Prempro (conjugated estrogen/medroxyprogesterone acetate) is a drug used for relief from symptoms of menopause and osteoporosis. Manufactured by Wyeth-Ayerst Laboratories, Prempro was approved in 1995 by the US Food and Drug Administration (FDA).

Prempro is a combination of estrogen and progestin for the use of women who have not had hysterectomy and are going through menopause. It is the first of its kind used for hormone replacement therapy (HRT).

Health Issues Related to Prempro

In 1991, a long-term study related to prevention of heart disease, osteoporosis, breast cancer and colorectal cancer in women was started by the National Heart, Lung, and Blood Institute (NHLBI) as part of the Women’s Health Initiative (WHI). Clinical and observational studies were conducted on 161,000 women in postmenopausal stage.

A clinical study was conducted on 16,608 women who either took Prempro or a placebo to find out Prempro’s effectivity in preventing hip fractures and heart diseases in the subjects. This study was discontinued after five years because researchers have found that the drug has greater risks than benefits. While it has been found that Prempro helps prevent hip fractures and reduces the risk of colorectal cancer, women who took the drug were at more risk in getting a stroke, developing breast cancer, heart disease and blood clots. The women who took Prempro for the WHI study were healthy and did not have any history of heart diseases, that’s why the increase in the cases of heart attacks and stroke were more significant.

However, different drugs with the same estrogen/progestin combination have different formulations, which is why it is not clear if all the other similar drugs would have the same risks.

Wyeth’s action in relation to the WHI study included the issuance of supplemental Prempro labeling to include the results of the said study.

FDA Action

FDA approved the new labels for Prempro, which stated a warning on the drug’s possible side effect of increasing the risk for strokes, heart attacks, heart diseases and breast cancer. In addition to the results of the WHI’s  study, the new labels included a caution that Prempro is not to be used to prevent CHD; should be used the shortest amount of time possible for specific treatment goals; should be periodically reevaluated; and should be “carefully considered” for use only to prevent osteoporosis, or treat vaginal dryness and irritation, because alternative non-hormonal treatments carried less risk.

FDA ordered all other manufacturers of drugs with estrogen and estrogen-progestin to indicate similar warning to the product’s labels and patient information materials.

Getting Legal Help

Most medications have some side effects, some mild, while others are more serious. The manufacturer of such products have the duty to provide adequate information to the medical community and the public regarding the drug’s known risks. Should they not do so, the manufacturer may be held liable, under product liability theory,  for any injury or harm caused by their product.

If you or a loved one has taken Prempro and have experienced any negative side effects or injury, go to your health care provider as soon as possible. You may also want to consult with an experienced attorney who could give you more information regarding your rights, if you have a case against the manufacturer, and the steps you need to take in order to seek legal relief for your injuries.

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