What is hormone therapy?

Hormone therapy (HT) is a treatment program in which a woman who has a uterus takes estrogen and progestin (a synthetic form of progesterone) to relieve menopause symptoms and to reduce the risk of osteoporosis, which becomes more common after menopause. Studies are being done to determine how long a woman needs to take HT to reduce these risks. Research has shown that estrogen replacement might increase a woman's life span. The majority of the benefits of HT appear to be linked with estrogen. Many women who have had hysterectomies (removal of the uterus through surgery) can take estrogen alone.

Estrogen is available in these forms: pills (taken by mouth), rings, skin patches, or vaginal creams or tablets. Progestin is usually taken in pill form but is also available in skin patch and vaginal gel form.

What are estrogen and progesterone?

Estrogen and progesterone are female hormones naturally produced by a woman's ovaries. Hormones control many functions throughout the body. Estrogen and progesterone help control a woman's menstrual cycle. Estrogen also influences how the body uses calcium (a mineral important for building and strengthening bones), helps maintain healthy levels of cholesterol in the blood, maintains the skin's elasticity, and helps keep the vagina and bladder healthy. As menopause nears, a woman's ovaries stop producing estrogen and progesterone, greatly lowering levels of these hormones in the body. Lowered estrogen levels might cause menopause symptoms and can lead to changes in a woman's body. HT helps replenish these hormones, lessening the symptoms of menopause.

What symptoms of menopause does estrogen treat?

• Hot flashes (sudden sensations of warmth that spread over the upper body)
• Vaginal dryness
• Dry skin
• Sleeplessness
• Irritable bladder and bladder problems

What are the long-term benefits of hormone therapy?

Studies have shown that long-term use of estrogen:

• Reduces your risk of osteoporosis (thinning of bone) by preserving bone mass (Osteoporosis weakens bones and makes them more likely to fracture.)
• Might reduce your risk of other conditions related to low estrogen levels, such as colon cancer

HT is not specifically used to prevent heart disease.

Estrogen might help to maintain healthy levels of cholesterol in the blood, improve blood flow to the heart, and reduce blood-clotting factors in some women. A woman who experiences premature menopause and does not take estrogen is two to three times more likely to develop heart disease than a woman who does take estrogen therapy. However, taking estrogen after the diagnosis of heart disease does not help prevent heart attacks; and for the average postmenopausal woman, taking HT does not decrease heart disease. In fact, it increases the risk of blood clots.

Further research might establish that estrogen:

• Decreases tooth loss
• Reduces your risk of colon cancer and colon polyps
• Reduces the risk of diabetes mellitus
• Improves your mood and overall sense of mental well-being
• Reduces the risk of macular degeneration and cataracts

Doctors have not yet determined how long a woman needs to take estrogen to reduce these risks.

What are the types of HT?

There are two main types of HT:

1. Estrogen therapy — Estrogen is taken alone. Doctors most often prescribe a low dose of estrogen to be taken as a pill every day. You should take the lowest dose of estrogen needed to relieve menopause symptoms and/or to prevent osteoporosis.

2. Progestogen-estrogen therapy — Progestogen-estrogen therapy combines doses of estrogen and progesterone. (Progestin is a synthetic form of progesterone.) A typical combination therapy consists of taking estrogen daily with progesterone for two weeks of every month. Both medicines are stopped after three weeks. For women who experience withdrawal symptoms from estrogen, estrogen might be given continuously with progesterone added every two weeks. Estrogen and a lower dose of progesterone also might be given continuously to prevent the regular, monthly bleeding that occurs when progesterone is taken cyclically.

Why is progestogen taken?

When taken without progestogen, estrogen increases a woman's risk of cancer of the endometrium, the tissue lining the uterus. Estrogen stimulates cell growth in the endometrium. During a woman's reproductive years, endometrial cells are shed during menstruation. When the endometrium is no longer shed, estrogen can cause an overgrowth of cells in the uterus, a condition that can increase a woman's risk of endometrial cancer.

Progestogens reduce the risk of endometrial cancer by making the endometrium shed each month. As a result, women who take progestogen may have monthly bleeding. Monthly bleeding can be lessened and, in some cases, eliminated by taking progestin and estrogen together continuously. Women who have had hysterectomies do not usually need to take progestin.

Which form of medicine should I take?

The medicine, its dosage, and method of delivery should be chosen to match your needs, health status, age, and other factors. Some HT programs are selected to improve specific symptoms. For example, a vaginal estrogen cream or ring might be the best choice for a woman who wants to relieve vaginal dryness caused by menopause. However, creams, rings, or vaginal tablets cannot provide the dose of estrogen needed to reduce the risk of osteoporosis. A transdermal patch (skin patch) might be the best choice for a woman who has a liver condition or elevated triglycerides and wants to prevent osteoporosis. With this form, estrogen is absorbed directly into the bloodstream and bypasses the liver. Before you choose a hormone program, ask your health care provider to describe all of your treatment options.

What are the risks of HT?

Known health risks are:

• An increased risk of endometrial cancer (if a woman still has her uterus and is not taking progesterone along with estrogen)

Possible health risks are:

• Rare: Increased risk of breast cancer with long-term use (in women who take progestin-estrogen therapy)
• Increased risk of gallbladder disease
• Increased risk of blood clots (If they occur, they are more likely to appear within the first few months of use.)
• Rare: Increased blood pressure in some women

What are the side effects of HT?

Estrogen can cause side effects similar to the discomforts of menstruation, including:

• Leg cramps
• Headaches
• Water retention

Progestins can cause:

• Tender and swollen breasts
• Fatigue
• Irritability
• Monthly bleeding

Is HT safe for everyone?

With management, most women can take HT to relieve their menopausal symptoms. However, HT is not usually recommended for women who have:

• Recurrent or recent blood clots
• Current or past breast cancer (Exceptions are sometimes made.)
• Recurrent or recent endometrial cancer
• Abnormal vaginal bleeding
• Liver disease
• Stroke or high risk for stroke

HT might not be advisable for some women who have:

• Endometriosis
• Fibrocystic breast disease
• Uterine fibroids
• Gallbladder disease
• Increased risk of blood clots
• Migraine headaches
• Epilepsy
• Recent heart attack or known heart disease

Will HT make me gain weight?

Estrogen might cause you to retain water, which can lead to temporary weight gain. However, HT has not been shown to lead to weight gain. Your doctor might be able to reduce water retention by adjusting your dose of estrogen. Hormones do not cause weight gain nor do they prevent age-related weight gain common in sedentary American women.

How long should I take HT?

Since research on HT continues, women should re-evaluate their treatment plans each year. It is important to note that hormone therapy only reduces fractures while being taken.

How can I know if HT is right for me?

There are many factors to consider when deciding whether to take HT, including your current health status and medical history. Discuss your risk factors and medical history with your doctor. You should also weigh the risks and benefits of HT.

Here are some questions you can ask yourself and discuss with your physician:

1. Am I experiencing difficult menopause symptoms?
2. Do I have any medical conditions or inherited risk factors that might make HT unsafe for me?
3. Do I have any medical conditions or inherited risk factors that might make HT beneficial to me?
4. Have I considered other treatments?

Other treatments include:

• Anti-depressant selective serotonin reuptake inhibitors (SSRIs), such as venlaflaxine (Effexor^®), can be used to treat hot flashes.
• Clonidine (Catapres-TTS^®) and methyldopa (Aldomet^®) are medicines to relieve hot flashes (recommended only for women with high blood pressure).
• Calcitonin (Calcimar), alendronate sodium (Fosamax^®), risedronate (Actonel^®), IV Reclast^®, and raloxifene (Evista^®) are medicines to treat established osteoporosis.

You can also help ensure your health by:

• Exercising daily and not smoking
• Getting enough calcium (1,500 milligrams total a day after menopause) and Vitamin D (800 to 1,000 IU a day)
• Participating in regular aerobic and weight-bearing exercise
• Limiting fat to less than 30 percent of your diet
• Limiting how much cholesterol you eat
• Eating a diet rich in complex carbohydrates (whole grains, beans, vegetables, and fruits)
• Maintaining a normal body weight for your height
• Avoiding trans-fatty acids like "partially hydrogenated fats"
• Eating at least two servings of omega-3 fats like fish or flaxseed per week

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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 1/28/2008...#4263