An Investigation of Plasma Hormone Levels Before and After Vasectomy**Supported by Contract NO1-HD-2-2776 from the Center for Population Research, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Md.††Presented in part at the Thirty-First Annual Meeting of The American Fertility Society, April 3 to 5, 1975, Los Angeles, Calif

Survivin downregulation is associated with vasectomy-induced spermatogenic damage and apoptosis

OBJECTIVE

To evaluate the expression of the apoptotic genes survivin, Bax and Bcl-2 in vasectomized rabbits and to determine their relation with vasectomy-induced spermatogenic impairment and germ cell apoptosis.

MATERIALS AND METHODS

Twelve adult rabbits (6-12 months old) were divided into three groups: sham control, unilateral vasectomy or bilateral vasectomy. Six months after vasectomy, testicular tissue was analyzed for germ cell apoptosis and DNA fragmentation by the TUNEL assay and gel electrophoresis, respectively. Spermatogenesis was assessed using the Johnsen score. The relative gene expression of survivin, Bax and Bcl-2 was measured using reverse transcription followed by real-time PCR.

RESULTS

Compared to sham animals, a significant decrease in testicular survivin mRNA levels was measured in the two vasectomy animal groups (p < 0.05). This was accompanied by a significant increase in the Bax:Bcl-2 ratio in the vasectomized animals (p < 0.05). In addition, these data showed positive correlation with enhanced apoptotic index, damage to spermatogenesis and DNA fragmentation after vasectomy.

CONCLUSION

These findings demonstrate that vasectomy-induced damage to spermatogenesis due to testicular apoptosis may be associated with survivin downregulation and Bax overexpression.

Effects of vasectomy on spermatogenesis and fertility outcome after testicular sperm extraction combined with ICSI

BACKGROUND

Each year 40,000 men have a vasectomy in the UK whilst another 2400 request a reversal to begin a second family. Sperm can now be obtained by testicular biopsy and subsequently used in assisted conception with ICSI. The study aims were to compare sperm yields of men post-vasectomy or with obstructive azoospermia (OA) of unknown aetiology with yields of fertile men and to assess any alteration in the clinical pregnancy rates after ICSI.

METHODS

Testicular tissue was obtained by Trucut needle from men who had undergone a vasectomy >5 years previously or had OA from other causes and from fertile men during vasectomy. Seminiferous tubules were milked to measure sperm yields. Numbers of Sertoli cells and spermatids and thickness of the seminiferous tubule walls were assessed using quantitative computerized analysis.

RESULTS AND CONCLUSIONS

Sperm yields/g testis were significantly decreased in men post-vasectomy and in men with OA, relative to fertile men. Significant reductions were also observed in early (40%) and mature (29%) spermatid numbers and an increase of 31% was seen in the seminiferous tubule wall (basal membrane and collagen thickness) of vasectomized men compared with fertile men. Clinical pregnancy rates in couples who had had a vasectomy were also significantly reduced.

Possible biological mechanisms for a relationship between vasectomy and prostatic cancer

Four hypotheses have been reviewed, each of which might serve as a hypothetical biological explanation for a relationship between vasectomy and prostate cancer. The endocrine hypothesis is the only one of these with any firm data to support it, although the majority of the available data does not lend credibility to that theory. The other hypotheses are purely speculative with no hard data to support them. In conclusion, it seems highly unlikely, but not impossible, that there is a biological mechanism supporting a relationship between vasectomy and prostate cancer.

Does vasectomy have long-term effects on somatic and psychological health status?

All the major international articles on the somatic and psychological consequences of vasectomy published over the last 10 years have been reviewed and analysed. Although some experiments on animals have revealed harmful effects, none of the large-scale epidemiological studies has pointed to any increase in health risks (cardiovascular, hypertensive, psychiatric) in vasectomized men. The contradictions which arise between the clinical and large-scale epidemiological studies may be the result of methodological or experimental conditions. As our knowledge stands at present it can therefore be considered that vasectomy has no major effects on the physical or mental health of men.

The effect of vasectomy on the production of plasma luteinizing hormone and follicle stimulating hormone in man

A prospective study of plasma luteinizing hormone (LH) and follicle stimulating hormone (FSH) in 51 men before vasectomy and 10 days and 3 months after vasectomy revealed a trend to rise in LH 10 days after vasectomy normalizing after 3 months. The literature concerning alterations in LH and FSH after vasectomy is reviewed and different theories are discussed.

Detection of testicular endocrine abnormalities and their correlation with serum antisperm antibodies in men following vasectomy

We measured the serum gonadotropin response to gonadotropin-releasing hormone in 25 men who underwent vasectomy 2 to 64 months before the study. Ten age-matched fertile men were used as controls. Baseline serum follicle-stimulating hormone, luteinizing hormone and testosterone levels were not significantly different between vasectomized men and controls. However, mean serum follicle-stimulating and luteinizing hormone responses to an intravenous bolus injection of 100 mcg. gonadotropin-releasing hormone were significantly greater in the vasectomy group (p equals 0.008 and 0.003, respectively). There was no correlation between these responses and the interval after vasectomy. Serum antisperm antibodies were present in 13 vasectomized men (52 per cent) using enzyme-linked immunosorbent assay and microagglutination techniques. A significant correlation (p equals 0.003) was found between the presence of serum antisperm antibodies and a normal follicle-stimulating hormone response to gonadotropin-releasing hormone stimulation. Of 13 patients with demonstrable antisperm antibody titers 9 (69 per cent) had normal follicle-stimulating hormone responses, compared to only 1 of 12 (8 per cent) without identifiable antisperm antibody titers. Our data suggest that certain men following vasectomy have abnormalities in seminiferous tubule and Leydig cell functions of the testes. These abnormalities are unrelated to the interval after vasectomy and are not identifiable with routine static hormonal measurements. In addition, serum antisperm antibodies are most likely to be present in men who demonstrate normal seminiferous tubular activity after vasectomy.

Annual variation in semen characteristics and plasma hormone levels in men undergoing vasectomy

Prevasectomy levels of plasma luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T), estradiol (E2), and 20 alpha-dihydroprogesterone (20 alpha-DHP), as well as semen analyses including semen volume, sperm count, and sperm motility from 260 healthy men were evaluated for annual changes. A statistically significant (P less than or equal to 0.015) high-amplitude seasonal variation with the peak in April to May was detected in semen volume, sperm count, and sperm motility. A statistically significant (P less than or equal to 0.04) annual change of moderate T to large FSH amplitude was detected in each of the five plasma endocrine variables as well. Plasma LH, T, and E2 peaked in autumn, while FSH and 20 alpha-DHP peaked in summer. Analysis of postvasectomy LH, FSH, E2, 20 alpha-DHP, and T blood levels for the 3 years following vasectomy revealed loss of seasonal rhythmicity as a group phenomenon in LH, E2, and T. The amplitude of the seasonal variation in FSH was decreased and that in 20 alpha-DHP was unchanged compared with before-vasectomy baselines. For those annual rhythms which persisted following vasectomy, the peak time was unchanged. Compared with the prevasectomy group annual mean, that for each of the endocrine values was unchanged, except for that of LH and T, which was slightly, yet statistically significantly, elevated. The existence of prominent annual variation implicates their consideration in the design of research protocols involving investigation of reproductive phenomena in human beings.

A late post-vasectomy syndrome

A group of 20 surgical specimens in 18 patients with a previously unappreciated syndrome of unremitting epididymal pain and induration 5 to 7 years after vasectomy was collected during a 2-year interval. These symptoms uniformly were unresponsive to conservative measures, including empiric antibiotics. Total unilateral or bilateral epididymectomy and partial vasectomy led to complete relief of symptoms, usually within 24 hours. Pathological examination of the specimens revealed features consistent with sequelae of long-standing obstruction. Recognition of this late post-vasectomy syndrome, which represents a major complication of vasectomy, might be expected to increase as cohorts of vasectomized individuals age.

Influence of vasectomy on the volume of the non-hyperplastic prostate in men

The influence of vasectomy on the volume of the non-hyperplastic prostate was investigated in 24 men referred consecutively for vasectomy. A comparison of trans-rectal prostatic volume determined ultrasonically before vasectomy and three months post-operatively revealed a highly significant decrease (P less than 0.01) in the volume of the peri-urethral portion of the gland. The volume of the outer zone of the prostate did not change significantly (P greater than 0.1). This may indicate that the prostate is not a functionally homogenous organ. It is postulated that there may be a local influence on the prostate via a hormone transported in the deferent duct and/or the deferential vein.

Enhanced follicular recruitment in an in vitro fertilization program: clomiphene alone versus a clomiphene/human menopausal gonadotropin combination

In an attempt to improve the pregnancy rate following in vitro fertilization and embryo transfer by increasing the numbers of embryos available for transfer to each patient, a prospective, randomized comparison of clomiphene citrate alone (50 mg/day, cycle days 5 to 9) with the combination of clomiphene as above plus human menopausal gonadotropin (2 ampules/day, cycle days 6, 8, and 10) was undertaken from January through April 1983, with 17 patients in each group. The combination produced increased follicular development, compared with clomiphene alone, resulting in the retrieval of more fertilizable oocytes. Two clinical pregnancies resulted in each group. These results show that a fixed combination of clomiphene and human menopausal gonadotropin produces a greater degree of enhanced follicular recruitment, resulting in the recovery of an increased number of fertilizable oocytes. The lack of a statistically significant increase in the number of embryos transferred per patient in the combination group as well as the identical number of clinical pregnancies in both groups suggests that this particular combination of clomiphene and human menopausal gonadotropin offers no advantage over the use of clomiphene alone for enhanced follicular recruitment.

Lack of effect of vasectomy on peripheral gonadotrophin and steroid levels

In order to re-assess the possible hormonal consequences of male sterilization, the peripheral plasma levels of lutropin (LH) follitropin (FSH), and dihydrotestosterone sulphate (DHT-S) were measured in a group of 20 healthy men at weekly intervals in the month before and at bimonthly intervals up to 2 years after vasectomy. In addition, the levels of 14 steroids of gonadal and/or adrenal origin were measured before, and then every second month (12 subjects) or every sixth month (8 subjects) following vasectomy. No significant alterations were observed in the levels of any of the hormones studied. The results are interpreted as indicating that in the first 2 years following vasectomy in men there is no consistent or progressive change in the peripheral plasma levels of gonadotrophins or in a variety of steroids of testicular and/or adrenocortical origin.

Effect of vasectomy on the steroid profile of human seminal plasma

The effect of vasectomy on the steroid profile of seminal plasma was studied in 19 healthy men at 4-monthly intervals during a 2-year post-vasectomy period. The steroids analyzed by radioimmunoassays were: androstenedione (A), testosterone (T), dihydrotestosterone (DHT), oestradiol (E2) and the sulphoconjugated forms of pregnenolone (delta 5P-S), dehydroepiandrosterone (DHEA-S), testosterone (T-S), dihydrotestosterone (DHT-S), oestrone (E1-S) and oestradiol (E2-S). The quantitatively most important steroids present in the seminal plasma were DHEA-S, delta 5P-S and DHT-S. Vasectomy resulted in a significant but non-progressive reduction in DHT (40%) and T (23%) levels. The levels of E2, delta 5P-S and DHT-S also exhibited a smaller reduction following vasectomy. No significant changes were observed in the levels of the other steroids studied. The results are interpreted as suggesting that under normal conditions the bulk of the steroids present in the ejaculate is contributed by the accessory reproductive organs. In addition, a significant part of the DHT and T reach the ejaculate together with the sperm directly from the testis and/or epididymis. It is suggested that the normal steroid levels in seminal plasma established in this investigation could serve as reference values in the hormonal evaluation of male infertility.

Endocrine and accessory sex organ function after vasectomy and vasovasostomy

There are no major short- or long-term changes in pituitary testicular axis due to vasectomy. The response of the prostate and epididymis to endogenous may be altered after vasectomy. However, the secretory functions of the two organs return to normal after vasovasostomy. The effects of vasectomy and vasovasostomy on the pituitary gonadal axis and on the accessory sex organs' function are reported.

The hormonal and immunological status of vasectomised men

The concentration of FSH, LH, testosterone and sperm agglutinating and cytotoxic antibodies have been determined in 87 men at varying time intervals after vasectomy. The results indicated that vasectomy is not associated with statistically significant changes in any of these parameters. Furthermore, no correlation existed between the development of sperm antibodies and the peripheral endocrine status of an individual.

The endocrine effects of vasectomy: a prospective five-year study

A prospective study of plasma luteinizing hormone (LH) and testosterone in 54 men for 5 years following vasectomy revealed no significant continuing alteration in either testosterone or LH. Plasma LH levels 1 year after operation were higher than preoperative levels but did not increase further. Stimulation studies (4 years postvasectomy) using human chorionic gonadotropin confirmed acceptable Leydig cell functional reserve.

Endocrine studies of azoospermia. II. Serum steroid levels in obstructive azoospermia

Serum estrone, estradiol, estriol, progesterone, 17 alpha-hydroxyprogesterone, and testosterone were determined in the sera of 25 normal males and 25 patients with obstructive azoospermia. An increase in testosterone and estriol levels, and a decrease in other hormones were demonstrated in patients with obstructive azoospermia. These long-term effects of obstruction of the vas apparently also occur in comparable situations, for example, after vasectomy.

Seminal fructose, citric acid and acid phosphatase before and after vasectomy in man

Seminal fructose, citric acid and acid phosphatase were estimated from 23 healthy males before vasectomy and three months later. Each subject had children and the men volunteered for sterilization because other possibilities of contraception were inapplicable. Vasectomy was performed under local anesthesia in the conventional manner. Semen of all patients was azoospermic three months after vasectomy. In this study, the amounts of seminal fructose and citric acid were significantly higher after vasectomy than before operation. The activity of seminal acid phosphatase was a little less, but the difference was not significant. The increase of seminal fructose and citric acid could be explained by the lack of spermatozoa, which normally use them into their metabolism.

Quantitation of Leydig cells in testicular biopsies of oligospermic men with varicocele

Leydig cell density was evaluated quantitatively in bilateral testicular biopsies from 16 oligospermic men with varicocele. The method utilized for this quantitation is based on the determination of the total number of Leydig cells, Leydig cell clusters, and seminiferous tubules in the entire histologic section of each biopsy, and the calculation of the following indices: mean Leydig cells per seminiferous tubule, mean Leydig cell clusters per seminiferous tubule, and mean Leydig cells per cluster. A significant correlation between Leydig cells per tubule and Leydig cell clusters per tubule was demonstrated, suggesting that determination of Leydig cell clusters per seminiferous tubule in testicular biopsies is an objective and clinically applicable method for quantitative evaluation of Leydig cell density. An association of varicocele with Leydig cell hyperplasia was not noted for the 16 patients studied. In addition, no significant differences in Leydig cell density between right and left testes were found, and no correlation between Leydig cell density and site or degree of varicocele, or age of the patients could be demonstrated. To our knowledge this is the first report of quantitative analysis of Leydig cell density in men with varicocele.

Evaluation of proteohormon concentrations in serum and seminal fluid and its relationship with sperm count

The measurement of FSH, LH, and PRL in serum and seminal fluid of 105 men attending a male infertility clinic and 21 men of proven fertility (controls) did not reveal an interrelationship between the spermatozoal count and the level of the proteo-hormones in both biological fluid except for FSH, which was significantly higher in the serum of men with low as compared to normal sperm count (p less than 0.01). FSH in seminal fluid was significantly lower (p less than 0.01), and LH-like activity significantly higher (p less than 0.01) than in serum, while there was no difference between the respective levels of PRL. These results could be confirmed in 4 patients with azoospermia due to occlusive disease, and in 1 out of 2 vasectomized men. It was demonstrated for the first time that the higher concentration of "LH" in seminal fluid as compared to serum was due to the presence of HCG-beta or a HCG-like material cross-reacting with the antiserum against LH.

In vitro steroid metabolic studies in human testes. II: Metabolism of cholesterol, pregnenolone, progesterone, androstenedione and testosterone by testes of an estrogen-treated man

The effect of long-term in vivo estrogen treatment on in vitro steroidogenesis by the testes of a young man was investigated. In vitro incubation of testicular tissue of this man with 3H-pregnenolone, 3H-progesterone, 3H-androstenedione and 3H-testosterone demonstrated suppression of 17-hydroxylase activity, with little or no effect of the treatment on delta5-3beta-hydroxysteroid oxidoreductase, 5alpha-reductase and aromatase. Increased 20alpha-hydroxysteroid oxidoreductase activity was observed. Determination of intratesticular steroid concentrations led to similar conclusions.

In vitro steroid metabolic studies in human testes I: Effects of estrogen on progesterone metabolism

A technique of incubation of testicular tissue in vitro with radiolabeled precursors was applied in the investigation of the steroid biosynthesis by testes of four young men after long-term, high-dose estrogen treatment. A positive correlation between plasma and testicular steroid levels, and in vitro capacity of the testes to metabolize progesterone was demonstrated. Estrogen administration produced a very significant inhibition of plasma and testicular levels of testosterone. The in vitro synthesis of testosterone from progesterone was very severely impaired; especially 17alpha-hydroxylation of progesterone. 20alpha-hydroxysteroid-dehydrogenase activity was found to be increased after estrogen treatment, both in vivo and in vitro. These findings suggest that testicular 17alpha-hydroxylase activity (and possibly also 17-20 lyase activity) is either under gonadotropin regulation, or is directly suppressed by estrogen. This could result by decreased enzyme synthesis, direct enzyme inhibition or affectation of the cofactors or cytochromes necessary for the enzymatic activity. 20alpha-reduction of C21-steroids would represent an alternative pathway for their catabolism, not regulated by gonadotropin or not affected by estrogen, that would be significant in situations with reduced 17alpha-hydroxylase activity.