Association Between Racial Segregation of Labor and Delivery Services and Utilization of Trial of Labor and Vaginal...

Trial of labor after cesarean (TOLAC) offers an opportunity to mitigate maternal morbidity disparities, which are associated with cesarean delivery rates as well as with racial segregation in obstetric care. This study sought to assess the association between the proportion of births to Black individuals at a hospital and the likelihood of low-risk patients undergoing TOLAC and achieving vaginal birth after cesarean (VBAC).

This is a retrospective cohort study of 2017-2019 Nationwide Inpatient Sample deliveries with a history of prior cesarean delivery. We categorized hospitals by the proportion of births to Black individuals: high (top 5%), medium (6-25%), or low (reference), urban-rural status, and teaching status. Primary outcomes were TOLAC and VBAC odds. We used propensity score-matching and performed weighted hierarchical logistic regressions adjusting for maternal age, race and ethnicity, ZIP code median household income quartile, obstetric comorbidity index, hospital delivery volume, and bed size.

A total of 1,734,919 deliveries to low-risk individuals with prior cesarean deliveries were included. One-fifth of these patients (19.7%, n=341,165) attempted labor, among whom 81.4% (n=227,775) delivered vaginally. Compared with low Black-serving hospitals, patients at high Black-serving hospitals had higher TOLAC (adjusted odds ratio [aOR] 1.51, 95% CI, 1.36-1.67) and VBAC odds (aOR 1.24, 95% CI, 1.07-1.43). Black (vs White) patients had lower VBAC odds (aOR 0.88, 95% CI, 0.78-0.98). Among urban teaching hospitals, the TOLAC and VBAC probabilities at high Black-serving hospitals were 25% (95% CI, 22-28%) and 75% (95% CI, 72-78%), respectively, compared with 18% (95% CI, 16-19%) and 70% (95% CI, 67-72%), respectively, at low Black-serving hospitals. Black patients at high Black-serving hospitals had a 72% (95% CI, 69-74%) VBAC probability compared with 67% (95% CI, 64-70%) at low Black-serving hospitals.

Low-risk patients with prior cesarean deliveries had higher odds of TOLAC and VBAC at high Black-serving hospitals. Black (vs White) patients remained less likely to deliver vaginally but had higher chances at high Black-serving hospitals compared with low Black-serving hospitals. Future work should investigate institutional factors that may reduce cesarean deliveries and increase TOLAC and VBAC success, given the significant contribution of cesarean delivery to disparities in maternal morbidity.