By Diario de Avisos/María P. Bonmatí.| A new study published in PLOS Medicine has found a “mild” association between progestin-based hormonal contraceptive methods and breast cancer. Although knows since 2017 that the combinations have this association, the risks of the methods that only use progestins such as the ‘mini pill’ had not been previously examined.
The research, which was based on 9,498 cases of women with breast cancer in the UK and a control group of more than 18,000, found that this method of contraception “is associated with a slightly increased risk of breast cancer (…) similar in magnitude to that associated with hormonal contraceptives.” combined”.
Progestogen-based hormonal contraceptive methods are especially indicated for lactating women, smokers or people who are at risk of thrombus. This is because They do not use estrogens in their preparationwhich avoids the side effects associated with this hormone, such as thrombotic risk.
In addition, the study examined the risk in various forms of administration, including oral, injectable, hormonal intrauterine device, and the subcutaneous implant. According to Antonia Agustípresident of the Spanish Society of Clinical Pharmacology, the most popular shape of administration is the injectable form due to its convenience.
The results of the investigation establish that 44% of the women diagnosed with breast cancer had used some type of hormonal contraceptive in the three years prior to diagnosis. This percentage was higher than in the control group, where 39% had used this method.
In addition, it reflects that there is a relative increase from 20% to 30% in the risk of breast cancer associated with current or recent use of combined oral contraceptives and in those that only carry progestin. However, the researchers note that this increase is very small compared to the small risk of cancer among young women, the main profile of users of hormonal contraceptives.
According to Gill Reeves, study co-author and professor of statistical epidemiology at Oxford University, between the ages of 16 and 20, there could be eight cases per 100,000 users, which sounds considerably different than saying there’s a 25% increase.
While the results are important, experts urge calm and not suddenly stop taking hormonal birth control because of this. Hormonal contraceptives have many proven benefits, such as the improvement of dysmenorrhea and the protective effect against certain types of cancer, such as endometrial, ovarian and colorectal cancer.