For many years the medical advice was that a woman who had breast cancer should not take hormone replacement therapy (HRT).  This was because of concerns that the hormones contained in HRT might cause the cancer to come back, or a new breast cancer to develop. Some specialists questioned this view, arguing that there was no real evidence to support it, and that some women did get very troublesome menopausal symptoms could get a real benefit from HRT. As a result several clinical trials were set up to find out more about the risks and benefits.

Recently one of the first of these studies, carried out in Sweden, has reported its results.  These showed that women who have had breast cancer who took HRT were much more likely to have a recurrence of their cancer, or develop a new breast cancer compared with women who did not take HRT. Another recent trial (in women without breast cancer) showed that long term HRT in women over the age of 50 increased their risk of breast cancer.

There is another trial looking at the risks and benefits of HRT after breast cancer but the results of this trial will not be available for some years. Meantime the current medical advice is that women who have had breast cancer should avoid taking HRT if at all possible. Some specialists may still prescribe it if a woman with breast cancer has severe menopausal symptoms which have not been helped by anything else.

There are some alternatives to HRT, which may help control menopausal symptoms, and treatments that can reduce the risk of bone thinning (osteoporosis). These are discussed in other answers in this section. It is also likely that the recent trial results will lead to more research to find better and safer alternatives to current HRT.