Development of normal germ cells during childhood is a continuous process which ends at puberty. Cryptorchid gonads have severe impairment of their germ cell development which is more pronounced the higher the gonads are situated. However, all newborns with intra-abdominal testes had a normal number of germ cells. This strongly supports the theory that cryptorchidism is a disease and not a malformation. As a consequence, adequate and early treatment of cryptorchid boys should be undertaken in order to preserve good chances of fertility.