http://www.chron.com/disp/story.mpl/...z/3958806.html
.."while there is a blood test for HGH, '... because antibodies necessary for the process are in such short supply, virtually no HGH testing is conducted. In addition, the test only detects HGH right after injection so it's impractical for in-competition testing. As a result, there never has been an HGH positive.'"