Whether it's the pill, the patch, or a range of other products, millions of women today use hormonal contraceptives; so it's little surprise that a new study shows that those who take them have an increased risk of breast cancer.
The new study "confirms that the increased breast cancer risk. that was initially reported with the use of older, often higher-dose formulations also applies to contemporary formulations" of birth control, David Hunter, a professor of epidemiology and medicine at Oxford University's Nuffield Department of Population Health in the United Kingdom, wrote in an editorial that accompanied the study.
Women who now use or recently used hormone-based contraception face a 20 percent higher risk of breast cancer, although the overall risk for most women is relatively low, a new study of 1.8 million women in Denmark has concluded.
"I don't think anyone's going to say stop taking oral contraceptives".
"The risk increases with increasing duration of use and persists for more than five years, if used for longer than five years", said study author Lina Morch, a senior epidemiologist with the University of Copenhagen in Denmark. However, he noted that the clinical implications of this study "must be placed in the context of the low incidence rates of breast cancer among younger women", pointing out that most of the new breast cancer cases occurring in the study were among women using oral contraceptives over the age of 40.
"The increased risk also with newer progestins in hormonal contraceptives has not been shown consistently before, though progestins in postmenopausal therapy has also been found to increase the risk of breast cancer", she added.
Once women stopped using these forms of birth control, the increased risk of breast cancer disappeared if the women had used hormonal contraception for less than five years. After all, it means that almost a quarter of American women are doing something that might increase their risk of developing breast cancer by a third-in theory. Exclusion criteria included women with venous thromboembolism, history of cancer excluding nonmelanoma skin cancer, and a history of infertility treatment. "Taking a very low absolute risk and increasing it only slightly is still a relatively low risk".
However, the overall absolute increase for breast cancer cases was relatively small, marked by an increased of around one new breast cancer case per 7,690 current and recent users of hormonal contraception (13 per 100,000 person-years, 95% CI 10-16).
"Estrogen has been the primary focus of breast cancer research in general, and so we know much more about it than we do progesterone", Gaudet said.
Despite the risk, women will continue to use the pharmaceuticals, Morch said. But these earlier studies looked mainly at older types of birth control pills, which had a higher dose of estrogen than today's pills. "The risk of dying when you're pregnant is probably higher".
Such alternatives include a copper IUD, condoms or, if women are done having children, tubal ligation.
The paper did not make any note of whether birth control impacted mortality from breast cancer, Leath noted.
Beyond the fact that they provide an effective means of contraception and may benefit women with menstrual cramping or abnormal menstrual bleeding, "the use of oral contraceptives is associated with substantial reductions in the risks of ovarian, endometrial, and colorectal cancers later in life".