Breast cancer may never be far from the minds of women, particularly those who have experience with the disease. The American Cancer Society says about 310,720 new cases of invasive breast cancer are diagnosed in women in the United States in a given year. The World Health Organization says globally 2.3 million women were diagnosed with breast cancer in 2022, and 670,000 died from the disease.
Naturally, women want to do all they can to reduce their risk of developing breast cancer. While it is not possible for women to eliminate their breast cancer risk, recognition of certain variables that can increase risk can help them make more informed decisions. Such variables include the link between breast cancer and hormonal oral contraceptives. Oral contraceptives are used by women to prevent pregnancy.
According to the National Cancer Institute (NCI), nearly all research on the link between oral contraceptives and cancer risk comes from observational studies. Data from these studies cannot definitively establish that oral contraceptives either cause or prevent cancer. This is because women who take oral contraceptives may differ from those who don’t take them in ways other than their oral contraceptive use. However, the NCI says that studies do provide consistent evidence that the risks of breast and cervical cancers are increased in women who use oral contraceptives, whereas the risks of endometrial, ovarian, and colorectal cancers are reduced. As a result, researchers cannot definitively say if oral contraceptives cause or prevent cancer.
A 2017 cohort study published in the New England Journal of Medicine analyzed the risk of invasive breast cancer in Dutch women who used hormonal contraceptives. The study found that the overall risk of breast cancer from contraceptive use was very low. Relative risk increased with duration of use. Oral contraceptives utilize different hormone combinations and strengths, so results can vary depending on the type of pill being taken.
Once women stop taking birth control pills, their risk for breast cancer begins to decrease, according to both NCI and the Susan G. Komen Foundation. After about five years, the risk of breast cancer among women who have taken an oral contraceptive is similar to the risk among women who have never taken the pill at all.
Low-dose pills also may be linked to an increased breast cancer risk just like older, higher-dose forms of birth control. But Susan G. Komen says that the progestin-only “mini-pill,” norethisterone, doesn’t appear to be linked to breast cancer. So those who are considering birth control pills may want to speak to their doctors about norethisterone if breast cancer risk is a concern. Similarly, use of a hormonal IUD, a vaginal birth control ring, or a birth control patch does not seem to be linked to breast cancer.
Although there is a relatively low risk of breast cancer attributed to use of hormonal birth control, women can conduct their own research so they are in the best position to make informed decisions they can be comfortable with going forward.
