Hormone replacement therapy (HRT) replaces female hormones that a woman’s body is no longer producing, due to 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
HRT is available in all shapes and sizes, each designed to offer as wide a choice as possible. Furthermore there is also choice in how these hormones are introduced to the body. There are three main routes, and each will be appropriate for different women:
- Via the mouth as a tablet – this is the most common form of HRT
- Transdermal (through the skin) methods are less common but still very popular. They can take the form of an adhesive patch or a gel
- An implant injected beneath the skin to provide slow release of oestrogen over several months.
For vaginal and bladder symptoms, estrogen can be taken as a small vaginal tablet, cream or vaginal ring inserted within the vagina to provide local ‘nutrition’ with minimal absorption into the body.
Update Dec 2018
A review of recently published studies of long term use of vaginal estrogen has concluded that the bulk of evidence on use of low dose vaginal estrogen supports the safety of vaginal estrogen and no increase in the risk of endometrial cancer. Systemic absorption of vaginal estrogen is minimal and the effect is a local vaginal effect.
Types of HRT
Finding the right type of HRT can be difficult and you and your healthcare professional will need to work together on this. If you are not satisfied with the advice you are getting from your doctor it is your right to request a consultation with a menopause specialist.
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.
You will need to 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. It is important that you talk to your doctor about any problems you have whilst taking HRT.
While there are more than 50 different preparations of HRT, here is a summary of the three main types.
Oestrogen-only HRT is usually recommended for women who have had their womb removed (hysterectomy). There is no need to take progestogen because there is no risk of womb uterus cancer, sometimes called endometrial cancer.
Cyclical HRT, also known as sequential HRT, is often recommended for women who have menopausal symptoms but are still having 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 infrequent periods. You should have a period every three months.
In the same way as women who are taking a cyclical contraceptive pill will continue to have regular periods (withdrawal bleeds) even though the natural menopause may have happened, the same is true for women taking a cyclical HRT regime. If you want to know if you are postmenopausal you would need to stop HRT and either wait to see if you get a period, or after 4 weeks you could have a blood test (FSH) to find out.
Some women do not have a period whilst taking cyclical HRT, and that is fine. Don’t forget that HRT is not a contraceptive!
Continuous Combined HRT
Continuous combined HRT is usually recommended for women who are postmenopausal. A woman is usually said to be postmenopausal if she has not had a period for a year.
As the name suggests, continuous HRT involves taking estrogen and progestogen every day without a break.
Tibolone is the first ‘bleed-free’ HRT containing a synthetic hormone known as Tibolone which, when taken every day, has the combined effects of estrogen, progestogen and testosterone. Tibolone like other continuous therapies, is normally prescribed at least 12 months after the last menstrual period (postmenopause), so many women switch to these continuous types after taking a sequential HRT. Tibolone has been shown to be particularly beneficial in women who are known to have endometriosis and fibroids as it does not appear to stimulate these conditions.
The Role of the Mirena IUS
The Mirena coil or intrauterine system which is used by millions of women for contraception and for control of heavy periods, can be used to give progestogen into the uterus. Progestogen is essential to prevent the uterine lining (endometrium) from thickening. It means that the woman can have oestrogen through the whole body and progestogen in the only place it is needed. It lasts for 4 years.
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 condom or diaphragm.
Reviewed on: 01/05/2018 by Dr Karen Morton
Next Review: 01/05/2020
Hormone Replacement Therapy (HRT) Types. Retrieved from http://www.nhs.uk/Conditions/Hormone-replacement-therapy/Pages/How-it-works.aspx
HRT. Retrieved from https://www.womens-health-concern.org/help-and-advice/factsheets/hrt/
Pinkerton JA, Manson JA. Vaginal Estrogen in the Treatment of Genitourinary Syndrome of Menopause and Risk of Endometrial Cancer. Menopause. 2017;24(12):1329-1332