Depo Provera (medroxyprogesterone acetate) is a birth control product manufactured by Pfizer Inc. It is a hormonal birth control method for women in the form of an injection in the skin once every 11 to 13 weeks. Depo Provera causes the ovaries to stop producing eggs, preventing pregnancy (99.7% effective). A side effect (and to some a benefit) is that many women stop having a regular menstrual cycle while on the drug.

Depo Provera is also used with male sex offenders as a form of chemical castration as it has the effect of drastically reducing sex drive in males.