Also known as: SHBG, TeBG, Testosterone-binding Globulin.

Sex Hormone Binding Globulin (SHBG), a protein, is produced by the liver and binds tightly to dihydrotestosterone (DHT), testosterone, and estradiol (an estrogen) and transports them in the blood in a metabolically inactive form. The amount of SHBG in circulation is affected by sex and age, increased or decreased testosterone or estrogen production, and can also be affected by diseases and conditions such as liver disease, obesity, amd hyperthyroidism or hypothyroidism. SHBG and testosterone levels may be ordered on an adult male to help determine the cause of infertility, erectile dysfunction, and decreased sex drive, especially when total testosterone results are inconsistent with clinical signs.