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Women's Health: Ovary removal linked to mental decline

Pre-menopausal women should consider estrogen supplements to mitigate the risk, researcher says

New research suggests women who had their ovaries removed before menopause are at increased risk for movement problems and a decline in brainpower. But treatment with the female hormone estrogen until age 50 minimizes these risks.

The study involved women who had one or both ovaries removed because of benign conditions such as ovarian cysts or endometriosis, or who had healthy ovaries removed at the time of a hysterectomy (removal of the uterus) in order to prevent ovarian cancer. Removing the ovaries, the body’s source of estrogen, reduces the risk of cancer, but is known to increase the risks for heart disease and osteoporosis.

Dr. Walter Rocca, a study author and researcher in the department of epidemiology at the Mayo Clinic in Rochester, Minn., says the results will prompt a re-assessment of the risk and benefits of ovary removal.

The study involved more than 2,300 women who had one or both ovaries removed between 1950 and 1987, and a similar number of women with intact ovaries. Compared with women who had intact ovaries, those who’d had their ovaries removed before menopause had a 68 per cent greater risk of developing Parkinsonism (tremor and difficulty with movement) and a 46 per cent greater risk of developing memory problems, dementia or other forms of cognitive impairment. “The younger the woman at the time of surgery, the worse the risk,” Rocca says.

However, treatment with estrogen until age 50 (the approximate age of natural menopause) appeared to eliminate the increased risk of Parkinsonism and cognitive impairment.

Rocca says women need to carefully consider the risks and benefits of ovary removal. Women with a strong family history of ovarian cancer, or genes that increase the risk for this cancer, may decide it is worth the risk. “If you decide you need to do it, then you have to consider (estrogen) treatment so that at least you counteract the negative effect.”