Human chorionic gonadotropin, called hCG for short, is a hormone used by bodybuilders to improve results during anabolic-androgenic steroid use. The hormone is produced by the placenta of a pregnant female and is essential for healthy pregnancy in humans. Some bodybuilders who use steroids also use hCG at the end of the steroid dosing cycle to increase testosterone production. Another use for hCG is to take it, via injection, in conjunction with a very low-calorie diet. Male bodybuilders use hCG at the end of an anabolic-androgenic steroid cycle to prevent the breakdown of muscle tissue and to restore the testes to normal abilities. This often returns shrunken testes to their normal size. When used along with a very low-calorie diet, bodybuilders burn off that extra layer of fat over their muscles, giving them an extremely defined look. Females may also use hCG with a very low-calorie diet to burn off unwanted fat.