(HealthDay News) — Recent use of the injectable contraceptive depo-medroxyprogesterone acetate (DMPA) for 12 months or longer may approximately double the risk of breast cancer in young women, according to a study published online Feb. 27 in Cancer Research.
To investigate the association between DMPA use and breast cancer risk, Christopher I. Li, M.D., Ph.D., from the Fred Hutchinson Cancer Research Center in Seattle, and colleagues conducted a population-based study among 1,028 women aged 20 to 44 years. Structured, in-person questionnaires were completed to obtain information on DMPA use and other relevant covariates.
The researchers observed a 2.2-fold increased risk of invasive breast cancer with recent DMPA use for 12 months or longer. There was little variation in the risk by tumor stage, size, hormone receptor expression, or histological subtype.
“Although breast cancer is rare among young women and the elevated risk of breast cancer associated with DMPA appears to dissipate after discontinuation of use, our findings emphasize the importance of identifying the potential risks associated with specific forms of contraceptives given the number of available alternatives,” the authors write.