Postmenopausal women and their doctors are getting tired of trying to use "evidence-based medicine" to make decisions about hormone replacement therapy (HRT).

At first, I and other physicians enthusiastically embraced HRT when nearly 30 different studies found that estrogen reduced the likelihood of heart attacks. After adding in the relief of menopausal symptoms and protection against bone-weakening osteoporosis, HRT seemed like a no-brainer to me.

Then, in 2002 the first phase of the Women's Health Initiative (WHI), which was investigating an estrogen-progestin combination pill, was stopped because of a higher rate of heart attacks, breast cancer, and strokes. WHI's second phase, taking estrogen alone, was stopped in 2004 due to an increased risk of blood clots and strokes.

These results from two separate phases of the WHI, showing that hormone replacement in postmenopausal women increased their risk of heart attacks and strokes, jolted doctors and patients alike and led millions of women to stop taking any form of HRT after the menopause.

Now, however, it is apparent that we all gave up on HRT too soon. What threw us off was the fact that, on average, the subjects in the WHI study began taking HRT when they were about 18 years past the menopause. And now it's clear that these were the women with the increased risk of a heart attack.

One new analysis of the timing of HRT in the WHI study has led to the conclusion that it is safe for women to use HRT for relief of postmenopausal symptoms if started soon after the menopause and taken for only a few years.

It's not clear how long women should use HRT. Probably the best advice is to use the smallest possible dose for the shortest possible time to relieve menopausal symptoms.
 
The latest analysis of WHI results provides further evidence that taking estrogen early in the menopause does not raise the risk of coronary heart disease. This study involved coronary artery scans on more than 1,000 women who started taking estrogen in their 50s — that is, soon after the menopause.

These particular women did not require a progestin to protect against uterine cancer because their uterus had been removed. (About one-quarter of American women have had this operation.) After taking either estrogen or a placebo for an average of 7½ years, the women who took 80 percent of their daily estrogen dose had 61 percent less calcium in their coronary arteries than did those who were assigned to the placebo.

Even when started soon after the menopause, HRT does raise the risk of strokes and of blood clots in the leg veins. Still, the risk of a stroke is quite small because it is uncommon in these younger women.  

For the sake of all women and doctors, I hope this will be the last word on HRT in postmenopausal women — but I seriously doubt it.