Prompt treatment of severe maternal hypertension (systolic ≥160 mmHg or diastolic ≥110 mmHg for 15 minutes) is recommended within 60 min. Protocol based treatment reduces severe maternal morbidity (SMM). Non-Hispanic black women are at increased risk of SMM from preeclampsia. The effect of protocol based hypertension treatment on racial disparity is understudied. We examined the impact of protocol based treatment in black women. This is a retrospective cohort study of women with severe maternal hypertension from 2015 to 2018. The primary outcome was acute treatment < 60 min, pre- vs post- 2016 protocol implementation. We compared demographics and SMM, between women treated < vs ≥ 60 min. Race was self-identified. Regression analysis incorporated factors including protocol implementation into a model to predict treatment < 60 min and SMM. Before entry, continuous variables were dichotomized for interpretability based on the value that was most discriminative on its receiver operating characteristic curve. Bootstrapping with 1000 repetitions was used for internal validation of area under the curve prediction model. Of 552 women with sustained severe hypertension, 399 were black. Pre- protocol, 30.3% of black and 40.7% of non-black women were treated < 60 min (p = 0.30). Post-protocol, 57.6% of black and 61.1% of non-black women were treated < 60 min (p = 0.54). Treatment disparity between groups was reduced by 6.9% for black women (p=< 0.01). Women with higher pre-treatment systolic and diastolic blood pressure and those treated post-protocol were more likely be treated < 60 min (Table 1). In the regression, treatment post-protocol was the strongest predictor of treatment < 60 min (aOR 3.38 95% CI 2.16-5.29, Table 2). In a separate analysis, treatment < 60 min predicted reduction of SMM (aOR 0.47, 95% CI 0.24-0.91). Inpatient management protocol reduced racial disparity in treatment times. Time to treatment < 60 min is associated with reduced SMM, protocol driven treatment may potentially reduce morbidity related to severe hypertension in black women.View Large Image Figure ViewerDownload Hi-res image Download (PPT)