Differences in disease severity and delivery gestational age between black and white patients with hypertensive disorders of pregnancy.

Objectives: We sought to quantify racial differences in disease severity and delivery gestational age among Black and White patients with a diagnosis of a hypertensive disorder of pregnancy.

Study Design: This was a retrospective cohort of all Black and White pregnant patients carrying non-anomalous singleton or twin gestations at a single tertiary healthcare system who were diagnosed with a hypertensive disorder of pregnancy, 2014-2020.

Main Outcome Measure: The primary outcome was delivery < 34 weeks' gestation. Secondary outcomes were delivery < 28 weeks', preeclampsia with severe features, acute renal insufficiency, HELLP syndrome, cesarean delivery, classical cesarean delivery, small for gestational age, severe maternal morbidity, and severe composite neonatal morbidity. Outcomes were compared by race. Data were analyzed using chi square, t-test, and logistic regression.

Results: 3,522 patients (29.8% Black) met inclusion criteria. Black patients had a higher odds of delivery < 34 weeks' [adjusted odds ratio (aOR) 2.22, 95% CI 1.7-2.89] and < 28 weeks' (aOR 2.39, 95% CI 1.43-3.99) and developing preeclampsia with severe features (aOR 1.92, 95% CI 1.62-2.29) than White patients. Black patients also had higher aOR of classical cesarean, severe maternal morbidity, and a small for gestational age neonate.

Conclusions: Black patients are more likely to experience severe hypertensive disorders of pregnancy and preterm delivery compared to White patients. These findings suggest that Black-White disparities in preterm birth may be partially attributable to disparities in onset and severity of hypertensive disorders of pregnancy.