A recent Lancet paper (1), updating the evidence on the association between Hormone Replacement Therapy (HRT) and risk of breast cancer, made for prominent headlines. These ranged from “Breast cancer risk from using HRT is ‘twice what was thought’” (Guardian), to the more dramatic “PAUSE IT: HRT treatment for menopause increases risk of breast cancer by a THIRD, experts warn” (The Sun), to the simply wrong ‘Breast cancer: HRT found to double risk of developing disease in worrying new study’ (Daily Express). These are potentially very worrying headlines, and women’s concern was expressed on social media and countered by explanation and reassurance from organisations such as Menopause Matters.

One issue is that the Lancet paper reviews the evidence from epidemiological rather than experimental studies. The randomised Womens’ Health Initiative trials have, for example, recently reported that women receiving oestrogen post-hysterectomy had a lower risk of breast cancer.

But, assuming that the conclusions of the Lancet paper are correct, how could these risks be communicated in a more helpful way?