RecruitingPhase 4Drug trialEtonogestrel (ENG) Implant Insertion for Emergency Contraception With Oral Levonorgestrel (LNG) vs PlaceboIntrauterine devices (IUDs) are highly effective to prevent pregnancy when used for emergency contraception (following unprotected intercourse in the last 3 days), but data are lacking for people who desire an etonogestrel (ENG) contraceptive implant in this situation. This proposal will identify the most effective way to start an implant for emergency contraception using a randomized controlled trial comparing pregnancy risk between those receiving the implant vs. the implant plus oral emergency contraception (EC). Data from this project will inform clinical practice and add another option, the implant, for those desiring a long acting, highly effective contraceptive method when they present for emergency contraception.