Levonorgestrel is a female hormones that prevents ovulation (the release of an egg from an ovary). This medication also causes changes in your cervical mucous and uterine lining, making it harder for sperm to reach the uterus and harder for a fertilized egg to attach to the uterus.

Levonorgestrel emergency contraceptive is used to prevent pregnancy after unprotected sex or failure of other forms of birth control (such as condom breakage, or missing 2 or more birth control pills).