I am not an advocate of HRT, and that is from someone who took it for a year to cope with menopause symptoms and found like many women before me that the side effects were not liveable with. At that time I was not aware of the health risks associated with HRT, but today that is simply not the case as every week brings a new story of the potential problems associated with it.
Having said that, there are women who will for their own reasons, wish to take HRT and that is entirely their choice. What is worth considering if you are one of those women is that the longer you wait, the lesser the risk. In fact for women who stop hormone therapy, the risk of breast cancer falls to the level of non-users after two years.
Women who begin using hormone therapy close to the time of menopause are at greater risk of breast cancer than those who wait five years or more, a large prospective study found.
To clarify whether the timing of starting treatment influences breast cancer risk, Beral and her collaborators from the Million Women Study at Oxford recruited almost 1.3 million women from the U.K. between 1996 and 2001, obtaining information on socio-demographic and health factors, as well as their history of hormone use.
The average age of the women was 56.6 years at enrolment. A total of 55% had used hormone therapy at some point and 35% were current users. Through the data they analysed, they found that up to 15,759 breast cancers were diagnosed of which 61% were in women who had ever used hormone therapy and 45% in women currently using the hormones.
There were significant differences in women who were taking estrogen-only and estrogen-progestin formulations of HRT. Not surprisingly, the current users of estrogen-only HRT who had begun taking it soon after menopause had a significantly higher risk of breast cancer than was found in non-users of HRT. And perhaps even more surprising is the fact that the risk among women currently taking estrogen-progestin formulations was actually greater than for those taking estrogen alone.
So if you are contemplating HRT, or know a woman who is, then the best advice to reduce breast cancer risk is to postpone taking it for at least five years after menopause begins.