Low-Dose Birth Control May Cut Ovarian Cancer Risk
Association found for pills containing ethinyl estradiol and norgestrel
THURSDAY, March 22 (HealthDay News) -- Among women who take low-dose oral contraceptives containing ethinyl estradiol and norgestrel, researchers have found an 80 percent reduction in the risk of developing ovarian cancer compared to women who have never used hormonal contraception, according to a report in the March issue of Obstetrics & Gynecology.
Galina Lurie, M.D., and colleagues from the University of Hawaii in Honolulu, examined the association between combined oral contraceptive pills and the risk of epithelial ovarian carcinoma in 745 women with ovarian cancer and 943 matched controls.
The risk of ovarian cancer was significantly lower in women who used low-dose contraceptives (0.035 mg ethinyl estradiol or less, less than 0.3 mg norgestrel; odds ratio, 0.19) compared to women who had never used hormonal contraception. There was also a trend towards lower risk in the low-dose group compared to women taking higher potency estrogens and progestins. Among the 205 women who took norethindrone exclusively, those taking 0.5 mg or less had a significantly lower risk of ovarian cancer compared with those taking 10 mg or more.
"Combined oral contraceptive pills were effective at decreasing the risk of epithelial ovarian carcinoma, with the strongest risk reduction associated with low-potency formulations," Lurie and colleagues conclude.