Background Racial disparities contribute to maternal morbidity in the United States. Hypertension is associated with poor maternal outcomes, including stroke. Disparities in hypertension might contribute to maternal strokes. Methods and Results Using billing data from the Healthcare Cost and Utilization Project's National Inpatient Sample, we analyzed the effect of race/ethnicity on stroke during delivery admission in women aged 18 to 54 years delivering in US hospitals from January 1, 1998, through December 31, 2014. We categorized hypertension as normotensive, chronic hypertension, or pregnancy-induced hypertension. Adjusted risk ratios (aRRs) and 95% CIs were calculated using log-linear Poisson regression models, testing for interactions between race/ethnicity and hypertensive status. A total of 65 286 425 women were admitted for delivery during the study period, of whom 7764 were diagnosed with a stroke (11.9 per 100 000 deliveries). Hypertension modified the effect of race/ethnicity (P<0.0001 for interaction). Among women with pregnancy-induced hypertension, black and Hispanic women had higher stroke risk compared with non-Hispanic whites (blacks: aRR, 2.07; 95% CI, 1.86-2.30; Hispanics: aRR, 2.19; 95% CI, 1.98-2.43). Among women with chronic hypertension, all minority women had higher stroke risk (blacks: aRR, 1.71; 95% CI, 1.30-2.26; Hispanics: aRR, 1.75; 95% CI, 2.32-5.63; Asian/Pacific Islanders: aRR, 3.62; 95% CI, 2.32-5.63). Among normotensive women, only blacks had increased stroke risk (aRR, 1.17; 95% CI, 1.07-1.28). Conclusions Pregnant US women from minority groups had higher stroke risk during delivery admissions, compared with non-Hispanic whites. The effect of race/ethnicity was larger in women with chronic hypertension or pregnancy-induced hypertension. Targeting blood pressure management in pregnancy may help reduce maternal stroke risk in minority populations.
Keywords: disparities; hypertension; maternal morbidity; preeclampsia; pregnancy; stroke.