What is estrogen replacement therapy?
Estrogen replacement therapy (ERT) refers to taking regular doses of estrogen, usually the lowest effective doses, to replace the natural estrogen that decreases at menopause. After you have passed through menopause, your ovaries no longer produce eggs and your body produces less estrogen.
Estrogen is one of two major female hormones. The other is progesterone. For women who still have their uterus, progesterone is added to the estrogen doses because it reduces the risk of cancer of the uterus, a major concern with ERT in the past. The hormones estrogen and progesterone can be taken as tablets. They are also available in the forms of creams, skin patches, vaginal suppositories, and shots.
When is it used?
Estrogen replacement therapy can be used to treat some women before, during, and after menopause. Menopause means having no menstrual periods for at least 6 months to 1 year.
Estrogen replacement therapy is often recommended to relieve these symptoms associated with menopause:
- severe hot flashes
- vaginal dryness, resulting in discomfort or pain during sexual intercourse.
In addition, a doctor may prescribe estrogen therapy if you are at risk for osteoporosis or coronary heart disease.
The long-term effects of ERT, especially of combination therapy, are not yet fully known. Most studies have focused on the use of estrogen alone, and different studies have produced conflicting results. Therefore, it is important for you to talk with your health care provider about the potential benefits and risks of therapy so you can make an informed decision about whether to begin ERT.
What are the benefits of ERT?
- Prevention and treatment of osteoporosis
- Osteoporosis is a skeletal disorder that reduces the density of bone, thus making you prone to fractures. Estrogen therapy is the best prevention and treatment of osteoporosis. Calcium supplements can also help to cut down on bone loss.
- Reduction of the risk of coronary heart disease
- The risk of heart disease dramatically increases for women who have gone through menopause. Evidence shows estrogen reduces the risk of coronary heart disease.
- Relief of menopausal symptoms
Estrogen replacement therapy is also prescribed to relieve these symptoms of menopause:
- hot flushes or flashes, which may last for several months to a few years and are accompanied by profuse sweating
- sleep disturbances
- atrophic vaginitis, an irritation of the vagina, caused by loss of estrogen (less estrogen in the body causes the tissues of the vagina to shrink and become thin and drier).
What are the risks of ERT?
- Endometrial cancer
- Constant exposure of the endometrium (the lining of the uterus) to estrogen without progesterone is associated with a higher risk of endometrial cancer. High doses of estrogen and treatment for a long time increase the risk. To lessen the risk, doctors may prescribe lower doses of estrogen combined with progesterone.
- Breast cancer
- Studies are still being done to determine if being on ERT increases your risk of getting breast cancer. It is best to talk to your doctor about this possible risk. Many doctors recommend that women be checked thoroughly for any tumors and have a mammogram before beginning ERT. They also advise women taking ERT to have yearly mammograms and physical exams and to examine their own breasts monthly. If you have a family history of estrogen-dependent breast cancer, discuss this with your doctor.
What are the side effects of estrogen?
The side effects of estrogen may include:
- uterine bleeding and vaginal discharge
- bloating, fluid retention, and weight gain
- breast tenderness and enlargement
- symptoms resembling those of premenstrual tension, such as headaches and mood swings
- increased risk of gallstones if estrogen is taken orally.
What are the side effects of combination therapy?
Use of combination estrogen-progesterone therapy after menopause can cause vaginal bleeding. When you stop estrogen and progesterone combination therapy, or during the days in the cycle when you are not taking hormones, you will usually have some bleeding. Not a menstrual period, the bleeding typically lasts 2 or 3 days and is not usually accompanied by cramps or bloating.
Who should not take ERT?
If you have any of the following conditions or diseases, you should not take ERT:
- unexplained vaginal bleeding
- liver disease
- history of blood clots or strokes (thromboembolic disease); however, transdermal estrogen (a skin patch) may decrease thromboembolic disease
- endometrial or breast cancer.
If you have any of the following diseases or conditions, you may want to avoid ERT:
- uterine fibroids (These benign tumors grow in response to estrogen. They begin to shrink at menopause unless a woman takes estrogen. Taking progesterone with estrogen does not prevent the growth of uterine fibroids.)
- fibrocystic breast disease
- migraine headaches
- gallbladder disease.
If you smoke, you need to discuss this with your doctor before starting ERT.