Childbirth-related hospitalizations are among the most common reasons for hospitalizations in the United States, with approximately 3.7 million births occurring annually.1,2 While the birth of a child is typically a joyous occasion, it is important to recognize that certain individuals, particularly those who are non-Hispanic Black (hereinafter Black), often face significant complications during pregnancy and childbirth, including an increased risk of death. Recent data from the National Center for Health Statistics (NCHS) indicates that the maternal mortality rate for Black birthing individuals nearly doubled between 2018 and 2021, rising from 37.3 deaths per 100,000 live births to 69.9.2 These figures represent rates 2.1 and 2.6 times the risk of maternal mortality, respectively, than those observed among non-Hispanic White (hereinafter White) counterparts.

Numerous studies3, 4, 5, 6 have demonstrated that racial inequities in maternal mortality persist even after accounting for differences in socioeconomic and other risk factors such as education, income, health insurance coverage, neighborhood or hospital-level characteristics, and even preexisting comorbidities. Research3, 4, 5,7, 8, 9, 10, 11 demonstrates that structural racism, rather than race itself as a biological construct, plays a central role in explaining these inequities.

In addition to racial inequities, emerging research has shed light on inequities in pregnancy complications and outcomes among birthing individuals with physical disabilities. Compared to birthing individuals without disabilities, birthing individuals with physical disabilities were more likely to develop gestational diabetes, gestational hypertension, preeclampsia, chorioamnionitis, venous thromboembolism, puerperal endometritis, undergo cesarean deliveries, and experience severe maternal morbidity.12, 13, 14, 15, 16, 17, 18 They are also more likely to deliver infants preterm, small for gestational age, with low Apgar scores, and have infants admitted to a neonatal intensive care unit (NICU).13, 14, 15, 16,18,19 Many of these inequities bear resemblance to those observed among Black birthing individuals. Similar to structural racism, it is likely that structural ableism contributes to these inequities.20

Despite the significance of these issues, there is a notable gap in the literature concerning maternal mortality among Black birthing individuals with physical disabilities. In particular, very little is known about how inequities arising from these two avenues of marginalization may combine or compound to exacerbate the risk of maternal mortality. Investigating the compounded risk can provide insights into the significant vulnerability experienced by Black individuals with physical disabilities during childbirth. People who are Black and have physical disabilities likely face a “double burden” of risk for maternal mortality due to enduring systemic oppression rooted in racism and ableism, resulting in even greater inequities than those associated with Black race and physical disability status alone. Generating new knowledge regarding this potentially compounded risk is crucial for prioritizing preconception and perinatal healthcare prevention and treatment services for Black birthing individuals with physical disabilities.

The main objective of this study was to investigate whether Black birthing individuals and birthing individuals with physical disabilities are each at greater risk for maternal mortality and, if so, whether the full effects of being Black with physical disabilities are compounded on an additive scale. We chose to focus on additive interaction, as recommended by VanderWeele and Knol,21 because it has more direct public health implications and is more relevant for identifying groups that would benefit most from targeted interventions.22 We hypothesized that Black birthing individuals with physical disabilities are associated with a compounded risk at the intersection of these two marginalized identities, which exceed the risks associated with Black race alone or physical disability status alone.