Five intratesticular sex steroids (testosterone, dihydrotestosterone, androstenedione, estradiol and epitestosterone) along with six serum hormones (LH, FSH, prolactin, SHBG, testosterone and estradiol) were determined in 84 non-obstructive azoospermic men, in order to evaluate to what extent serum and testicular tissue as well as individual hormones in the same material mutually correlate. With exception of androstenedione, tight correlations were found among tissue content of sex steroids, while only weak correlation was recorded between serum and testicular concentrations of major sex steroids testosterone and estradiol. It points to importance of measurement of intratesticular steroids in combination with examination of sperm parameters for assessment of testicular function and spermatogenesis., J. Heráček, V. Sobotka, L. Kolátorová, J. Kočárek, R. Hampl., and Obsahuje bibliografii