Spermatic and peripheral venous plasma concentrations of progesterone, 17 alpha-hydroxyprogesterone, and 20 alpha-dihydroprogesterone in prepubertal boys.

Testosterone, progesterone, 17 alpha-hydroxyprogesterone, and 20 alpha-dihydroprogesterone have been measured in the spermatic and peripheral venous blood of 17 prepubertal boys undergoing surgery for undescended testis or inguinal hernia repair. Mean (+/-SE) spermatic testosterone and progesterone (538 +/- 212 and 704 +/- 110 pg/ml, respectively) were significantly higher (P less than 0.005) than peripheral levels (91 +/- 11 and 419 +/- 71 pg/ml, respectively). No significant spermatic-peripheral gradient was found for 17 alpha-hydroxyprogesterone and 20 alpha-dihydroprogesterone. These in vivo studies demonstrate that the secretory pattern of the prepubertal testis is different from the adult testis.