Bilateral spontaneous descent of the testis after the age of 10: subsequent effects on fertility.

Fertility after late spontaneous descent of the testes in 45 men with previous bilateral undescended testes was evaluated on the basis of seminal analysis and concentrations of follicle-stimulating hormone (FSH) in serum. Only 15 (33 per cent) were found to have a normal fertility as estimated from the results of the total semen analysis, whereas 21 (47 per cent) were classified as being sterile or having severely reduced fertility. Elevated serum FSH concentrations in the majority of men with subnormal sperm densities supported the results of the semen analysis, indicating impaired spermatogenesis. These findings suggest that the expectant attitude in the treatment of cryptorchidism does not seem to be justified in terms of fertility and combined with recent histomorphological studies favour a more active and early treatment of undescended testes.