OBJECTIVE: To determine if hypertensive disorders of pregnancy (HDP) increased long-term stroke risk in women in the California Teachers Study (CTS), a prospective cohort study, and if aspirin or statin use modified this risk. METHODS: CTS participants aged ≤60 years at time of enrollment in 1995 were followed prospectively for validated stroke outcomes obtained via linkage with California hospital records through 12/31/2015. We calculated unadjusted and adjusted hazard ratios (HR) and 95% confidence intervals (95%CI) for the primary outcomes of (1) all stroke and (2) stroke before age 60, among those with and without history of HDP. We tested for interactions (p<0.2) and performed stratified analyses to assess risk of the primary outcomes in women with and without self-reported use of aspirin or statins. RESULTS: Of 83,749 women included in the analysis, 4070 (4.9%) had HDP. Women with prior HDP had increased risk of all stroke (adjusted HR 1.3, 95%CI 1.2-1.4) but no increased risk of stroke before age 60 (adjusted HR 1.2, 95%CI 0.9-1.7). There was an interaction (p=0.18) between aspirin use and HDP history on risk of stroke before age 60: non-aspirin users had higher risk (adjusted HR 1.5, 95%CI 1.0-2.1) while aspirin users did not (adjusted HR 0.8, 95%CI 0.4-1.7). This effect was not seen with statins. CONCLUSIONS: Controlling for comorbidities, women with prior HDP had increased long-term stroke risk, which was reduced by aspirin use. Randomized trials may be needed to assess whether long-term aspirin use could benefit selected women with a history of HDP.