Background
Cesarean delivery can be life-saving when medically necessary, but it also carries short- and long-term risks. For people who have had a prior cesarean birth, one important option is trial of labor after cesarean, often called TOLAC. When TOLAC is successful, the result is vaginal birth after cesarean, or VBAC.
VBAC can help reduce the chance of complications associated with repeat cesarean delivery, including surgical injury, infection, hemorrhage, placenta accreta spectrum in future pregnancies, and longer recovery. However, access to TOLAC and VBAC is not equal across all hospitals or patient groups. Prior research has shown that hospital characteristics, staffing patterns, local practice culture, and racial segregation in obstetric care can all influence whether people are offered labor after cesarean.
This study examined whether the racial composition of a hospital’s birthing population, specifically the proportion of births to Black patients, was associated with the likelihood that low-risk patients with a prior cesarean would attempt labor and ultimately deliver vaginally.
Study Purpose
The investigators wanted to know whether hospitals that serve a higher proportion of Black patients differ from hospitals that serve fewer Black patients in two key ways:
1. Whether low-risk patients with a prior cesarean attempt labor rather than having an elective repeat cesarean.
2. Whether those who attempt labor successfully achieve VBAC.
The broader goal was to explore whether segregation in maternity care may help explain differences in cesarean use and maternal outcomes.
Methods
This was a retrospective cohort study using the 2017 to 2019 Nationwide Inpatient Sample, a large U.S. hospital discharge database.
The study included deliveries among patients with a history of prior cesarean delivery who were considered low risk. Hospitals were grouped based on the proportion of births to Black individuals:
– High Black-serving hospitals: top 5%
– Medium Black-serving hospitals: 6% to 25%
– Low Black-serving hospitals: reference group
Hospitals were also categorized by urban-rural location and teaching status.
The main outcomes were:
– TOLAC: whether labor was attempted after a previous cesarean
– VBAC: whether vaginal birth was achieved after attempting labor
To reduce bias from differences in patient and hospital characteristics, the researchers used propensity score matching and weighted hierarchical logistic regression. The analysis adjusted for maternal age, race and ethnicity, neighborhood income level, obstetric comorbidity burden, hospital delivery volume, and hospital bed size.
Key Results
A total of 1,734,919 deliveries to low-risk patients with prior cesarean delivery were included in the analysis.
Overall, about one in five patients, 19.7% (341,165 patients), attempted labor after cesarean. Among those who attempted labor, 81.4% (227,775 patients) delivered vaginally.
Compared with low Black-serving hospitals, patients delivering at high Black-serving hospitals had:
– Higher odds of attempting labor after cesarean: adjusted odds ratio 1.51, 95% CI 1.36 to 1.67
– Higher odds of VBAC: adjusted odds ratio 1.24, 95% CI 1.07 to 1.43
The study also found racial differences within the patient population:
– Black patients had lower odds of VBAC than White patients overall: adjusted odds ratio 0.88, 95% CI 0.78 to 0.98
When the researchers looked specifically at urban teaching hospitals, they found clinically meaningful differences in predicted probabilities:
– At high Black-serving hospitals, the probability of TOLAC was 25% and the probability of VBAC was 75%
– At low Black-serving hospitals, the probability of TOLAC was 18% and the probability of VBAC was 70%
Among Black patients specifically, VBAC probability was:
– 72% at high Black-serving hospitals
– 67% at low Black-serving hospitals
These differences suggest that hospital environment and institutional practice patterns may influence access to labor after cesarean and success with VBAC.
Interpretation
The findings suggest that low-risk patients with a prior cesarean are more likely to be offered or undergo TOLAC at hospitals that serve a larger proportion of Black patients. They are also more likely to achieve VBAC in those settings.
This does not mean that higher Black-serving hospitals are necessarily better in every respect, but it does indicate that institutional factors such as labor management practices, provider attitudes toward TOLAC, staffing, and local obstetric culture may affect whether patients are supported in trying for vaginal birth.
The persistent lower VBAC odds among Black patients overall are important. Even though outcomes improved in high Black-serving hospitals, the racial gap did not disappear. This suggests that structural inequities remain present within the system and that both hospital-level and patient-level factors may contribute.
Why This Matters
Cesarean delivery is a major contributor to maternal morbidity, and the burden of maternal complications is not evenly distributed. Black women and birthing people experience higher rates of severe maternal morbidity and mortality in the United States. Because repeated cesareans can increase future pregnancy risks, improving equitable access to TOLAC and VBAC may be one way to reduce harm.
This study highlights an important public health issue: the organization of maternity services can affect clinical decisions and outcomes. If hospitals that serve more Black patients are more likely to support labor after cesarean, understanding what they do differently could help reduce disparities elsewhere.
Possible contributing factors may include:
– Differences in willingness to offer TOLAC
– Variation in hospital policies regarding VBAC eligibility
– Availability of continuous labor support and anesthesia services
– Provider experience and comfort with labor after cesarean
– Institutional norms around avoiding repeat surgery when safe to do so
Clinical Implications
For patients with a prior cesarean and no contraindication to vaginal birth, TOLAC remains an important option to discuss with obstetric clinicians. Counseling should include the benefits and risks of both repeat cesarean and labor after cesarean, including the possibility of uterine rupture, the chance of successful VBAC, and the implications for future pregnancies.
For hospitals and health systems, the findings suggest a need to examine barriers to TOLAC and VBAC, especially in low Black-serving hospitals. Potential steps include:
– Reviewing institutional VBAC policies
– Standardizing counseling and candidacy assessment
– Ensuring appropriate staffing for labor management
– Addressing implicit bias and structural racism in obstetric care
– Monitoring cesarean rates and VBAC outcomes by race and hospital type
Limitations
As with all studies using administrative data, there are limitations. The database may not capture all clinical details needed to determine precise medical eligibility for TOLAC, such as the exact type of prior uterine incision or nuanced labor indications. There may also be unmeasured factors such as patient preference, provider recommendation, or insurance-related barriers.
Because this was an observational study, it can show association but not prove that serving more Black patients causes higher TOLAC or VBAC rates. Still, the size of the dataset and the consistency of the findings make the results important and clinically relevant.
Conclusion
Among low-risk patients with a prior cesarean delivery, hospitals that serve a higher proportion of Black patients had higher rates of trial of labor after cesarean and higher VBAC success. Black patients overall were still less likely than White patients to deliver vaginally, but their chances were better at high Black-serving hospitals than at low Black-serving hospitals.
These findings suggest that hospital-level practices and structural features of maternity care may play a meaningful role in shaping cesarean use and racial disparities in maternal outcomes. Future research should identify the institutional factors that support safer, more equitable access to TOLAC and VBAC, with the goal of reducing unnecessary repeat cesareans and improving maternal health.