Menopausal hormone therapy (formerly known as hormone replacement therapy or HRT) is the use of medications containing female hormones to replace hormones the body no longer makes naturally after menopause. Its purpose is to treat hot flushes and other symptoms of menopause, most commonly in cases of early menopause (before the age of 45) or when menopausal symptoms are severe.
Due to risks associated with menopausal hormone therapy (MHT) the New Zealand Ministry of Health recommends use of MHT in the lowest possible dose for the shortest possible time, and no longer recommends the use of hormone replacement for the prevention of heart disease
, or as a first line treatment for osteoporosis
, oestrogen and progesterone production is reduced. Menopausal symptoms, such as hot flushes, sweats, and vaginal dryness, can occur as the body adjusts to these hormonal changes. The risk of developing osteoporosis (bone thinning) also increases during menopause.
The duration of menopausal symptoms varies considerably between women. On average, symptoms last for around two years. Some women pass through the menopause without noticing any symptoms, while others report severe symptoms.
Preferred terminology for this treatment has changed in recent years from hormone replacement therapy (HRT) to menopausal hormone therapy (MHT) to differentiate it from treatment for other conditions, such as growth hormone replacement.
MHT delivery methods and regimens
MHT (be it oestrogen by itself or with progesterone) may be available in the following ways:
- Tablets taken by mouth
- Skin patches or gels
- Vaginal creams, pessaries or rings
- Implants under the skin
- Intrauterine device (IUD).
Not all delivery methods will be appropriate for all women. This should be discussed with the doctor or specialist who is prescribing the therapy. Different regimens of MHT work in different ways and produce different effects. Some regimens mimic the menstrual cycle, so that monthly bleeding occurs. Continuous combined oestrogen and progesterone leads to an absence of periods in most women.
Women who have had a hysterectomy
are likely to be prescribed oestrogen alone. Women who have a uterus are more likely to be prescribed a regimen that includes progesterone. This is to protect against cancer of the endometrium (the lining of the uterus).
Before prescribing MHT the doctor will take a full medical history. The doctor should be advised if the woman has a history of any of the following conditions as MHT may not be appropriate in these circumstances:
MHT may also not be appropriate for women who have severe varicose veins
, are obese or who smoke.
MHT benefits and risks / side effects
When considering MHT it is important to discuss the potential benefits and risks of the treatment with a doctor. The risks may vary depending on whether oestrogen is given alone or in combination with progesterone, and depending on the woman's current age and age at menopause. The dose and type of oestrogen, other health factors such as risk of cardiovascular disease or cancer, and family medical history will also contribute to the assessment of risk in an individual person's circumstances.
A patient and her doctor may conclude that the potential benefits of MHTmay outweigh the risks. Benefits of MHT include:
Disadvantages of MHT include irregular bleeding with some hormone regimens and side effects such as breast tenderness, headaches, bloating and weight gain. Health risks associated with MHT may include:
- Increased risk of breast cancer
- Increased risk of heart attack
- Increased risk of blood clots, which can dislodge and travel to the lungs (causing pulmonary embolism) or brain (causing stroke)
- Increased risk of ovarian cancer (with oestrogen-only therapy)
- A slightly increased risk of gallstones
- A slightly increased risk of endometrial cancer.
If MHT is prescribed, it should be used in the lowest possible dose for the shortest possible time. Continued use of MHT should be reviewed with your doctor on a yearly basis.
For further advice about menopause and MHT contact your GP or Practice Nurse.
Mayo Clinic (2015). Hormone therapy: Is it right for you? (Web Page). Rochester, NY: Mayo Foundation for Medical Education and Research. http://www.mayoclinic.org/diseases-conditions/menopause/in-depth/hormone-therapy/ART-20046372?pg=1 [Accessed: 29/08/17]
American College of Obstetricians and Gynecologists (2015). Hormone therapy (Patient Education Fact Sheet). Washington, DC: American College of Obstetricians and Gynecologists. https://www.acog.org/~/media/For%20Patients/pfs003.pdf
NHS Choices (2016). Hormone replacement therapy (HRT) (Web Page). Redditch: National Health Service (NHS)
England. http://www.nhs.uk/Conditions/Hormone-replacement-therapy/Pages/Introduction.aspx [Accessed: 29/08/17]
BPACNZ (2016). Oestradiol patches now fully subsidised: what is their place in the treatment of menopausal symptoms? https://bpac.org.nz/2016/mht.aspx [Accessed 12/09/18]
Last Reviewed – September 2017