FDA has carefully reviewed data from the Women's Health Initiative (WHI) study to ensure that the labels of Prempro and similar estrogen, and estrogen with progestin, products are accurate.

FDA has revised the labeling of Prempro, Premphase and Premarin for patients and physicians to reflect the WHI study's findings of increased risk from these products.

For two uses, FDA has revised the professional and consumer labels to include consideration of alternative therapies that may provide benefits to postmenopausal women.

When these products are being prescribed solely for symptoms of vulvar and vaginal atrophy, the new label recommends that topical products be considered.

When these products are only used for osteoporosis prevention, the new label specifies that the risks for osteoporosis must outweigh the risk of estrogen or estrogen with progestin.

FDA is asking all manufacturers to update their labeling with the results of the WHI, because all estrogen and progestin products are believed to have similar risks

FDA will soon revise its formal guidances for industry in two related areas: labeling for all estrogen and estrogen with progestin products for postmenopausal women, and recommendations for conducting clinical trials to develop new products for postmenopausal women.

Estrogens provide valuable therapy for many women, but carry serious risks, and therefore postmenopausal women who use or are considering using estrogen or estrogen with progestin treatments should discuss with their physicians whether the benefits outweigh the risks.

For hot flashes and symptoms of vulvar and vaginal atrophy, these products are the most effective approved therapies.

Estrogens and progestins should be used at the lowest doses for the shortest duration to reach treatment goals, although it is not known at what dose there may be less risk of serious side effects.

The WHI study included 16,000 women ages 50 to 79, with a uterus, taking Prempro or a placebo.

In July 2002, one "arm" of the study was halted because it showed that the overall health risk (especially of cardiovascular disease and breast cancer) from taking estrogens with progestin was greater than the benefits of lowering the risk of colon cancer and bone fractures.

The study showed that, for every 10,000 women taking estrogen with progestin for one year, there may be seven more cases of heart disease, eight more strokes, eight more blood clots to the lungs (13 more in the limbs) and eight more cases of breast cancer - while there may be six fewer cases of colon cancer and five fewer hip fractures.

FDA will continue to engage the National Institutes of Health (which sponsored the WHI) as well as manufacturers in pursuing research on questions involving the safety and effectiveness of these products.