Bilateral Oophorectomy Prevalence Among U.S. Women.

Background: Bilateral oophorectomy has been linked to numerous health outcomes, some of which can have a long latency period. Limited data are available on bilateral oophorectomy prevalence among U.S. women. Methods: The National Health Interview Survey fielded measures of bilateral oophorectomy most recently in 2010 and 2015. We pooled these 2 data years to present bilateral oophorectomy prevalence estimates by age-group, race, ethnicity, geographic region, and hysterectomy status. Results: Our study found bilateral oophorectomy was common among older women. Among women aged 70-79 years, 29% reported a bilateral oophorectomy, compared with <1% for women aged 20-29 years. By geographic region, bilateral oophorectomy prevalence among women 20-84 years was 12.3% in the South, 10.8% in the Midwest, 9.4% in the West, and 8.0% in the Northeast. Small numbers limited our ability to generate age-specific estimates for American Indian and Alaska Native women and subgroups of Asian and Hispanic women. Nearly half of women who had a bilateral oophorectomy reported their procedure occurred more than 20 years ago. Among women aged 20-84 years who reported a hysterectomy, 57% reported they also had both of their ovaries removed. Conclusion: Standard measures of incidence rates for ovarian cancer are not adjusted for oophorectomy status. These findings suggest that ovarian cancer incidence rates may be underestimated among older women. Continued monitoring of bilateral oophorectomy prevalence will be needed to track its potential impact on ovarian cancer incidence and numerous other chronic health outcomes.