NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,919 terms related to cancer and medicine.
- Plan B
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- 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.