The number of spermatogonia in various congenital testicular disorders.

Various congenital testicular disorders, including monorchism, retractile testis, cryptorchidism and male intersex, were investigated by counting the number of spermatogonia per seminiferous tubule. The results showed that all 7 cases of monorchism had normal numbers of spermatogonia per seminiferous tubule. However, in 29 cases of a retractile testis a normal testis was observed in 13 (44.8 per cent). Therefore testicular dysgenesis is suggested to exist in more than half of cases of the retractile testis. Of 150 cases of cryptorchidism 82 were bilateral and 68 were unilateral. There was no significant difference in the number of spermatogonia per seminiferous tubule between these 2 groups. The higher the testes were located the worse the ratio of spermatogonia per seminiferous tubule. Fewer or absent spermatogonia were observed in 2 patients less than 2 years old. Of 28 contralateral scrotal testes in patients with unilateral cryptorchidism 4 (14.3 per cent) had no spermatogonia per seminiferous tubule and 8 (28.0 per cent) had a decreased number of spermatogonia per seminiferous tubule. The male intersex patients had much damage even in the scrotal testes. From these results it is suggested that these congenital testicular disorders, except monorchism, have similar histological features. Moreover, these conditions are possibly related in etiology to the phenomenon of deficient androgen stimulation.