Exploration of the testis in infertile men. Relationships among serum levels of FSH, LH, 17-alpha-OH-progesterone and testosterone.

A considerable body of evidence is available indicating a paracrine relationship between the seminiferous tubules and the Leydig cells. In 113 adult subjects in basal conditions the blood levels were determined of FSH (follicle stimulating hormone), LH (luteinizing hormone), 17-alpha-OH-P (17-alpha-OH-progesterone) and T (testosterone) either as a whole or as a free fraction. According to the sperm counts and the FSH levels, the studied subjects were divided into three groups: a group N (Normozoospermia) with sperm counts greater than 20 million/ml and FSH levels of 2.5 +/- 1.5 (mean +/- SD, mIU/ml), a group MO (moderate oligozoospermia) with mild degree of oligozoospermia (5-10 mill) and FSH levels in the range found in group N, a group SO (severe oligozoospermia) with severe degree of oligozoospermia (sperm count less than 5 mill/ml) and FSH levels greater than 2 SD the mean value in the N. Serum levels of LH, 17-alpha-OHP, total T, free T and FSH/LH, LH/T, 17-alpha-OHP/T ratios in group MO and SO were compared with those found in the group N.(ABSTRACT TRUNCATED AT 250 WORDS)