“…Although the gold standard of fertility studies in men is semen analysis, measurements of inhibin B and gonadotropins contribute to an indirect evaluation of fertility and are extremely useful in cases where sperm samples are not available, for example, for cultural or ethical reasons (21). Inhibin B also can be used as a direct marker of Sertoli cell function and spermatogenesis in adult males (22)(23)(24)(25). Serum inhibin B and FSH levels correlate well with sperm concentration and thus can play a role as serum markers of spermatogenesis (26).…”