Severe maternal morbidity and Black-white differences in Washington State

Objective Rates of severe maternal morbidity (SMM) are significantly higher among Black women and some data suggests further worsening of these rates among hospitals with the highest proportion of Black deliveries. In this study, we sought to examine whether Black women have higher SMM in Washington State and whether this varied by hospital. Methods We conducted a retrospective cohort study using linked birth-hospital discharge data from Washington State. We compared Non-Hispanic Black women with Non-Hispanic white women and excluded observations with missing hospital information. SMM was defined using an already published algorithm. We ranked hospitals into low-, medium- and high Black-serving hospitals by using proportions of deliveries to Black women among all deliveries. Multivariable logistic regression models were used to examine the association of Black women with SMM adjusted for demographics, co-morbidities and clustering within hospital. Results In the cohort of 407,808 women, 4556 (1.12%) had SMM. High Black-serving hospitals had the highest rate of SMM (1.94%) as compared to medium Black-serving hospitals (1.16%) and low Black-serving hospitals (1.06%) (p < .01). Odds of SMM was higher in Black women (OR = 1.58, 95% CI: 1.39-1.78) and remained elevated after adjusting for demographics and the level of Black-serving hospital (aOR= 1.29, 95% CI: 1.11-1.49). Conclusion We found that the risk of SMM was higher among Black women. Hospital level performance and health outcomes stratified by maternal race and ethnicity in hospitals and hospital systems should be addressed to further reduce disparities and optimize outcomes.