Serum insulin-like factor 3 quantification by LC–MS/MS in male patients with hypogonadotropic hypogonadism and Klinefelter syndrome

Insulin-like factor 3 (INSL3) is an emerging testicular marker, yet larger studies elucidating the clinical role of INSL3 in patients with hypogonadism are lacking. The aim was to describe serum INSL3 concentrations analyzed by LC–MS/MS methodology in males with hypogonadotropic hypogonadism (HH) and Klinefelter syndrome (KS).