Depo-Provera an Injectable Contraceptive Used by 1.2 million U.S. Women. Depo-Provera (depo-medroxyprogesterone acetate, or DMPA) an injectable contraceptive used by about 1.2 million U.S. women, may increase the risk of invasive breast cancer in young women. Depo-Provera is a progestin-only birth control method, and is made with the same type of progestin found in Prempro, a hormone replacement therapy medication that has been associated with breast cancer in post-menopausal women.
Few studies have been done to assess the potential of Depo-Provera to cause breast cancer in young women. However, some international studies have produced mixed findings. To add to knowledge about this possible risk, researchers at the Fred Hutchinson Cancer Center compared data on 1,028 Seattle-area women ages 20 to 44 who had been diagnosed with breast cancer to 919 age-matched controls who did not have a history of breast cancer. About 10 percent of subjects in the study reported using Depo-Provera.
Depo-Provera Increased Risk of Breast Cancer
Recent use of Depo-Provera (within five years) for 12 months or longer was associated with a 2.2-fold increased risk of invasive breast cancer, the study found. Women who used DMPA for less than a year or who had stopped using it more than a year earlier did not have an increased risk of breast cancer. The risk began to lessen in the months after a woman stopped using Depo Provera.
“While DMPA is widely used by women throughout the world, there are limited data on the association between DMPA and breast cancer incidence,” Christopher I. Li, M.D., PhD., a member of the Hutchinson Center’s Public Health Sciences Division, said in a press release. “Our study adds to the body of knowledge from international studies conducted in a diverse group of countries – Kenya, New Zealand, Thailand, Mexico and Costa Rica – which have shown that one of the risks associated with DMPA use may be an increased risk of breast cancer.”