Results from a large national study may have put the nail in the coffin of hormone replacement therapy (HRT) treatments, the Associated Press reported Saturday.

The Women’s Health Initiative (WHI) study, a 15-year research program designed to address the most frequent causes of health problems and death in postmenopausal women, found that women taking estrogen and progestin pills for even a couple of years faced a greater risk of cancer, the AP reported from the San Antonio Breast Cancer Symposium. Wyeth’s Prempro, an estrogen/progestin combination drug, is still FDA approved for severe menopausal symptoms.

After going off the treatments, however, women can expect cancer and other risks to diminish quickly, returning to normal levels in roughly two years. The study’s leader, Rowan Chlebowski, told the AP that sharpens the previous message about HRTs: that they should only be used at the lowest doses and for the shortest amount of time possible.

Initial results from the study can be found at the WHI website. In a related story, Sen. Chuck Grassley requested documents relating to Wyeth’s publishing practices with regards to Prempro.