Heterogeneity of the pituitary reserve of gonadotropins in children with cryptorchism

The Gn-RH test was applied to determine the hypophyseal reserve of gonadotropins in 67 prepuberal children with mono- or bilateral cryptorchidism and in 12 normal children of matching ages. On the basis of the gonadotropin response, 3 groups of cryptorchidism could be distinguished; those with a response similar to the normal controls (normal responders), those with an increased response (hyper responders) and a third, statistically less homogeneous group with insufficient response (hyporesponders). The findings were in agreement with earlier papers that emphasize the considerable variability of the hypophyseal gonadotropin reserve in cryptorchic children before puberty. The assumption is justified that in the hyporesponders, the incomplete descent of the testicles is due to a partial deficiency of gonadotropins while in the hyper responders, there is an early abnormality of hypothalamo hypophyseo gonadal feedback (analogous to that which is clearly demonstrable in adults operated on in childhood for cryptorchidism).