Hormone replacement therapy (HRT) - Types of HRT

Hormone replacement therapy (HRT) replaces female hormones that a woman’s body is no longer producing, due to the menopause.

These hormones are:

• oestrogen – which is taken from either plants or the urine of pregnant horses
• progesterone – HRT uses a synthetic version of progesterone called progestogen, which is easier for the body to absorb

Choosing the right HRT for you

Finding the right type of HRT can be tricky.

A low dose of HRT hormones is usually recommended to begin with. It is best to start with the lowest effective dose, to minimise side effects. If necessary, you can increase your dose at a later stage.

Persevere with HRT and wait a few months to see if it works well for you. If not, you can try a different type or increase the dose. Talk to your GP about any problems you have with HRT.

While there are more than 50 different preparations of HRT, the three main types are discussed below.

Oestrogen-only HRT

Oestrogen-only HRT is usually recommended for women who have had their womb removed during a hysterectomy. There is no need to take progestogen because there is no risk of womb (uterus) cancer, sometimes called endometrial cancer.

Cyclical HRT

Cyclical HRT, also known as sequential HRT, is often recommended for women who have menopausal symptoms but still have their periods.

There are two types of cyclical HRT:

• monthly HRT – where you take oestrogen every day and progestogen at the end of your menstrual cycle for 12-14 days
• three-monthly HRT – where you take oestrogen every day and progestogen for 12-14 days, every 13 weeks

Monthly HRT is usually recommended for women having regular periods.

Three-monthly HRT is usually recommended for women experiencing irregular periods. You should have a period every three months.

It is useful to maintain regular periods so you know when your periods naturally stop and when you are likely to progress to the last stage of the menopause.

In some cases, a woman using cyclical HRT may continue having periods after the menopause (when she is post-menopausal).

Continuous combined HRT

Continuous combined HRT is usually recommended for women who are post-menopausal. A woman is usually said to be post-menopausal if she has not had a period for a year.

As the name suggests, continuous HRT involves taking oestrogen and progestogen every day without a break.

Contraception, pregnancy and HRT

Oestrogen used in HRT is different from oestrogen used in the contraceptive pill, and is not as powerful.

This means it's possible to become pregnant if you are taking HRT to control menopausal symptoms. In some cases, a woman can be fertile for up to two years after her last period if she is under 50, or for a year if she is over 50.

If you don't want to get pregnant, you can use a non-hormonal method of contraception, such as a condom or diaphragm.

An alternative is the intrauterine device (IUD), which is also licensed for heavy periods and as the progestogen part of HRT. You will need to add oestrogen as either a tablet, gel or patch.

An IUD needs to be inserted by a trained clinician and will give protection for 5-10 years, depending on the type.