1. What is hormone replacement therapy ?

Hormone replacement therapy, often called HRT, is the use of estrogen combined with progesterone, or prosestin, the synthetic version. The drugs replace the hormones a woman's body largely stops making after menopause. The progesterone is taken as a safeguard against uterine cancer. Without it, the endometrium, or uterine lining, can build up excess tissue – a possible sign of cancer.

The new Postmenopausal Estrogen / Progesyin Interventions study - called PEPI - found that a third of the women who took estrogen alone had this type of buildup, a condition called endomemal hyperplasia.

2. What is estrogen replacement therapy?

It's the use of estrogen alone. The only women who should do that are those who have had a hysterectomy and no longer have a uterus, or are willing to have annual uterine biopsies.

3. Why do women take hormones?

Short-term, women may take hormones to relieve menopause symptoms, such as hot flashes and night sweats. Long-term, hormone replacement lowers a woman's chance of developing heart disease by at least 25 percent, depending on the drug combination she takes, and cuts her risk of the brittle bone disease, osteoporosis, by almost two-thirds.

But to get that benefit, a woman has to take hormones for most of her lifetime after menopause. The benefits stop when the drugs do.

4. Who are the best candidates for hormone replacement?

Women with extreme menopause symptoms; women with a family risk of heart disease or osteoporosis: and younger women who have had a hysterectomy in which their ovaries were also removed. The more years with reduced estrogen, the greater a woman's risk of osteoporosis and heart disease. So health, menopause and HRT are fairly closely linked.

5. Can blood tests help tell if you might benefit from HRT?

Opinions vary greatly. Many experts consider these tests unnecessary. But they may be helpful if menopause symptoms are intolerable but you're still having menstrual periods. Then, a blood test helps tell how much estrogen the body is making.