Does the contraceptive pill promote breast cancer? Science answers!

Verified on 03/11/2023 by Alexane Flament, Editor
La pilule contraceptive favorise le cancer du sein ? La science répond !

According to British researchers, hormonal contraception may increase the risk of breast cancer. Find out more!

While the links between the combined contraceptive pill and the risk of developing breast cancer are not new, a recent study has brought new evidence to light.

Published in the journal PLOS Medicine on March 21, 2023, the research confirms that all forms of hormonal contraception (pill, IUD, implant, injection) present the same level of risk, being 20 to 30% higher than those choosing another contraceptive method (copper IUD, condom).

Hormonal contraception and increased risk of breast cancer

To reach these conclusions, British and Australian researchers analyzed data from nearly 10,000 women under 50 who had developed breast cancer between 1996 and 2017, as well as a control group of 1,8171 participants.

The result ? Among the half of women affected by the disease, 44% had started taking hormonal contraception, on average 3 years before their diagnosis.

Half of all prescriptions were for progestin-only pills, a contraceptive method that has been on the rise in recent years, and is recommended for breastfeeding women and those with contraindications to estrogen-progestin pills, such as smoking over 35 or risk of cardiovascular disease.

An increase in the risk of breast cancer, but this needs to be qualified

While an increase in the risk of breast cancer was indeed observed, the authors of the study put this into perspective.

In fact, they point out that this « very small increase in absolute risk » must be set against « the benefits derived from hormonal contraception », particularly with regard to other cancers.

« Oral contraceptives provide fairly significant long-term protection against other cancers in women, such as endometrial ovarian cancer, » Gillian Reeves, a professor at Oxford University and co-author of the study, told a press conference, admitting that this argument may be difficult for some women to accept.

The scientist also adds that the increased risk of breast cancer associated with hormonal contraception is transient, diminishing in the years following discontinuation.