Treatment of cryptorchidism by intramuscular administration of LHRH.

Ten prepubertal boys, aged 6-12 years, presenting with unilateral or bilateral cryptorchidism were treated with a single i.m. injection of 100 micrograms of synthetic LHRH. In addition to the clinical effect, pituitary responsiveness was studied. Immunoreactive FSH and LH in serum were measured by radioimmunoassay. One week after the treatment a complete descent of testes occurred in the four oldest patients. In another four patients, a clear-cut improvement in their condition was seen, and, in two patients, no effect was observed. In nine patients, a significant (p less than 0.001) rise in serum FSH and LH levels was observed. In one patient, serum gonadotropin levels remained unchanged. There was no correlation between the clinical effect and pituitary responsiveness. It was concluded that i.m. administration of LHRH offers advantages over the paranasal route since the dose required for a good effect appears to be considerably lower.