Dictionary of Cancer Terms
View in Spanish: Plan B
Plan B
A form of the hormone progesterone that is made in the laboratory and used to prevent pregnancy. It is being studied in the prevention of ovarian and endometrial cancer, and in the treatment of other conditions. Plan B is a type of oral contraceptive. Also called L-norgestrel and levonorgestrel.
Source: National Cancer Institute Dictionary of Cancer Terms, available at www.cancer.gov/dictionary.