Women's Health Initiative Study

The other major study was the Women' Health Initiative (WHI) study that started in 1997 in which 16,608 women aged 50 to 79 with an intact uterus were recruited by 40 clinical centers in the United States to participate in a study where half the women were randomly selected to receive Prempro, an estrogen plus progestin drug, and the other half received a placebo. It was the first randomized trial to determine whether estrogen plus progestin had an overall favorable or unfavorable effect on prevention of coronary heart disease in mostly healthy post-menopausal women (recall that the HERS/HERS II followed women with pre-existing coronary heart disease).

The trial was stopped in July of 2002 as experts monitoring the trials safety found an increased risk of breast cancer, coronary heart disease, stoke and pulmonary embolus in women taking the HRT and that these risks far outweighed the benefits of fracture prevention and possibly colon cancer.

To sum up the findings, women who received an estrogen-progestin HRT regime were found to have:

• 26% increase in invasive breast cancer
• 41% increase in strokes
• 29% increase in heart attacks
• 111% increase in venous thromboembolism (blood clots) in legs and lungs
• 37% decrease in colorectal cancer
• 34% decrease in hip fractures

As apposed to those that received a placebo.

For more information see: Press Release: Tuesday July 9, 2002; view it on JAMA' website.

This study plainly outlines the inherent risks with HRT.