Depot-medroxyprogesterone acetate (DMPA) and risk of liver cancer. The WHO Collaborative Study of Neoplasia and Steroid Contraceptives.

A hospital-based case-control study was conducted to assess the possible relationship between use of depot-medroxyprogesterone acetate (DMPA), an injectable progestational contraceptive, and the development of liver cancer in 2 developing countries where hepatitis B is endemic. Information about prior DMPA use and potential confounders was ascertained during personal interviews with 71 cases and 530 controls from 3 hospitals in Thailand and 1 hospital in Kenya. No significant association between liver cancer and DMPA use was observed in Kenya (RR = 1.64, 95% Cl = 0.4-0.6) or Thailand (RR = 0.33, 95% Cl = 0.1-1.0). No consistent changes in risk were observed with duration of use, time since last use, or time since first use. No significant associations were observed between DMPA use and risks of either hepatocellular carcinoma or cholangiocarcinoma. These findings suggest that risk of liver cancer in areas where hepatitis B is endemic is not appreciably altered by the use of DMPA.