The effectiveness of EC depends on the type used and the time elapsed since unprotected intercourse. - Levonorgestrel pills reduce the risk of pregnancy by 89% if taken within 72 hours. - Ulipristal Acetate is more effective, especially between 72 to 120 hours, and can reduce the risk by up to 85%. - Copper IUDs are the most effective form of EC, with a failure rate of less than 1%.
