Abstract Context The effects of polycystic ovary syndrome (PCOS) on cardiovascular morbidity and mortality are unclear. Objective This work aims to establish the relative risk of myocardial infarction (MI), stroke, angina, revascularization, and cardiovascular mortality for women with PCOS. Methods Data were extracted from the Clinical Practice Research Datalink Aurum database. Patients with PCOS were matched to controls (1:1) by age, body mass index (BMI) category, and primary care practice. The primary outcome was the time to major adverse cardiovascular event (MACE); a composite end point incorporating MI, stroke, angina, revascularization and cardiovascular mortality. Secondary outcomes were the individual MACE end points. Results Of 219 034 individuals with a diagnosis of PCOS, 174 660 (79.7%) met the eligibility criteria and were matched. Crude rates of the composite end point, MI, stroke, angina, revascularization, and cardiovascular mortality were respectively 82.7, 22.7, 27.4, 32.8, 10.5, and 6.97 per 100 000 patient-years for cases, and 64.3, 15.9, 25.7, 19.8, 7.13, and 7.75 per 100 000 patient-years for controls. In adjusted Cox proportional hazard models (CPHMs), the hazard ratios (HRs) were 1.26 (95% CI, 1.13-1.41), 1.38 (95% CI, 1.11-1.72), 1.60 (95% CI, 1.32-1.94), and 1.50 (95% CI, 1.08-2.07) for the composite outcome, MI, angina, and revascularization, respectively. In a time-dependent CPHM, weight gain (HR 1.01; 1.00-1.01), prior type 2 diabetes mellitus (T2DM) (HR 2.40; 1.76-3.30), and social deprivation (HR 1.53; 1.11-2.11) increased risk of progression to the composite end point. Conclusion The risk of incident MI, angina, and revascularization is increased in young women with PCOS. Weight and T2DM are potentially modifiable risk factors amenable to intervention.