Hormone replacement therapy is used to help balance estrogen and progesterone in women around the time of menopause.

Also known as hormone therapy (HT) or menopausal hormone therapy (MHT), hormone replacement therapy (HRT) can help relieve sweating, hot flashes, and other symptoms of menopause. It can also reduce the risk of osteoporosis.

Some types of HRT contain both progesterone and estrogen, some only estrogen, and sometimes testosterone is used.

Hormone replacement treatments are also used in male hormonal therapy and treatment for individuals who undergo a sex change.

This article focuses on HRT as a way of relieving symptoms in women around the time of menopause.

Fast facts on hormone replacement therapy (HRT)

Here are some key points about HRT. More detail is in the main article.

  • Hormone replacement therapy is an effective way to relieve symptoms of perimenopause and menopause.
  • It can reduce the incidence and severity of hot flashes, and also the risk of osteoporosis.
  • Past studies have suggested a link with cancer, but this is still being investigated.
  • It may help keep skin young, but it cannot reverse or delay the overall effects of aging.
  • Any woman who is considering HRT should talk to a physician who knows her medical history.

[hormone replacement therapy HRT]Share on Pinterest
Menopause can bring discomfort and health risks, but HRT can help reduce these.

Progesterone and estrogen are important hormones in a woman's reproductive system.

Estrogen stimulates the release of eggs, and progesterone prepares the womb for egg implantation.

As a natural part of the life process, the supply of eggs diminishes over time. As the number of eggs falls, so does estrogen production.

Most women will start to experience these changes in hormone levels during their late 40s. This can lead to hot flashes and other problems.

perimenopauseFor some time, a woman will continue to menstruate, although the changes are happening. This is called perimenopause. It can last from 3 to 10 years. Average duration is 4 years.

MenopauseWhen the last period occurs, at an average age of 51 years, the woman is in menopause.

Postmenopause: One full year after the last period, menopause ends, and the woman enters the postmenopausal stage. Symptoms normally decline within 2 to 5 years, but it can take 10 years or more.

The increased risk of osteoporosis continues after menopause.

Apart from the natural aging process, menopause can be triggered by a hysterectomy that includes removal of the ovaries, or cancer treatment.

Smoking can also speed up the arrival of menopause.

Effects of menopause

Changing hormone levels can cause severe discomfort and some health risks.

The following may occur:

  • vaginal dryness
  • bone thinning, or osteoporosis
  • urinary problems
  • thinning hair
  • sleep problems
  • hot flashes and night sweats
  • moodiness
  • lower fertility
  • irregular periods
  • concentration and memory difficulties
  • smaller breasts and an accumulation of fat in the abdomen

HRT can bring some relief.

HRT was once widely used for reducing symptoms of menopause and protecting against osteoporosis and cardiovascular disease.

However, its benefits were questioned after two studies using data from the Women's Health Initiative (WHI) were published, in 2002 and 2003. Findings linked HRT to endometrial, breast, and ovarian cancer.

This caused many people to rethink the use of HRT, and it became less widely used.

Now, further research has questioned those investigations. Critics point out that the findings were mixed, and since different hormone combinations can have different effects, the results did not really show how hazardous or how safe HRT might be.

In the case of breast cancer, a combination of progesterone and estrogen was linked to one extra case of breast cancer per year for every 1,000 women.

Newer studies have suggested that the benefits of HRT may outweigh the risks, but there is still some confusion.

A report published in The BMJ in 2012 concluded that "HRT may or may not increase the risk of breast cancer."

Other recent studies have suggested that it may:

It is now thought that HRT may not be so hazardous for some women, after all. It is currently approved to treat menopausal symptoms and to prevent or treat osteoporosis.

However, for anyone who is thinking of using HRT, this must be a careful and informed decision taken with a doctor who understands the individual's risks.

More evidence is needed, and research continues. It should also be remembered that aging is a natural human process. If HRT can protect against some changes that occur in women, it cannot prevent all aspects of aging.

HRT may not be suitable for women who have a history of:

The risk of breast cancer is now thought to rise if HRT is used for over 5 years. The risk of stroke or blood-clotting problems is not believed to be high for women aged 50 to 59 years.

It should not be used by women who are or who may become pregnant.

One fear about HRT is that it will cause women to gain weight. Women often gain weight around menopause, but research has shown that this is not necessarily due to HRT.

Other possible reasons for weight gain around this time include a drop in physical activity, a redistribution of fat as hormone levels change, and an increase in appetite resulting from a fall in estrogen.

Maintaining a healthy diet and getting plenty of exercise can help reduce weight gain.

Share on Pinterest
HRT can come as pills, creams, patches, or in a vaginal ring.

Common types of HRT use different combinations and delivery of the hormones.

Estrogen-only HRT: Women who have had a hysterectomy where their uterus, or womb, and ovaries have been removed do not need progesterone.

Cyclical, or sequential HRT: Women who are still menstruating but have perimenopausal-like symptoms can use this. Cycles may be monthly, with an estrogen plus progestogen dose at the end of the menstrual cycle for 14 days, or a daily dose of estrogen and progestogen for 14 days every 13 weeks.

Continuous HRT: This is used during postmenopause. The patient takes a continuous combination of estrogen and progestogen.

Long-cycle HRT: this causes withdrawal bleeds every 3 months. Its safety has been described as "questionable."

Local estrogen: This includes vaginal tablets, creams, or rings. It can help with urogenital problems, including dry vagina and irritations.

How does the patient take HRT?

The doctor will prescribe the lowest possible dosage to treat symptoms. This may take some trial and error.

Ways of delivering HRT include:

  • creams or gels
  • vaginal rings
  • tablets
  • skin patches

When HRT is no longer needed, patients will stop using it gradually.

A woman who is experiencing perimenopause can use alternative ways to relieve symptoms.

Share on Pinterest
Alternative ways of reducing symptoms include the use of a fan.

These include:

  • Reducing consumption of caffeine, alcohol, and spicy food
  • Not smoking
  • Exercising regularly
  • Wearing loose clothing
  • Sleeping in a well ventilated, cool room
  • Adding a fan to the bedroom or cooling gel pad or pillows

Some SSRI-type antidepressants can help treat hot flashes, and the antihypertensive drug, clonidine, may help.

Anecdotal accounts say that consuming ginseng, block cohosh, red clover, soya beans and Kava help with menopausal symptoms. It is worth noting that the United States (U.S.) Food and Drug Administration (FDA) does not recommend or regulate herbal or supplement treatment, and research has not confirmed their benefits.

HRT is an effective treatment for symptoms such as sweating and hot flashes, but women should speak to their doctor and consider carefully before taking it.