Breast cancer and HRT Factsheet

Breast cancer is very common. Each woman in the UK has a 1 in 8 chance of developing breast cancer, regardless of whether they take HRT or not. This means that if you take HRT your risk of breast cancer is 1 in 8, and for women who do not take HRT the risk is also 1 in 8.

There are certain factors that increase your risk of developing breast cancer and these include simply getting older, being overweight, drinking alcohol, smoking, not exercising regularly, and having young family relatives who have had breast cancer. However, many women develop breast cancer without any of these risk factors.

At Newson Health, the most common reason we hear from women who are scared of taking HRT, is they are worried about the risk of breast cancer. Here are some facts about HRT and breast cancer which we hope will reassure you.

The most common reason we hear from women who are scared of taking HRT, is they are worried about the risk of breast cancer. Here are some facts about HRT and breast cancer which we hope will reassure you.

Young women taking HRT do not have a greater risk of breast cancer

What many patients and doctors do not realise is that women who are under 51 years of age have absolutely no increased risk of getting breast cancer, regardless of the length of time they take HRT for. This is because women who take HRT when they are young are simply replacing the hormones that their bodies should otherwise be producing. The average age of the menopause in the UK is 51 years.

It is really important that women and doctors are aware of this. If you do not have the correct type and strength of HRT when you are young, you will have an increased risk of developing osteoporosis (weakening of the bones) and heart disease. Taking HRT reduces these risks.

Women who have had a hysterectomy and take HRT do not have a greater risk of breast cancer

Numerous studies have shown that women who take estrogen­only HRT do not have a higher risk of breast cancer. Some studies have actually shown these women have a lower risk of breast cancer than women not taking HRT.

The increased risk of breast cancer with taking combined HRT is very low or not increased at all

Some studies show that taking combined HRT (i.e. HRT containing both estrogen and a progestogen) may be associated with a very small increased risk of breast cancer. However, the media have misinterpreted this information and presented the risk as far greater than it actually is, leading women to feel confused and anxious about the perceived risk of breast cancer.

The increased risk is related to the type of progestogen in the HRT. Taking micronised progesterone (the body identical progesterone) is not associated with an increased risk of breast cancer, for the first five years of taking it. After five years, the risk of breast cancer is very low and seems to be lower than the risk for a woman taking the older types of progestogen.

Even for women taking the older types of progestogen, the risk is very low. A recent review of all the research studies concluded that current scientific evidence (for older types of progestogen) does not confirm, or dispute, that taking HRT causes breast cancer.

The level of increased risk of breast cancer, with the older types of combined HRT, is similar to the level of risk of breast cancer that any women has if they are overweight or drink around two glasses of wine a day.

In addition, there is no evidence that shows there is an increased risk of death from breast cancer, in women who take HRT.

If you have a strong family history of breast cancer, or have had breast cancer yourself in the past, you might still be able to take some types of HRT. It is best to discuss your options with your GP, or a doctor who specialises in the menopause.