AfterPill is after-sex birth control. When used quickly, it reduces the chance of becoming pregnant after unprotected sex or regular birth control failure. It contains 1.5mg of levonorgestrel, the same medicine as Plan B, the best-selling and #1 doctor-recommended medicine for emergency contraception. It is the same medicine that has been used safely and effectively in regular birth control pills for over 30 years. New AfterPill Emergency Contraceptive can be used effectively for up to 72 hours (3 days) after unprotected sex or birth control failure. It is more effective the sooner you use it, and it has been shown to be most effective when used within 12 hours following unprotected sex. If you are already pregnant, new AfterPill will not work. It will not terminate or harm an existing pregnancy. According to the World Health Organization, levonorgestrel works similarly to regular birth control pills by preventing ovulation or preventing fertilization. Like all birth control pills, new AfterPill does not protect against HIV/AIDS or other sexually transmitted diseases.