The influence of human chorionic gonadotrophin (hCG) on the morphology of the prepubertal human undescended testis.

The effect of hCG-treatment on the morphology of the undescended testis was studied in testicular biopsies from 36 prepubertal boys operated on at intervals of 1 day to 2 years after discontinuation of hormonal treatment. Immediately after treatment, mature Leydig cells were observed, and the Sertoli cells were increased in size; serum testosterone had increased to adult levels. All these changes were reversible as judged from the material taken one month or more after the last hCG injection. Based on the observations and the results of a previous study it is suggested that hCG treatment does not induce any premature onset of Sertoli cell or germ cell maturation either in the undescended or in the contralateral testis.