Estrogen: Friend or Foe?

September 3, 2003

By Tari Roche, DO


The hormone controversy is being hotly debated in the news. Most women used to be offered estrogen therapy at menopause, unless their medical history clearly indicated they should not. But there are now fears associated with estrogen therapy. These fears range from breast cancer to heart attack and stroke. How can you decide if estrogen and other hormone therapies are right for you?

Estrogen is a hormone naturally produced by the ovaries of a woman when she is having normal menstrual cycles. It causes the uterine lining to grow and breast tissue to enlarge. Estrogen exists in a delicate balance with progesterone. Progesterone is normally secreted once ovulation has occurred. This hormone causes the uterine lining to stop growing and slough off, resulting in a menstrual flow. In various combinations, estrogen and progesterone can be used to correct irregularities in the menstrual cycle and for birth control.

At menopause, the ovaries stop producing estrogen. When this occurs, ovulation stops and progesterone production tapers off. Menopause can also occur when the ovaries are removed or their blood supply is interrupted. The effects of menopause are many and vary for each woman. These include hot flashes, weight changes, moodiness, vaginal dryness, loss of interest in sexual activity, and urinary incontinence problems. Other changes occur that might not be readily apparent. These include loss of bone mass leading to osteoporosis, changes in fat metabolism, and impaired memory function. All of these symptoms and effects on your body can play an important part in your personal decision about hormone replacement therapy.

How Do You Decide?

For some women the choice is clear. Estrogen therapy should be avoided if you have a history of breast cancer or any type of estrogen-sensitive tumor (i.e. uterine or ovarian cancers.) Also, as a rule, you should avoid using estrogen if you have a history of blood clotting disorders. This includes any history of deep venous thrombosis, pulmonary embolism, or stroke.

If you experience hot flashes or vaginal dryness, hormone therapy should be considered. It will work better than other available therapies to stop these symptoms of menopause.

Intense controversy exists over using estrogen therapy if you have a history of cardiac disease. We used to believe estrogen might help lower the incidence of cardiac disease, because it seems to have a positive effect on lipid profiles. However, recent studies have shown this does not translate into a lower rate of heart disease. In fact, to the contrary, recent studies have indicated that the risks of cardiovascular disease are actually greater in women who have been treated with certain drugs containing estrogen and progesterone. In July 2002, a highly publicized study decided to halt part of the study because the overall risk of heart disease and invasive breast cancer appeared to outweigh the benefits of hormone treatment. The FDA stepped in to require labeling, with new safety information, on products containing estrogen and progesterone.

I recently attended a conference on this topic. A few points were stressed to prescribing doctors about hormone therapy:
1) Hormone therapy does not lower the incidence of heart disease and in fact may increase it. This is particularly true if a woman has not been exposed to hormones for some time and then is placed on HRT.
2) Estrogen does increase the growth rate of estrogen sensitive breast tumors, and seems likely to increase the overall incidence of breast cancer in women who have been on it for more than five years.
3) The best policy for prescribing hormone therapy appears to be using the lowest possible dose for the shortest possible amount of time needed to alleviate the symptoms.

What Other Choices Do You Have?

Alternative therapies you may want to consider include soy and herbal products, black cohash, and treatments such as clonidine and certain antidepressants for hot flashes. Also, osteoporosis may be prevented in many individuals by taking calcium and vitamin D supplements, getting regular weight-bearing exercise, and stopping smoking. Also, there are drugs available that do not contain hormones if bone density tests show your bones are thinning.

What Can You Do Today?

Remember, regular screening for cardiovascular disease and breast and other gynecological cancers is still the most important defense against heart attack and cancer death in women. In addition, you should
1) Keep your cholesterol down
2) Get regular exercise
3) Do not smoke
4) Stay up to date on pap smears and mammograms.
Talk to your health care provider about whether estrogen replacement is right for you. This is now, more than ever, a very personal decision.