TUESDAY, July 14 (HealthDay News) -- Women on hormone replacement therapy may have a significantly increased risk of ovarian cancer, according to a study published in the July 15 issue of the Journal of the American Medical Association.

Lina Steinrud Morch, of Copenhagen University in Denmark, and colleagues conducted a national prospective cohort study of 909,946 women ages 50 to 79 years without hormone-sensitive cancer or bilateral oophorectomy, 3,068 of whom developed ovarian cancer during an average of eight years of follow-up.

Compared to nonuse of hormone replacement therapy, the researchers found current use was associated with an increased risk for all ovarian cancers and epithelial ovarian cancer (incidence rate ratios, 1.38 and 1.44, respectively). They also found that the number of years since hormone replacement therapy cessation was associated with a decreasing risk of ovarian cancer, with incidence rate ratios ranging from 1.22 for a last use of zero to two years to 0.63 for a last use of more than six years.

"Our study suggests an increased risk of ovarian cancer with both estrogen therapy and combined hormone therapy, with little influence of different regimens, progestin types, routes of administration, length of use, and different doses," the authors conclude. "Thus, the risk of ovarian cancer is one of several factors to take into account when assessing the risks and benefits of hormone use."

One author reported financial relationships with the pharmaceutical industry.

Abstract
Full Text (subscription or payment may be required)