Hypophyso-gonadal function in the cryptorchid child: differences between unilateral and bilateral cryptorchids.

In 22 normal boys, 33 unilateral and 14 bilateral cryptorchids, a gonadal function test (2000 IU of HCG im each day for three days and assays of plasma testosterone and plasma oestradiol-17beta before and after the HCG administration) as well as an LH-RH test were carried out. In 60% of the cases, both normal and cryptorchid boys, plasma oestradiol-17beta (both in basal conditions and after stimulus) were found to be less than the sensitivity (5 pg/ml) of the method, While the plasma testosterone was similar under basal conditions in the three groups of children, after HCG it was significantly lower than the mean value of the control group only in the bilateral cryptorchids. The testosterone levels, both under basal conditions and after stimulus, are correlated to bone age only in the normal boys and in the unilateral cryptorchids. There were no significant differences among the various groups for either LH and FSH both under basal conditions and after LH-RH. The LH curve area during the LH-RH test is in correlation with bone age only in the normal children.