Sterilize an animal, also known as spaying or neutering, is a medical procedure that involves the removal of reproductive organs in order to prevent animals from reproducing. This procedure is often done to reduce pet overpopulation and to help control the spread of certain diseases. Spaying is the term used for female animals, while neutering is the term used for male animals. The procedure is usually done under general anesthesia and can be done at any age, although it is most commonly done when the animal is young.