Free Androgen Index (FAI) LabCorp

This test measures the level of free testosterone in your blood, which is the testosterone that is not bound to proteins and is biologically active. It is often used to help diagnose conditions like Polycystic Ovary Syndrome (PCOS) in women or certain hormonal imbalances in men. The FAI combines the total testosterone level with the Sex Hormone Binding Globulin (SHBG) level to estimate the amount of free testosterone.