Sex Hormone Binding Globulin

Sex hormone-binding globulin (SHBG) is the protein responsible for blood transport. Reversibly, SHBG binds to sexual steroids. Although it does so with a much lower binding affinity than SHBG, albumin, which is present in much higher concentrations, can also bind sexual hormones. When androgen levels are normal but clinical symptoms seem to point to an excess of androgen, measurement of SHBG can be a useful sign of an excessive/chronic androgenic activity. When there is a suspicion of a reasonably high concentration of free androgen (such as testosterone), SHBG is a helpful supplemental parameter in the androgen determination process.