Sex reassignment surgery involves a series of surgical procedures to change a person's appearance. The goal of sex reassignment surgery is for the male patient to appear female and the female patient to appear male. Patients who seek to have sex reassignment surgery are termed transsexual which refers to their changing sexual characteristics. The central surgery in all sex change operations is genitalia reassignment. The ideal patient for this type of surgery is in good health, does not smoke, and is not overweight. Health diseases like diabetes and problems like obesity may not prohibit a surgeon from performing sex change surgery but they will increase the risk of complications. If a patient is overweight his doctor will suggest he lose a certain number of pounds before surgery. Patients who test positive for HIV or hepatitis C will have a difficult time because few doctors are willing to perform this surgery on this type of patient.