The risk is twice as bad as previous studies had warned, and it increases the longer women take it. By the time a woman has taken it for 15 years or more, her risk has more than trebled, but the average time women take HRT is five or so years, and for them the risk is slightly under three times.
The risk seems to be only with the combined estrogen plus progestogen HRT, and there’s no risk associated with the estrogen-only version. The risk also recedes rapidly once a woman stops taking it, say researchers from the Institute of Cancer Research.
Although most studies for the past 15 years have seen an association with breast cancer, the latest one has discovered that the risk is twice as high. Previous studies hadn’t kept on top of the data, the researchers say, which would explain why the risk has been under-stated.
The findings also throw into question the more relaxed approach that was being promoted last year by the UK’s health guidance group, the National Institute of Health and Care Excellence (Nice), which felt the cancer risks had been exaggerated and that it was perhaps safe for women to start taking HRT again.