R. A. Elton

Immunocompetent cells in human testis in health and disease

The authors have investigated lymphocyte subpopulations and macrophages in normal human testes and the testes of patients under investigation and treatment for subfertility. Specific monoclonal antibodies were used in an indirect immunoperoxidase technique. In normal tissues, T lymphocytes (Leu 4-positive cells) were present in the rete testis with a preponderance of cells of the suppressor/cytotoxic phenotype. In contrast, no lymphocytes were detected within the peripheral portions of the testis. Cells reacting with the anti-Leu M3 monoclonal antibody, which defines monocytes/macrophages, were detected in appreciable numbers in peripheral testis with a specific location around the seminiferous tubules. HLA-DR-positive cells (human leukocyte antigens--class II [DR] determinants of the major histocompatibility complex) also were identified and showed a similar pattern of distribution to that of the Leu-M3 positive cells. While no lymphocytes were seen in the normal peripheral testis, T lymphocytes were detected in testicular biopsies from subfertile patients. Suppressor/cytotoxic T cells (Leu 2a-positive) predominated in patients with oligozoospermia and obstructive azoospermia while T cells of the helper/inducer phenotype predominated in patients with unilateral testicular obstruction and in postvasectomy patients. Sperm antibody measurements correlated with these findings.

Searching for the infertile man with hyperprolactinemia

The purpose of this study was to determine whether routine prolactin measurement was of use when investigating men with infertility. Prolactin levels were slightly higher in men with primary infertility, compared with men with secondary infertility and a fertile control group. Although this slight increase was statistically significant, most readings were within the laboratory normal range in all groups, and we did not find any clinically significant cases of hyperprolactinemia. We conclude that routine prolactin estimation is not justified unless there are other indications, e.g., impotence, dialysis, or a history of previous pituitary disease.

Estradiol and male fertility

Serum estradiol (E2) levels were measured in 451 men attending an infertility clinic and 80 fertile men attending for vasectomy. The normal range of E2 levels found in fertile men was 70 to 200 pmol/l. Subfertile men had lower mean E2 levels than fertile men (P less than 0.05), but there was no relationship to obesity, cigarette smoking, age, or the male infertility diagnostic category. E2 levels in the subfertile group gave no prognostic information concerning future fertility. The authors conclude that E2 measurements in male patients are not useful in clinical infertility practice.

Duration of involuntary infertility and subsequent pregnancy

During 1978-1983, 1,040 couples had been evaluated at our infertility clinic and subsequently followed up for an average of two years. The length of time the couple had been trying for a pregnancy (trying time) is shown to be strongly related to the subsequent chances of pregnancy. There are few effective treatments for male infertility and, therefore, these data may represent the spontaneous fertility rates from an untreated population. This background pregnancy rate should be useful to any physician planning a trial of treatment for the infertile couple when pregnancy is the success criterion, and allowance needs to be made for this spontaneous pregnancy rate when analyzing the results of treatments. Review of the literature suggests that some reported results could be misleading because of failure to allow for this background pregnancy rate.