Emergency contraception, otherwise known as post-coital contraception, is part of the continuum of contraceptive methods that women and couples can use for pregnancy prevention. Although emergency contraception should not be used as a regular, plan-ahead contraceptive method, it gives a woman one last-ditch effort to prevent unwanted pregnancy. This paper reviews the history of emergency contraception, the need for further studies, and results of studies conducted at the World Health Organization. Various methods used for emergency contraception are discussed, as well as their efficacies and side effects.