The USA hCG Reference Service sometimes investigates professional sportsmen that have tested positive in an hCG test. Men take hCG to promote testosterone production. The testosterone can promote anabolism or muscle growth. Taking hCG or testosterone is illegal in all sports and professional games. It is considered unfair doping. Urine tests are performed by anti-doping agencies at all games and sports events. If a man is found to be positive for hCG he is accused of doping, and possibly banned from sports and games.
The USA hCG Reference Service has found that professional football players (NFL), soccer players and olympians have been found positive for hCG. Many players have denied taking hCG. Upon investigation 5 professional players and their families were found to have Familial hCG Syndrome. Other possibilities include non-trophoblastic cancer and testicular germ cell cancer. In two cases, the USA hCG Reference Service could only confirm the presence of regular hCG and the likelihood that players were doping.