%0 Journal Article %T Male Reproductive Endocrine Disorders. %A McCoskey M %A Vernon N %J Prim Care %V 51 %N 3 %D 2024 Sep %M 39067971 %F 2.186 %R 10.1016/j.pop.2024.04.003 %X The endocrine system intricately regulates male sexual development and health which influences masculinization, sexual libido, muscle mass, bone density, and overall vitality. Disorders in the hypothalamic-pituitary-gonadal axis can lead to hypogonadism, gynecomastia, sexual dysfunction, and infertility. Testosterone replacement therapy can be considered for symptomatic hypogonadism but poses risks for azoospermia and polycythemia, along with uncertain impact on cardiovascular disease. Gynecomastia results from a high estrogen-to-androgen ratio, mostly from either excess estrogen or decreased androgens. Sexual dysfunction is more commonly secondary to psychological or metabolic disorders; consider workups to rule out endocrine etiologies including hypogonadism if indicated.