A breast implant is a prosthesis use to enlarge the size of a woman's breasts (known as breast augmentation, breast enlargement, mammoplasty enlargement, augmentation mammoplasty or the common slang term boob job) for cosmetic reasons; to reconstruct the breast (e.g. after a mastectomy; or to correct genetic deformities), or as an aspect of male-to-female sex reassignment surgery. According to the American Society of Plastic Surgeons, breast augmentation is the most commonly performed cosmetic surgical procedure in the United States. In 2006, 329,000 breast augmentation procedures were performed in the U.S.