesses this score after features are added that are available only in proximity to delivery.

RESULTS

A cohort of 9888 parturients with 1 previous cesarean delivery was identified, of which 75.6% of parturients (n=7473) attempted a trial of labor, with a success rate of 88%. A machine-learning-based model to predict when vaginal delivery would be successful was developed. When features that are available at the first antenatal visit are used, the model showed a receiver operating characteristic curve with area under the curve of 0.745 (95% confidence interval, 0.728-0.762) that increased to 0.793 (95% confidence interval, 0.778-0.808) when features that are available in proximity to the delivery process were added. Additionally, for the later model, a risk stratification tool was built to allocate parturients into low-, medium-, and high-risk groups for failed trial of labor after cesarean delivery. The low- and medium-risk groups (42.4% and 25.6% of parturients, respectively) showed a success rate of 97.3% and 90.9%, respectively. The high-risk group (32.1%) had a vaginal delivery success rate of 73.3%. Application of the model to a cohort of parturients who elected a repeat cesarean delivery (n=2145) demonstrated that 31% of these parturients would have been allocated to the low- and medium-risk groups had a trial of labor been attempted.

CONCLUSION

Trial of labor after cesarean delivery is safe for most parturients. Success rates are high, even in a population with high rates of trial of labor after cesarean delivery. Application of a machine-learning algorithm to assign a personalized risk score for a successful vaginal birth after cesarean delivery may help in decision-making and contribute to a reduction in cesarean delivery rates. Parturient allocation to risk groups may help delivery process management.

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

INTRODUCTION

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

METHODS AND ANALYSIS

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

ETHICS AND DISSEMINATION

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

TRIAL REGISTRATION NUMBER

NCT03471858; Pre-results.

Vaginal birth after caesarean versus elective repeat caesarean delivery after one previous caesarean section: a cost-effectiveness analysis in four European countries

BACKGROUND

The OptiBIRTH study incorporates a multicentre cluster randomised trial in 15 hospital sites across three European countries. The trial was designed to test a complex intervention aimed at improving vaginal birth after caesarean section (VBAC) rates through increasing women's involvement in their care. Prior to developing a robust standardised model to conduct the health economic analysis, an analysis of a hypothetical cohort was performed to estimate the costs and health effects of VBAC compared to elective repeat caesarean delivery (ERCD) for low-risk women in four European countries.

METHODS

A decision-analytic model was developed to estimate the costs and the health effects, measured using Quality Adjusted Life Years (QALYs), of VBAC compared with ERCD. A cost-effectiveness analysis for the period from confirmation of pregnancy to 6 weeks postpartum was performed for short-term consequences and during lifetime for long-term consequences, based on a hypothetical cohort of 100,000 pregnant women in each of four different countries; Belgium, Germany, Ireland and Italy. A societal perspective was adopted. Where possible, transition probabilities, costs and health effects were adapted from national data obtained from the respective countries. Country-specific thresholds were used to determine the cost-effectiveness of VBAC compared to ERCD. Deterministic and probabilistic sensitivity analyses were conducted to examine the uncertainty of model assumptions.

RESULTS

Within a 6-week time horizon, VBAC resulted in a reduction in costs, ranging from €3,334,052 (Germany) to €66,162,379 (Ireland), and gains in QALYs ranging from 6399 (Italy) to 7561 (Germany) per 100,000 women birthing in each country. Compared to ERCD, VBAC is the dominant strategy in all four countries. Applying a lifetime horizon, VBAC is dominant compared to ERCD in all countries except for Germany (probabilistic analysis, ICER: €8609/QALY). In conclusion, compared to ERCD, VBAC remains cost-effective when using a lifetime time.

CONCLUSIONS

In all four countries, VBAC was cost-effective compared to ERCD for low-risk women. This is important for health service managers, economists and policy makers concerned with maximising health benefits within limited and constrained resources.

University women's and men's mindsets surrounding postcesarean birth: Findings and implications for practice and policy

BACKGROUND

Nearly twice as many women report preferring vaginal birth after cesarean (VBAC) than actually undergo it. It is unknown whether the preference pattern would hold in childbearing-aged individuals who had not yet been directly influenced by care experiences. We therefore examined postcesarean birth preferences in nulliparous university women and men to provide additional evidence to help advance related policy and practice.

METHODS

An online study of 558 university women and 164 men who read a hypothetical postcesarean birth scenario was conducted. Students selected the option they would prefer for themselves or a partner in a similar situation; these data were analyzed descriptively and for gender differences. Students' written rationales were analyzed qualitatively.

RESULTS

Of women, 38.2% reported preference for VBAC compared with 47.6% of men (P < .05). Thematic analysis revealed that women and men based their preferences on safety, quality of experience, and other concerns similar to those reported among pregnant women making the decision. Assumptions and misinformation were also noted.

CONCLUSION

Given the current primary cesarean rate of ~20%, the current childbearing generation will be facing cesarean and postcesarean birth decisions in appreciable numbers. The relatively high VBAC preference rate reported by our participants, particularly men, is useful in advocating for expanded access and practice. From a constructivist perspective, evidence of young adults' mindsets and misconceptions surrounding postcesarean birth is valuable for developing effective educational interventions.

Counseling women with a previous cesarean birth: toward a shared decision-making partnership

Pregnant women who had a previous cesarean birth must choose whether to have a repeat cesarean or to attempt a vaginal birth. Many of these women are candidates for a trial of labor. Current practice guidelines recommend that women should be thoroughly counseled during prenatal care about the benefits and harms of both a trial of labor after cesarean (TOLAC) and an elective repeat cesarean delivery and be offered the opportunity to make an informed decision about mode of birth in collaboration with their provider. The purpose of this article is to improve the process of counseling, decision making, and informed consent by increasing health care providers' knowledge about the essential elements of shared decision making. Factors that affect the decisions to be made and concepts that are critical for effective counseling are explored, including clinical considerations, women's perspectives, decision-making models, health literacy and numeracy, communicating risk, and the use of decision aids. Issues related to birth sites for TOLAC are also discussed, including access, safety, refusal of surgery, and clinical management.

A critical review of vaginal birth rates after a primary Caesarean in Queensland hospitals

INTRODUCTION

For women with a lower uterine incision without indication for repeat Caesarean section (CS), vaginal birth for their next pregnancy is a safe option. Although these women should be encouraged to consider vaginal birth after a Caesarean section (VBAC) it is not consistently supported in practice. There is relatively little information on the extent to which maternal preference, birthing decisions and outcomes match best available evidence.

AIM

To describe current VBAC rates for women in Queensland, Australia and compare this to safe, achievable VBAC rates reported in national and international studies.

METHOD

Perinatal data from 2004 to 2011 were reviewed to determine current VBAC rates following a primary CS for women birthing in Queensland. These were compared with VBAC rates reported in the literature.

RESULTS

Queensland has a high overall CS rate and high repeat CS rate compared with the national average. In 2010, Queensland VBAC rates for next birth following primary CS were 14% (range 13-21% public sector, 7-11% private hospitals). This is substantially lower than achievable Australian rates of 24% and international rates.

CONCLUSION

Low VBAC rates reflect low numbers of women commencing labour in a pregnancy subsequent to a primary CS. There is unexplained variation in VBAC rates between maternity facilities. Clinical reviews to support evidence-based practice are warranted.

Interventions for supporting pregnant women's decision-making about mode of birth after a caesarean

BACKGROUND

Pregnant women who have previously had a caesarean birth and who have no contraindication for vaginal birth after caesarean (VBAC) may need to decide whether to choose between a repeat caesarean birth or to commence labour with the intention of achieving a VBAC. Women need information about their options and interventions designed to support decision-making may be helpful. Decision support interventions can be implemented independently, or shared with health professionals during clinical encounters or used in mediated social encounters with others, such as telephone decision coaching services. Decision support interventions can include decision aids, one-on-one counselling, group information or support sessions and decision protocols or algorithms. This review considers any decision support intervention for pregnant women making birth choices after a previous caesarean birth.

OBJECTIVES

To examine the effectiveness of interventions to support decision-making about vaginal birth after a caesarean birth.Secondary objectives are to identify issues related to the acceptability of any interventions to parents and the feasibility of their implementation.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 June 2013), Current Controlled Trials (22 July 2013), the WHO International Clinical Trials Registry Platform Search Portal (ICTRP) (22 July 2013) and reference lists of retrieved articles. We also conducted citation searches of included studies to identify possible concurrent qualitative studies.

SELECTION CRITERIA

All published, unpublished, and ongoing randomised controlled trials (RCTs) and quasi-randomised trials with reported data of any intervention designed to support pregnant women who have previously had a caesarean birth make decisions about their options for birth. Studies using a cluster-randomised design were eligible for inclusion but none were identified. Studies using a cross-over design were not eligible for inclusion. Studies published in abstract form only would have been eligible for inclusion if data were able to be extracted.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the selection criteria and carried out data extraction and quality assessment of studies. Data were checked for accuracy. We contacted authors of included trials for additional information. All included interventions were classified as independent, shared or mediated decision supports. Consensus was obtained for classifications. Verification of the final list of included studies was undertaken by three review authors.

MAIN RESULTS

Three randomised controlled trials involving 2270 women from high-income countries were eligible for inclusion in the review. Outcomes were reported for 1280 infants in one study. The interventions assessed in the trials were designed to be used either independently by women or mediated through the involvement of independent support. No studies looked at shared decision supports, that is, interventions designed to facilitate shared decision-making with health professionals during clinical encounters.We found no difference in planned mode of birth: VBAC (risk ratio (RR) 1.03, 95% confidence interval (CI) 0.97 to 1.10; I² = 0%) or caesarean birth (RR 0.96, 95% CI 0.84 to 1.10; I² = 0%). The proportion of women unsure about preference did not change (RR 0.87, 95% CI 0.62 to 1.20; I² = 0%).There was no difference in adverse outcomes reported between intervention and control groups (one trial, 1275 women/1280 babies): permanent (RR 0.66, 95% CI 0.32 to 1.36); severe (RR 1.02, 95% CI 0.77 to 1.36); unclear (0.66, 95% CI 0.27, 1.61). Overall, 64.8% of those indicating preference for VBAC achieved it, while 97.1% of those planning caesarean birth achieved this mode of birth. We found no difference in the proportion of women achieving congruence between preferred and actual mode of birth (RR 1.02, 95% CI 0.96 to 1.07) (three trials, 1921 women).More women had caesarean births (57.3%), including 535 women where it was unplanned (42.6% all caesarean deliveries and 24.4% all births). We found no difference in actual mode of birth between groups, (average RR 0.97, 95% CI 0.89 to 1.06) (three trials, 2190 women).Decisional conflict about preferred mode of birth was lower (less uncertainty) for women with decisional support (standardised mean difference (SMD) -0.25, 95% CI -0.47 to -0.02; two trials, 787 women; I² = 48%). There was also a significant increase in knowledge among women with decision support compared with those in the control group (SMD 0.74, 95% CI 0.46 to 1.03; two trials, 787 women; I² = 65%). However, there was considerable heterogeneity between the two studies contributing to this outcome ( I² = 65%) and attrition was greater than 15 per cent and the evidence for this outcome is considered to be moderate quality only. There was no difference in satisfaction between women with decision support and those without it (SMD 0.06, 95% CI -0.09 to 0.20; two trials, 797 women; I² = 0%). No study assessed decisional regret or whether women's information needs were met.Qualitative data gathered in interviews with women and health professionals provided information about acceptability of the decision support and its feasibility of implementation. While women liked the decision support there was concern among health professionals about their impact on their time and workload.

AUTHORS' CONCLUSIONS

Evidence is limited to independent and mediated decision supports. Research is needed on shared decision support interventions for women considering mode of birth in a pregnancy after a caesarean birth to use with their care providers.