Isolated follicle stimulating hormone deficiency

A rare congenital hypogonadotropic hypogonadism characterized by hypogonadism due to selective deficiency of follicle stimulating hormone (FSH). Clinical manifestations are primary amenorrhea, absent or incomplete breast development, and infertility in women, and small testes, azoospermia, and infertility in men. Luteinizing hormone is elevated in the gonadotropin-releasing hormone stimulation test, while the FSH response is impaired.