WEDNESDAY, April 27, 2011 (HealthDay News) -- Among women who have had a hysterectomy, those whose ovaries were also removed had a lower risk of subsequent ovarian cancer and no greater risks of heart disease, hip fractures or other types of cancer, a new study indicates.
Using data gathered from the Women's Health Initiative (WHI) study, the researchers analyzed more than 25,000 postmenopausal women aged 50 to 79 who underwent hysterectomies but had no family history of ovarian cancer. About 56 percent also had their ovaries removed during the procedure -- the most common non-obstetric major surgery among American women -- and 79 percent had used some form of hormone replacement therapy (HRT).
The results contradicted those of the only other large study of its type, the Nurses' Health Study, which suggested a link between ovary removal and increased risks of heart disease, cancer deaths and overall mortality. However, the NHS had a much longer follow-up period (24 years vs. nearly eight years) and a lower average participant age (51 years old vs. 63 years old).
"What our study emphasizes is that it's very unclear because there's this equivocal mix of data," said study author Dr. Vanessa Jacoby, an assistant professor of gynecology at University of California at San Francisco. "There's really no right answer about what to do about removing or retaining your ovaries during a hysterectomy. Definitely a lot more work needs to be done."
The study is published in the April 25 issue of the Archives of Internal Medicine.
About 600,000 hysterectomies are performed each year in the United States, the vast majority to treat benign gynecologic conditions such as uterine fibroids or abnormal bleeding. Ovary removal is routinely offered to women aged 40 and older to prevent ovarian cancer, the study said, which strikes only 1.4 percent of women but is extremely deadly.
The decision to remove the ovaries in women with no family history of ovarian cancer became more controversial in the wake of the dramatic decline of HRT use among women to alleviate menopausal symptoms. In the WHI trial, HRT was associated with higher risks of cancer, heart disease and strokes.
"Our study was definitely not a study about the use of hormone therapy," Jacoby said.
While some studies have indicated that retaining ovaries after a hysterectomy helps women fight off bone-thinning osteoporosis, the new research suggests that those without ovaries may not suffer additional risks, the study said.
Also, differences in hormone levels between women who keep or lose their ovaries are not sufficient to show a demonstrable effect on health outcomes, Jacoby said. In fact, those retaining their ovaries during hysterectomy report lower rates of subsequent ovarian cancer than women who don't ever have the surgery.
Of the 25,448 women studied, those with ovary removal had a slightly higher prevalence of treated high blood pressure and angina, but didn't report more prior cardiovascular problems such as heart attack, stroke or pulmonary blood clots.
Even among women with no family history of ovarian cancer, some might opt to have their ovaries removed during hysterectomy anyway because of a history of breast cancer, said Dr. Elizabeth Poynor, a gynecologic oncologist and pelvic surgeon at Lenox Hill Hospital in New York City.
"Removing the ovaries potentially decreased the risk of developing breast cancer in elevated-risk women," Poynor said. "They can travel hand-in-hand in some families."
While the majority of the women in this study had used HRT after menopause, seemingly without ill effects, Poynor said that doesn't mean it's safe to use supplemental hormones.
"Hormone replacement therapy and management of ovaries is highly individualized medicine," she said. "But we feel we have a responsibility to our patients to clarify the situation. This is another study that demonstrates to us that our data is not sound enough for us to draw broad, sweeping conclusions."
The U.S. Department of Health and Human Services has more onhysterectomies.