Menopausal hormone therapy and 20-year breast cancer mortality Valerie Beral, Richard Peto, Kirstin Pirie, Gillian Reeves  The Lancet  Volume 394, Issue 10204, (September 2019) DOI: 10.1016/S0140-6736(19)32033-1 Copyright © 2019 Elsevier Ltd Terms and Conditions

Figure 20-year breast cancer mortality rate ratio in relation to MHT use at the time of recruitment into the Million Women Study2 At recruitment (in mean year 1998), these women were free from breast cancer and were postmenopausal. MHT use would have continued for an average of about 5 years after recruitment in current users, but few who were past users or never-users at recruitment would have used MHT thereafter. Half the women were resurveyed about 8 years after recruitment, by which time there had been widespread cessation. The mean number of years of MHT use reported at resurvey by women in the above seven categories of use at recruitment (including MHT use before and after recruitment) had become, respectively, 0·1 years for never-users, 7·0 years (SD 3.7) and 13·5 years (5.5) for those who had been using oestrogen-only MHT, 6·6 years (3·4) and 11·8 years (4·3) for those who had been using oestrogen-progestagen MHT, and 1·2 years (2·1) and 7·8 years (4·4) in those who had been past users. MHT=menopausal hormone therapy. The Lancet 2019 394, DOI: (10.1016/S0140-6736(19)32033-1) Copyright © 2019 Elsevier Ltd Terms and Conditions