Two injectable forms of hormonal contraception, depot medroxyprogesterone acetate (DMPA, Depo-Provera) and medroxyprogesterone acetate/estradiol cypionate (MPA/E2C, Lunelle), are now available to American women. Both formulations have demonstrated high degrees of efficacy, safety, and ease of use in international and U.S. trials. Data on DMPA have shown a number of noncontraceptive and therapeutic benefits, the most prominent of which is an 80% reduction in the risk of endometrial cancer. Although such benefits are less documented for MPA/E2C, they are expected to be similar to those seen with DMPA and oral contraceptives. Minor side effects of both formulations include menstrual irregularities in the early months of treatment and amenorrhea with DMPA. Patient counseling about the potential for these side effects, as well as possible risks, is important to long-term successful use of these contraceptive methods.