An examination of blood steroid and gonadotropin concentrations in relation to fertility status and testicular function in men.

Plasma concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), testosterone (T), and 17 beta-estradiol (E2) have been measured in men complaining of infertility in comparison with men of proven fertility. Subgrouping of patients was achieved on the basis of the presence or absence of sperm in the ejaculate and further by the concentration of sperm or by testicular score. The levels of plasma LH, FSH, PRL, and T were found to be significantly different in the fertile men, compared with both infertile men with sperm in their ejaculates and azoospermic men. There were no significant differences between the groups for E2. There appeared to be an inverse relationship between LH concentrations and sperm count in both fertile and infertile men. FSH levels did not vary significantly in the fertile men in relation to sperm count grouping but were significantly less than those found for the infertile men with sperm. Azoospermic patients with high testicular scores had FSH levels indistinguishable from those of the fertile men. The results are discussed in terms of testicular abnormalities and on the interrelationship between the hormones examined.