When I ask women in my clinic why they are worried about taking hormone replacement therapy (HRT), the most common answer is their concern about the increased risk of breast cancer. Many women are very worried about this risk and it leads to much concern and confusion. There is evidence that taking combined HRT over the age of 50 years is associated with a small increased risk of breast cancer.
The findings of a study published in the British Journal of Cancer this week have suggested that the increased risk of breast cancer among women taking the more common combined HRT in the longer term is slightly higher than previous studies have shown; their results showed closer to a threefold increase rather than a doubling for those taking HRT for over 15 years.
However, there is no new cause for alarm. The results of this study are similar with other studies in that women who are only taking oestrogen (so those women who have had a hysterectomy) do not have an increased risk of breast cancer.
It appears to be that it is the type of progestogen that is important and the newer type of progestogen, micronised progesterone, was not mentioned in this study. It is so important for women to understand that there are so many other risk factors for breast cancer. These include being overweight or obese, being older, drinking alcohol and smoking.
The risk of developing breast cancer is actually greater if you are overweight than if you take HRT. Any increased risk of breast cancer with taking HRT is reversed on stopping HRT. The British Menopause Society and the International Menopause Society have also produced documents that agree with my views.
Women who are under 51 years of age taking HRT do not have any increased risk of breast cancer by taking HRT, because they are simply taking hormones that their body would otherwise be making.