The use of all-progestogen contraception has increased considerably in recent years. However, a new study published in the PLOS medicine just revealed that the risk of breast cancer under progestins would be similar to that under estrogen-progestogen contraception. We take stock.
Use of progestogen-only contraception
In recent years, the use of all-progestogen contraception has increased considerably. Intended for breastfeeding women, it is also recommended for women with contraindications to estrogen-progestogen pills (risk of cardiovascular disease or smoking following 35, for example).
To know ! All-progestogen contraception refers to a method of contraception that contains only a progestin.
If estrogen-progestogen contraceptives are known to increase the risk of breast cancer, until now, few studies have analyzed the impact of progestogen-only contraception on this same risk.. In this context, British scientists have looked into the subject through a study recently published in the PLOS medicine.
Hormonal contraception and the risk of breast cancer
As part of this study, the scientists relied on data from nearly 10,000 British women under the age of 50 who developed breast cancer between 1996 and 2017. They found that:
- Women on hormonal contraception have a regarding 20% to 30% increased risk of developing breast cancer.
- This result is valid regardless of the contraceptive formula used (oestroprogestogen or progestogen only) and regardless of the mode of delivery (pill, IUD, implant or injection).
The risk of breast cancer under all-progestogen contraception would therefore be similar to that under estrogen-progestogen contraception.
Knowing that the risks of developing breast cancer increase with age, the scientists also calculated the number of additional cases of breast cancer caused by taking hormonal contraception for 5 years:
- When taken between the ages of 16 and 20, 8 out of 100,000 women develop breast cancer.
- In the case of a catch between 35 and 39 years, it is 265 additional women out of 100,000 who develop breast cancer.
For Gillian Reeves, professor at the University of Oxford and co-author of the study, this increased risk nevertheless remains “very small in terms of absolute risk”. The scientist points out that he must be put into perspective with regard to the benefits provided by hormonal contraception (pregnancy control and fairly significant long-term protection once morest other female cancers with oral contraceptives). Another important element: the increased risk of breast cancer linked to hormonal contraception is transient. Once contraception is stopped, this risk declines in the years that follow.
Déborah L., Doctor of Pharmacy
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