What are the benefits of taking hormone therapy (HT)?
HT is prescribed to relieve:
- Hot flashes
- Vaginal dryness that can result in painful intercourse
- Other problematic symptoms of menopause, such as night sweats and dry, itchy skin
Other benefits of taking HT include:
- Reduced risk of developing osteoporosis and reduced risk of bone breakage
- Improvement of mood and overall sense of mental well-being in some women
- Decreased tooth loss
- Lowered risk of colon cancer
- Lowered risk of diabetes
- Modest improvement in joint pains
- Lower death rate for women who take hormone therapy in their 50s.
What are the risks of taking hormone therapy (HT)?
While HT helps many women get through menopause, the treatment (like any prescription or even non-prescription medicines) is not risk-free. Known health risks include:
- An increased risk of endometrial cancer (only if a woman still has her uterus and is not taking a progestin along with estrogen) .
- Increased risk of blood clots and stroke. However, in women within 5 years of menopause there was no statistically significant increase in stroke risk. Also, studies suggest that using estrogen delivered from the skin via a patch/cream might further lessen the risk of blood clots.
- Increased chance of gallbladder/gallstone problems.
- Increased risk of dementia if hormone therapy is started after a woman has been in menopause for 10 years. It is not yet known if it might be beneficial for women who start HT in their 50s.
Most of our understanding about the benefits and risks of hormone therapy on the heart and breast come from the Women’s Health Initiative (WHI) study (one of the largest studies done on hormone therapy):
HT and the heart
Recent analysis of WHI actually shows that the risk of heart disease may be related more to the advanced age of the participants as opposed to the HT. The study also found that HT given to younger women, at the onset of menopause, appeared to lower the risk of heart disease. More specifically:
An increased risk of heart disease is only seen in women taking long-term estrogen-progestin combination therapy (EPT) if they start HT in their mid-60s (or after 10 years from menopause). There does not seem to be an increased risk of heart disease when women start EPT in their 50s (or within 10 years of menopause). Estrogen alone (ET) has not been shown to increase the risk of heart disease. Analysis of the age since menopause actually shows a lower risk of heart disease when ET was started in younger women (those just beginning menopause).
Currently, it is not recommended to use hormone therapy solely for the purpose of preventing heart disease. However these studies give us reassurance that when women just newly approaching menopause need HT for a short time, it is safe to do so in terms of long term heart disease risk.
HT and breast cancer
Diagnosis of breast cancer increases when combination EPT is used beyond 3-5 years. This means that out of 10,000 women who use estrogen progestin therapy for more than 5 years, there will be 8 additional breast cancers diagnosed. In contrast, the WHI study showed women who use estrogen alone had no increase in risk of breast cancer even after 11 years of use. In fact, fewer breast cancers were seen in the group taking estrogen alone, though this was not statistically significant. When a woman comes off of hormone therapy, any potential increase in her risk of breast cancer quickly goes back to her baseline norm. This is why hormone therapy can be a safe option when women in their 50s (who are generally at lower risk for breast cancer compared to older women).
Does starting hormone therapy (HT) closer to the time of menopause make it safer?
One of the problems with the WHI study, which gave us much of our knowledge on the risks of HT, is that most women in the study were starting hormones in their mid-60s. Typically, women who need HT are newly menopausal, in their early 50s. Younger women in the WHI study had fewer risks and more benefits from HT. Newer studies are trying to understand the risks and benefits of HT in women in their 50s. One such study showed HT started early in postmenopausal women significantly reduced death rate, heart attacks and heart failure. These postmenopausal women who started HT early and used it for more than 10 years were not at increased risk of breast cancer or stroke.
Who shouldn't take hormone therapy (HT)?
HT is not usually recommended for women who have:
- Active or past breast cancer
- Recurrent or active endometrial cancer
- Abnormal vaginal bleeding that has not been evaluated
- Recurrent or active blood clots
- History of stroke
- Known or suspected pregnancy
What are the side effects of hormone therapy (HT)?
Like almost all medications, hormone therapy has side effects. The most common side effects are:
- Monthly bleeding (if progestin given cyclical)
- Irregular spotting
- Breast tenderness
Less common side effects of hormone therapy include:
- Fluid retention
- Headaches (including migraine)
- Skin discoloration (brown or black spots)
- Increased breast density making mammogram interpretation more difficult
- Skin irritation under estrogen patch
How can I reduce these side effects?
Adjusting either the dosage or the form of the medication you are taking can often reduce side effects of HT. However, you should never make changes in your medication or stop taking it without first consulting your doctor.