Results:

Over the 20 years of follow-up, 1,438 cases of CHD were identified, and 5,296 women had laparoscopically confirmed endometriosis. These women were older, had earlier age at menarche, were more likely to be nulliparous, had lower parity, were more likely to use oral contraceptives, and more likely to have a family history of MI at ages <60 years, compared with women who had not been diagnosed with endometriosis at baseline. Compared to women without endometriosis, women with endometriosis had a greater risk for CHD (relative risk [RR], 1.62; 95% confidence interval [CI], 13.9-1.89). For each specific CHD condition, the risk was greater for women with endometriosis including for MI (RR, 1.52; 95% CI, 1.17-1.98), for angina (RR, 1.91; 95% CI, 1.59-2.29) confirmed by angiography, and for revascularization (coronary artery bypass grafting or percutaneous coronary intervention) (RR, 1.35; 95% CI, 1.08-1.69) after adjustment for demography factors, family history, and lifestyle and anthropometric characteristics. The risk of CHD appeared to vary by age with the highest risk observed among women 40 years of age or younger (RR, 3.08; 95% CI, 2.02-4.70). As women aged, the CHD risk associated with endometriosis declined. Having had a hysterectomy/oophorectomy was associated with higher risk of combined CHD compared with not having had a hysterectomy/oophorectomy (RR, 1.51; 95% CI, 1.34-1.71).