All about hormone replacement therapy (HRT)

The benefits and risks of taking HRT to treat the symptoms of menopause

Menopause is the natural point in a woman’s life when her ovaries stop producing the hormones estrogen and progesterone and her menstrual periods stop. This usually happens between the ages of 45 and 55 but can vary. A woman may reach menopause early as a side effect of medical treatment such as chemotherapy or having her ovaries removed.

Symptoms of menopause include hot flashes, mood swings and trouble sleeping, but every woman’s experience is different. Some women may not be bothered by symptoms, while others may find it hard to cope with them. Treatment options are available to help ease symptoms.

Why would a woman in menopause take HRT?

Some women take hormone replacement therapy (HRT) to ease menopausal symptoms. HRT is medicine that contains hormones that the ovaries make less of as women age and reach menopause.

HRT can be taken as estrogen only or as a combination of estrogen plus progestin (combined HRT). Combined HRT is most commonly used. Estrogen-only HRT can increase the risk of uterine cancer (cancer of the uterus), so it is usually only recommended for women who have had a hysterectomy to remove their uterus.

Taking estrogen alone can cause cancer in the lining of the uterus, but women who have had their uterus removed (hysterectomy) can take estrogen alone as they no longer have this cancer risk. Combined HRT is more commonly used by women with a uterus.

What are the benefits of HRT?

Combined HRT may help relieve menopausal symptoms, protect against osteoporosis (thinning of the bones) and reduce the risk of colon cancer.

What are the risks of HRT?

Research shows that long-term use of combined HRT (for 5 or more years) increases the risk of breast and ovarian cancer, heart disease, stroke and pulmonary embolism (blood clots in the lungs). The research suggests that the risks of long-term combined HRT use outweigh the benefits for most women.

The decision to take HRT is personal and should be made with the help of your doctor. Concerns about cancer, heart disease and stroke should be discussed when considering the benefits and risks of HRT.

Our recommendation

The Canadian Cancer Society recommends that women avoid taking HRT for any reason other than to relieve severe menopausal symptoms that have not responded to other treatment.

If you are thinking about taking HRT, talk to your doctor about the benefits and risks of taking it. These include:

  • how severe your menopausal symptoms are
  • your individual and family history of heart disease, breast and ovarian cancer, osteoporosis and dementia
  • how long you will be taking HRT

If you and your doctor decide that taking HRT is right for you, the lowest effective dose should be used for the shortest period of time possible.

HRT and cancer

There is strong evidence that using HRT raises a woman’s risk of breast, ovarian and uterine cancers. At the same time, it may lower the risk of colorectal cancer.

HRT and breast cancer

Combined HRT for menopause is a known cause of breast cancer, mainly in women who recently used or are still using the therapy. There is also some evidence suggesting that estrogen-only HRT may also increase the risk of breast cancer.

HRT and ovarian cancer

Studies suggest that both combined and estrogen-only HRT increase a woman’s risk of ovarian cancer – but the risk is low.

HRT and uterine cancer

Research shows that using estrogen-only HRT increases the risk of uterine cancer.

HRT and colorectal cancer

Some studies suggest that users of combined or estrogen-only HRT may have a lower risk of colorectal cancer, while others do not. HRT is not recommended to prevent colorectal cancer.

HRT after cancer

If you have a history of cancer and are thinking about taking HRT, you should know the risks.

  • Women with a history of breast cancer may be advised not to take HRT. This is because there are concerns that the estrogen in HRT may cause breast cancer to come back. Different studies tell us different things about the effects of HRT on women with breast cancer, so the risk is not yet fully understood.
  • HRT may be an option for women at a higher risk for breast cancer. Although women with an increased risk for breast cancer are usually advised not to take HRT, it might be advised if they have proper counselling and follow-up.
  • Women with a history of uterine cancer may be advised not to take HRT. Women who have had higher stage and higher grade uterine tumours have a higher risk of the cancer coming back.

Alternatives to HRT

Women who experience menopausal symptoms often seek relief in ways other than HRT. Not all of the alternatives to HRT have been scientifically proven, but many women do find them helpful.

What you can do to help sleep troubles

  • Exercise. Being active lowers stress and improves your overall well-being, which may help you sleep better.
  • Try relaxation techniques. Deep breathing, massage or yoga may help reduce your stress levels.
  • Sip chamomile tea or tea with valerian root at bedtime. Avoid caffeine and alcohol – they can make menopausal symptoms worse.

What you can do to control hot flashes

  • Get as much exercise as you can.
  • Choose light clothing and wear it in layers that can be removed.

What you can do to relieve vaginal dryness

  • Use a water-soluble lubricant or moisturizer available at your pharmacy.
  • Ask your doctor about a vitamin E vaginal suppository or cream to help relieve symptoms.

Are bioidentical hormones more effective and less risky than HRT? 

Some hormone products, which may be called bioidentical hormones, are available without a prescription. Bioidentical hormones are made from plant sources and are basically the same as hormones made by our bodies. You may have heard claims that these products are more natural, effective and safe than HRT, but there is no scientific evidence to prove this.

Not all of the alternatives to HRT have been tested to evaluate side effects. HRT may still be useful to ease the symptoms of menopause on a short-term basis if other treatments do not work and the symptoms are severe.

Always check with your doctor before deciding on HRT, herbal products or lifestyle changes.