The aim of the study was to evaluate the hormonal pattern in men with idiopathic oligozoospermia and azoospermia. Material consisted of 13 sterile men, 21-34 years old (the mean - 27 years). Three of 13 patients had the third degree oligozoospermia, 3 - extreme oligozoospermia and 7 - azoospermia. The control group consisted of 11 healthy men who were found to have normozoospermia. In all patients and in control subjects the estimation of LH, FSH, prolactin (PRL), testosterone and dihydrotestosterone (DHT) in basal conditions and also PRL determination at 15, 30, 60 min after stimulation with metoclopramide (MCP 10 mg i.v.) were performed by radioimmunoassay. The results indicate that men with idiopathic oligo- or azoospermia have significantly higher prolactin level in response to dopaminergic receptor blockade with metoclopramide and significantly lower serum testosterone and DHT concentrations.