New research in a special edition of Obstetrics & Gynecology on the subject of racism in reproductive health explores patient-led approaches to a Vaginal Birth After Cesarean (VBAC) calculator.

In the United States, the most used VBAC prediction model was the Maternal-Fetal Medicine Units’ VBAC calculator, which estimated the probability of having a VBAC by assessing age, BMI and clinical history, as well as race and ethnicity. The inclusion of race and ethnicity provided Black and Latinx pregnant people with scores that were 5 to 15 percentage points lower than white people. After more than 10 years of use, the MFMU revised the calculator to exclude race and ethnicity in response to criticism that the model obscured structural inequities and perpetuated obstetric racism.

New research from Nicholas Rubashkin and colleagues fills gaps in understanding how pregnant people use a numeric estimate of their VBAC probability, and how patients responded to the VBAC calculator’s use of race and ethnicity as a risk factor.

Through patient interviews and recorded prenatal visits, the researchers found that Black and Latina women who were interested in a VBAC often had to reject the role of race and ethnicity in their calculated scores. Rejecting the role of race and ethnicity could mean challenging as unfair or racist the calculator’s implication that Black and Hispanic pregnant people were less capable of having a vaginal birth. For instance, Marta, who identified as Hispanic and was assessed to have a VBAC probability of 25%, expressed anger that race and ethnicity should factor into her scoring. “That [the inclusion of race] makes me angry. Like why would my race change what my body does, what it’s supposed to do?”

The researchers also found that the numeric probability for a successful VBAC did not factor into decision making for many patients who were interested in having a VBAC.

Although some women attempted VBACs despite being given lower scores, there’s evidence that some providers used the calculator to counsel Black and Latina patients into repeat cesarean deliveries, an approach that must be seen within the history of obstetric racism in the US, which has included subjecting Black, Latinx, and minoritized populations to invasive treatments, forced sterilization, or court-ordered c-sections.

Although removing race and ethnicity has mitigated the calculator’s most concerning effects, some of the patient-led approaches in this study still hold for the new VBAC calculator. These findings show that a numeric probability for VBAC may not be highly valued or important to all patients, especially those who strongly intend to try a vaginal delivery. The researchers suggest that the patient-led approaches described in their paper may be an untapped resource for achieving a more person-centered and equitable approach to counseling around birth options.