Women over 50 who have used birth control pills, even if only for a year, have half the risk of developing endometrial cancer compared to women who never have taken oral contraceptives, according to a recent report in the Obstetrics and Gynecology medical journal.
Even if a woman has been off the pill for more than 20 years, the protective effect still is present, says epidemiologist Susan Jick, of the Boston University Medical Center. “Any use at any time” cuts the odds about in half, she says. (Jick studied women who had used the pill for at least a year.)
Jick and her colleagues studied detailed health records of more than 1,000 Seattle women age 50 to 64. One test group consisted of 142 women with endometrial cancer. A separate group of 1,042 women had no cancer. Of the women who had cancer, 18 percent had taken the pill for at least a year, compared to 25 percent of the women without cancer.
“Obviously, it’s something hormonal, but we don’t know yet why this protective effect occurs,” Jick says.
Previous studies have found that use of the pill reduces a woman’s risk of developing endometrial cancer before menopause, but the disease rarely strikes younger women, Jick says. Because the pill was introduced in the 1960s, older women who have used it are reaching their 50s and 60s, when the pill’s protective effect is most apparent and most important, she says.
