According to a recent study by researchers at the University of Oxford and published by PLOS Medicine, the mini pill could lead to a small increase in the risk of breast cancer. However, the researchers point out the overall risk is still very low.
The combined pill is already known to carry a small increased risk of breast cancer in women. However, there has been limited research on the effects of the progestin-only ‘mini pill’.
The researchers found progestin-only contraceptives.= are associated with a 20-30% relative risk of breast cancer, making it similar to the combined pill. However, the overall risks remain low, especially for younger women, and studies have shown that the extra risk is gone 10 years after the woman stops taking it.
“Use of combined oral contraceptives, containing both estrogen and progestagen, has previously been associated with a small increase in breast cancer risk but there is limited data about the effect of progestagen-only hormonal contraceptives,” the authors wrote.
For the study, the researchers analyzed data collected by Clinical Practice Research Datalink on women in the UK under the age of 50 who were diagnosed with breast cancer between 1996 and 2017, as well as over 18,000 women who didn’t have breast cancer.
They found that the “excess risk” of five years of using either the combined or mini pill was estimated at 8 per 100,000 users ages 16 to 20 and 265 per 100,000 users ages 35 to 39.
The study stated, “On average, 44% of women with breast cancer and 39% of matched controls had a hormonal contraceptive prescription, with about half the prescriptions being for progestagen-only preparations,”
However, the researchers added that the breast cancer risks are much lower for younger women and that anyone considering hormonal birth control should also consider the “well-established benefits”, such as hormone regulation and family planning.
The researchers added, “Women who are most likely to be using contraception are under the age of 50, where the risk of breast cancer is even lower. For anyone looking to lower their cancer risk, not smoking, eating a healthy balanced diet, drinking less alcohol and keeping a healthy weight will have the most impact.”