The researchers said they could not explain why hormone use should be associated with some types of cancers and not others.

The findings come at a time when hormone use is sharply declining.

More definitive results will come in 2005, when results from the first large-scale, long-term study of hormone use become available.

In the last few years, the advice to women has changed, and hormone use has dropped sharply, by more than 50 percent since 2002.

The effect of hormone use on the growth of prostate cancer is being studied.

However, hormone use may increase the risk of breast cancer, heart disease, and blood clots.

This risk appears to be highest in the first year of hormone use and declines greatly thereafter.

Also, once hormone use is stopped, the risk declines to that of nonusers.

Surprisingly, having a family history of breast cancer did not affect the mortality risk associated with hormone use.

But they asked only once about hormone use, which would not account for women who stopped its use.