HRT Information for Patients

This leaflet aims to answer your questions about taking HRT to treat your menopausal symptoms. If you have any questions or concerns, please speak to the doctor or nurse caring for you. This leaflet should be read alongside any patient information provided by the manufacturer.

The risks

Breast Cancer

A study published in August 2019 shows that all forms of HRT are associated with an increased risk of breast cancer.

A new study has confirmed that women who use HRT for longer than 1 year have a higher risk of breast cancer than women who never use HRT. The risk of breast cancer falls after HRT is stopped but some increased risk remains for more than 10 years compared to women who have never used HRT

In the UK about 1 in 16 women who never use HRT are diagnosed with breast cancer between the ages of 50 and 69 years. This is equal to 63 cases of breast cancer per 1000 women.

Over the same period (ages 50–69 years), with 5 years of HRT use, the study estimated:

  • About 5 extra cases of breast cancer per 1000 women using estrogen-only HRT
  • About 14 extra cases of breast cancer per 1000 women using estrogen combined with progestogen for part of each month (sequential HRT)
  • About 20 extra cases of breast cancer per 1000 women using estrogen combined with daily progestogen HRT (continuous HRT)

Comparing other known risk factors for breast cancer with HRT risk can be helpful in putting risk into perspective:

  • More than 2-3 units of alcohol per day increases risk by 1.5x
  • Postmenopausal obesity increases the risk by 1.6x

Clotting Problems – Venous thromboembolism (VTE)

Tablet (oral) form of HRT has been shown to cause a small increase in risk of blood clot (e.g. deep vein thrombosis).The greatest risk is within the 1st year of use and is most relevant to women who have other risk factors, such as family history of clots, or obesity. There is strong evidence that transdermal (patch or gel) estrogen may not confer the same increased risk

Cardiovascular disease

Final analysis of the WHI trial showed that there was no increased risk with estrogen only HRT and in fact there was a reduction in heart disease compared to placebo (inactive tablet).

For women taking combined HRT, there was an increased risk only in women who were 20 or more years post menopausal, and the increase was in the 1st year of use with no overall increase by the end of the trial.

HRT used in the early menopausal years for control of menopausal symptoms is very unlikely to be harmful to the heart and may yet prove to be beneficial.

Endometrial cancer

Estrogen only therapy given to women with a uterus (womb) increases the risk of endometrial hyperplasia (thickening of the lining of the uterus) and eventually endometrial cancer. Daily estrogen combined with progestogen given for 10 to 14 days per month (sequential HRT) reduces this risk but does not eliminate it. Sequential HRT given for more than 5 years does increase the risk of endometrial cancer by a small amount but no increased risk appears to apply to estrogen combined with daily progestogen (continuous combined or period-free HRT).

Ovarian cancer

The studies are unclear, the two major HRT studies having opposite results. The million Women study suggested an increased risk. This increase was of the order of 1 extra case for every 2,500 women taking HRT for 5 years and so if there is an association, this risk is very small.

Are there any side effects?

Many women experience side effects in the first few months of taking HRT. If problems persist after three months of treatment then the type of HRT may be changed. Women react differently to HRT, so there is no one preparation that is better than any of the others. It is often a personal choice as to the type of preparation we try first.

Weight gain

It has been scientifically proven that women gain weight during the menopause, so any weight gain may not be a result of HRT. Your body’s fat distribution also changes, with an increase in fat around the waist and less around the hips and buttocks. You can also experience water retention when on HRT. If this happens then it may be worth trying a different preparation of HRT.


Irregular bleeding in the first few months of taking any form of HRT is quite common and usually settles. Any bleeding after the first six months will need to be investigated with an ultrasound and possible gynaecology referral.


Some women complain of nausea associated with HRT. This can be reduced by taking the HRT tablet at night with food instead of in the morning, or by changing from tablets to another type of HRT.

Skin irritation

This can happen with patches and occasionally gel. Sometimes the patches may fall off.

Other side effects that can occur and normally settle include: breast tenderness and enlargement, leg cramps, bloating, headache, pre-menstrual symptoms, lower abdominal pain, backache, depressed mood, acne/greasy skin.

What should I do if I forget to take the medicine?

If you forget to take your HRT do not take the doses that you have forgotten, just take the next dose when you remember.

Do I still need to use contraception when taking HRT?

HRT does not provide contraception. You need to continue using contraception for 1 year after your last period if this happens after the age of 50 years. If your last period happens before you are 50 years of age then you need to continue using contraception for 2 years.

Useful sources of information

Daisy Network

A charity supporting those affected by premature menopause


Women’s Health Concern

A charity providing advice and information for women


NHS website


Menopause Matters