Women with high risks of developing breast and ovarian cancers because of genetic mutations may reduce the risks if they resort to having their ovaries removed by age 35.

In the new study "Impact of Oophorectomy on Cancer Incidence and Mortality in Women With a BRCA1 orBRCA2 Mutation" published in Journal of Clinical Oncology, Feb. 24, researchers have found that women with faulty BRCA genes, which make them more at risk of developing breast and ovarian cancers than other women, can reduce their risks by undergoing a procedure called oophorectomy i.e. the surgical removal of the ovary.

In the study, researchers identified 5,783 women with BRCA1 or BRCA2 mutation using an international registry. Of these, 2,270 had their ovaries removed while 2,123 already had oophorectomy at the start of the study. The rest of the 1,390 subjects had surgery during the study's follow-up period between 1995 and 2001. During this period, 186 of the subjects developed ovarian, fallopian tube or peritoneal cancer.

The researchers found that the BRCA1 and BRCA2 carriers who underwent ovary removal had their risks significantly reduced. "Preventive oophorectomy was associated with an 80% reduction in the risk of ovarian, fallopian tube, or peritoneal cancer in BRCA1 or BRCA2 carriers and a 77% reduction in all-cause mortality," the researchers wrote.

Study researcher Steven Narod, of the University of Toronto in Canada, said that the best time to undergo oophorectomy is by age 35. "We have a strong basis to recommend that women who have a BRCA1 mutation really benefit from having an oophorectomy, and they should have it by age 35," Narod told HealthDay.

Removing the ovaries does not just reduce risks of ovarian cancer. It can reduce risks of breast cancer as well by affecting the body's hormone levels. Narod said that the surgery can boost a woman's chance of survival even if she already has breast cancer.

Health experts, however, noted that there are implications that could prevent women from having their ovaries removed early. For one, it increases risk of bone-thinning osteoporosis and heart disease. It also leads to early menopause.

''Thirty-five isn't necessarily a magic number,'' said Susan Domchek, of the University of Pennsylvania's Basser Research Center for BRCA. ''If you are talking to a woman who hasn't yet finished having her kids, it's a completely reasonable thing to discuss the low risk of ovarian cancer by age 40 in the context of the other decisions that she's making in her life.''