Menopause Hormone Therapy Risks?

Menopause Hormone Therapy Risks?

What are Menopause Hormone Therapy Risks? Menopause Hormone Therapy (MHT) also referred to as Hormone Replacement Therapy (HRT), is a commonly prescribed treatment offered to women for menopausal symptoms, for relief from hot flushes, night sweats, and mood swings, to name but a few.

These symptoms can be debilitating, not only for the woman herself but can impact others around her, in work and at home. Despite this, many women have concerns about the potential risks associated with MHT.

In this article, we will discuss some of the potential risks including cancer, stroke, blood clots, and cardiovascular disease, and analyse increased risk between women who take MHT and those who do not.

MHT may be prescribed in a sequential regime, oestrogen daily with progestogen taken for two out of every four weeks, to mimic the menstrual cycle or in a combined regime, where oestrogen and progestogens are taken every day.

Understanding the risks


One of the primary concerns surrounding MHT is the association with cancer and the one most women tend to worry about is breast cancer.

Studies have shown that there may be a small increase in the risk of breast cancer for women using MHT when using combined oestrogen and progestogen therapy. The oestrogen in the majority of MHT prescribed is oestradiol. This is the most potent of the oestrogens that the ovaries make. There are many different types of progestogens, the majority are synthetic.

It is the type of progestogen within the MHT that is associated with the small, but real increased risk of breast cancer. According to data published by the NICE guidelines and the BMS, there will be an extra 2 cases of breast cancer per thousand women per year. This risk is considerably less than drinking 2 or more units of alcohol per day.

In women without a uterus, there is no need to take progestogens and so the risk is even smaller and studies have shown that there is no risk with oestrogen taken transdermally.
Furthermore, studies have shown that in women who develop breast cancer whilst on MHT their chances of survival are higher than if not on MHT.

The risk of endometrial cancer, cancer of the lining of the womb is slightly increased with sequential formulations, however when MHT is taken in a continuous form, oestrogen and progestogen daily, it actively protects the endometrium.

Women with a high BMI, over 30, should discuss the dose of progestogen they are taking with their HCP as obesity is associated with an increased risk of endometrial cancer irrespective of whether or not they take MHT.

Stroke and Blood Clots

Another risk associated with MHT is an increased chance of stroke and blood clots. The risk appears to be slightly higher in women using MHT, particularly for those above the age of 60. Despite this the overall risk remains low.

However, this risk is only seen in women taking oral medication with no increased risk with transdermal methods of oestrogen, such as gels, sprays or patches. progestogens should also be prescribed for women with a uterus.

In fact, transdermal MHT can be prescribed safely even if there is a personal history of clots or strokes.

Cardiovascular Disease

Cardiovascular disease, which includes heart attacks and other heart-related conditions, such as angina, is a concern for women on MHT. Studies have shown conflicting results regarding the risk of cardiovascular disease associated with MHT. Some research suggests a slightly increased risk, while others indicate no significant difference between MHT users and non-users.

We do however need to look at the studies more closely and look at the timing of starting MHT.

Starting MHT within 10years of the last menstrual period (LMP) has been shown to be actively protective. Overall, the risk of cardiovascular disease is low for women using MHT.

It is essential for women with existing cardiovascular risk factors to discuss their situation with their healthcare provider before starting MHT.

Transdermal MHT or Oral MHT, Risks?

Transdermal MHT, delivered through patches, sprays or gels applied to the skin carries no risk of adverse effects when compared to oral MHT. When MHT is taken orally, it undergoes first-pass metabolism in the liver, which can lead to an increased risk of blood clots. In contrast, transdermal MHT bypasses the liver, removing this risk. Additionally, transdermal MHT may be a suitable option for women who cannot or prefer not to take hormone therapy orally.

So, does MHT have lots of risks?

MHT is a beneficial treatment option for managing menopause symptoms, providing relief and improving the quality of life for many women. While there are some risks associated with MHT, these are minimal and the overall increase in risk for conditions like cancer, stroke, blood clots, and cardiovascular disease is very small.

MHT will actively protect women from common diseases associated with aging and poor lifestyle. These include osteoporosis and diabetes as well as those diseases already mentioned. The long-term sequelae of these diseases can be debilitating.

Exciting studies also suggest that there is a possible protective effect from dementia if MHT is started within five years of the LMP, but we await further definitive research.

What is crucial is that women are given the RIGHT information at the RIGHT time for the RIGHT reasons by Health Care Professionals (HCP’s)so that they can make an informed choice about their health in their post-reproductive years.

Remember, MHT is not suitable for everyone, and alternative treatments or lifestyle changes may be recommended for some individuals.
As new research and guidelines emerge, it is crucial to stay informed and have open discussions with Healthcare Professionals to make the best decisions for your health and well-being.

Written for

By Dr Joanne Hobson, Clinical Lead Director of The Menopause Consortium, MBBB, DRCOG, British Menopause Society Menopause Specialist and Member of the Institute of Psychosexual Health