Oophorectomy vs ovarian conservation with hysterectomy: cardiovascular disease, hip fracture, and cancer in the Women's Health Initiative Observational Study.

Background: Elective bilateral salpingo-oophorectomy (BSO) is routinely performed with hysterectomy for benign conditions despite conflicting data on long-term outcomes.

Methods: This is a prospective cohort of 25 448 postmenopausal women aged 50 to 79 years enrolled in the Women's Health Initiative Observational Study who had a history of hysterectomy and BSO (n = 14 254 [56.0%]) or hysterectomy with ovarian conservation (n = 11 194 [44.0%]) and no family history of ovarian cancer. Multivariable Cox proportional hazards regression models were used to examine the effect of BSO on incident cardiovascular disease, hip fracture, cancer, and death.

Results: Current or past use of estrogen and/or progestin was common irrespective of BSO status (78.6% of cohort). In multivariable analyses, BSO was not associated with an increased risk of fatal and nonfatal coronary heart disease (hazard ratio, 1.00 [95% confidence interval, 0.85-1.18]), coronary artery bypass graft/percutaneous transluminal coronary angioplasty (0.95 [0.82-1.10]), stroke (1.04 [0.87-1.24]), total cardiovascular disease (0.99 [0.91-1.09]), hip fracture (0.83 [0.63-1.10]), or death (0.98 [0.87-1.10]). Bilateral salpingo-oophorectomy decreased incident ovarian cancer (0.02% in the BSO group; 0.33% in the ovarian conservation group; number needed to treat, 323) during a mean (SD) follow-up of 7.6 (1.6) years, but there were no significant associations for breast, colorectal, or lung cancer.

Conclusions: In this large prospective cohort study, BSO decreased the risk of ovarian cancer compared with hysterectomy and ovarian conservation, but incident ovarian cancer was rare in both groups. Our findings suggest that BSO may not have an adverse effect on cardiovascular health, hip fracture, cancer, or total mortality compared with hysterectomy and ovarian conservation.