Germ cell development in the descended and cryptorchid testis and the effects of hormonal manipulation.

Germ cell development is an active process in normal testes during the first 4 years after birth, with transformation of the neonatal gonocytes into adult dark spermatogonia and then primary spermatocytes. The hormonal regulation of these changes is not fully understood, with evidence both for and against a role for gonadotrophins and androgens. Early surgical intervention in infancy aims to prevent or reverse germ cell maldevelopment. Although hormonal treatment for maldescent has been shown to be ineffective, there is still controversy over whether it may be useful as an adjunct to surgery to stimulate germ cells. Current evidence suggests that hormonal therapy may not stimulate transformation of neonatal gonocytes but may trigger prepubertal mitosis of primary spermatocytes. Further studies are required to determine the role of hormone treatment on germ cell development.