MONDAY, Aug. 1, 2005 (HealthDay News) -- Removing the ovaries along with the uterus during a hysterectomy done for noncancerous conditions is common in women over the age of 45, but a new study suggests it may not be the wisest course for long-term survival.
Keeping the ovaries is clearly best for women up to age 65 who are at average risk of getting ovarian cancer and get a hysterectomy for noncancerous conditions, said study author Dr. William Parker, a staff gynecologist at Santa Monica-UCLA Medical Center in Los Angeles. His finding appears in the August issue of Obstetrics & Gynecology.
In his review of 20 years of published data from various sources, Parker and his team found that preserving the ovaries in this group of women reduces their risk for heart disease and hip fractures.
"Twenty-five times more women die from heart disease every year than from ovarian cancer," Parker said.
For many years, the prevailing medical wisdom has been to remove the ovaries when the uterus is removed if women are past childbearing age to prevent ovarian cancer, Parker said. About half of women have their ovaries removed during hysterectomy.
However, the ovaries keep making small amounts of estrogen for years after natural menopause. Ovarian testosterone and androstenedione, two hormones, have been documented in some women in their 80s. Muscle and fat cells turn testosterone into circulating estrogen, in turn protecting against heart disease and osteoporosis.
Each year in the United States, more than 600,000 hysterectomies are performed. Ninety percent are performed for benign diseases, Parker said, such as uterine fibroids or endometriosis, in which the lining of the uterus begins to grow on the outside of the uterus and on nearby organs.
Parker's team tried to find out the age-specific risks for five conditions linked to the presence or absence of ovaries, including ovarian cancer, breast cancer, heart disease, hip fractures and stroke. They compared four strategies for hypothetical groups of women aged 40 to 80 who had a hysterectomy: ovary conservation with or without estrogen therapy later, and ovary removal with or without estrogen therapy later.
For women at average risk of ovarian cancer, heart disease, osteoporosis, breast cancer and stroke, the probability of survival to age 80 after hysterectomy at ages 50 to 54 ranged from 62 percent for those who kept their ovaries but didn't take estrogen, to 53 percent for those who had their ovaries removed but didn't take estrogen.
Keeping the ovaries without estrogen therapy reduced the percent of women dying by age 80 of heart disease from 15 percent to 7 percent, and those dying of hip fractures from nearly 5 percent to 3 percent.
The reductions in those two diseases, Parker said, far outweigh the increase in ovarian cancer deaths by age 80.
"If you take out the ovaries, the risk of ovarian cancer goes to zero," Parker said, "but you lose the protection against heart disease and the prevention of osteoporosis."
Was he surprised? "Yes. I really did think that taking out the ovaries wasn't beneficial for [overall] mortality," Parker said. "But I didn't suspect that leaving them in would be so clearly beneficial."
Another expert familiar with the new study, Dr. Richard Paulson, a professor of reproductive medicine at the University of Southern California, Los Angeles, praised the work. "It's wonderful," he said. "When I first read it, my first thought was, why has this not been done before?"
"What has been lacking up to this point was a good analysis for the data. You've got the cancer doctors saying, 'You can't leave them behind, the patient is going to get cancer [of the ovaries] and die.' On the other hand, you have the hormone doctors, the endocrinologists who are saying that the postmenopausal ovaries make important hormones, and we should leave them intact. What was needed was for someone to crunch the numbers and come up with relative risks."
Neither Paulson nor Parker think practice will change overnight. But the new study is food for thought, and women aged 45 and above who are facing a hysterectomy for noncancerous conditions should be aware of the new analysis, they said.
More information
To learn more about hysterectomy, visit the The National Women's Health Information Center.
