Hormonal Contraceptives and Cancer Risk

It's well-established that taking the oestrogen/progesterone combination contraceptive pill, slightly increases the risk of a woman developing breast cancer. No such data has been available, however, about the progesterone-only pill. This knowledge gap may account for the increasing UK popularity of progesterone-only contraception. Indeed, in 2020, roughly equal numbers of women took the combined and the progesterone-only pills. An Oxford University study has now tried to fill the gap in our knowledge (https://www.theguardian.com/society/2023/mar/21/all-hormonal-contraceptives-carry-small-increased-risk-breast-cancer). This Oxford study looked at almost 9,500 women aged between 20 and 49, who developed invasive breast cancer. These subjects were compared to more than 18,000, closely-matched, women, without breast cancer. The study revealed that the progesterone-only pill, also slightly increases a user's chance of developing breast cancer. The investigators opine that, as this risk is small, it should not discourage the use of this pill. Pregnancy, itself, carries substantially greater (albeit different) health risks. This study makes it clear, however, that all hormonal contraceptives carry a small and roughly equal health risk. Progesterone-only is not safer than the oestrogen/progesterone combination alternative. This is important information.