birth control shot,
The birth control shot, Depo-Provera, is a hormonal injection that prevents unplanned pregnancy for three months at a time. The hormone in this shot is progestin. The birth control shot works similarly to the birth control pill. It prevents ovulation and increases the mucus buildup around the opening of the cervix. According to Planned Parenthood, when you receive it as directed, the shot is 99 percent effective.