INDUCTION OF SPERMATOGENESIS WITH GONADOTROPINS IN CHINESE MEN WITH HYPOGONADOTROPIC HYPOGONADISM

The effects of gonadotrophin administration to 17 Chinese patients wit h hypogonadotrophic hypogonadism (HH) on testicular volume and inducti on of spermatogenesis were studied. Ten subjects had isolated HH and s even had hypopituitarism. Twelve of the subjects had prepubertal onset of HH and five of them had been treated previously with hCG for induc tion of puberty None had a history of cryptorchidism. During hCG treat ment for induction of spermatogenesis, all subjects had an increase in serum levels of testosterone into the normal adult male range and the ir testes increased in size from 3 (1-20) ml to 11.6 (5-20) ml [median (range), p<0.02]. Six subjects required treatment with hCG alone. Howe ver, the remaining 11 subjects, after at least 6 months treatment with hCG, required the addition of human menopausal gonadotrophin (hMG) to induce spermatogenesis. Two subjects remained azoospermic. One had a history of mumps orchitis and the other had isolated elevation of bloo d FSH levels, suggestive of primary testicular failure in addition to HH. Excluding one subject with fertile eunuch syndrome, the mean durat ion for first appearance of spermatozoa was 13 (4-52) months. Twelve s ubjects became fertile and pregnancy was achieved in their partners af ter 20 (4-78) months. The weekly doses for hCG and hMG were 4000 (3000 -10 000) IU and 225 (225-450) IU, respectively. Patients who responded to hCG alone had a significantly larger pretreatment testicular volum e, suggesting that they had only partial gonadotrophin deficiency. Pre pubertal onset of hypogonadism was not a determining factor for requir ement of hMG treatment. Pretreatment testicular volume correlated posi tively with the final testicular volume and negatively with the time t o achieve spermatogenesis, but not with the final sperm concentration. Previous use of hCG for induction of puberty with resultant testicula r growth, favoured a subsequent positive response to hCG. These subjec ts also required a lower dose of hCG for normalization of serum testos terone levels. In conclusion, gonadotrophins are very effective in sti mulating testicular growth and spermatogenesis in subjects with HH, an d the positive response to gonadotrophins can be determined by the pre treatment testicular volume.