How to determine the cause of male infertility.
D006801:Humans; D007248:Infertility, Male / Q000209:etiology*; D008297:Male; D009845:Oligospermia / Q000209:etiology; D012661:Semen / Q000032:analysis; D013091:Spermatogenesis; D014646:Varicocele / Q000150:complications