Quantitative pathologic changes in the human testis after vasectomy. A controlled study

Totally extraperitoneal laparoscopy-assisted microsurgical vasovasostomy for the treatment of obstructive azoospermia caused by pediatric bilateral inguinal herniorrhaphy

BACKGROUND

Pediatric inguinal hernia repair (IHR) is a common cause of obstructive azoospermia (OA). Yet, the surgical treatment for this kind of OA remains difficult with poor fertility outcome.

OBJECTIVES

To evaluate the safety and effectiveness of totally extraperitoneal laparoscopy-assisted microsurgical vasovasostomy (VV) in the treatment of OA caused by pediatric bilateral IHR.

MATERIALS AND METHODS

Totally, 37 patients with OA caused by pediatric bilateral IHR were enrolled in this study from March 2015 to December 2020 in Shanghai General Hospital. The clinical data and fertility outcomes were collected and analyzed.

RESULTS

All patients enrolled had a history of bilateral IHR at the age of 1-10 years old. The mean age of patients was 27 ± 4.31 (range: 18-35) years. Totally extraperitoneal laparoscopy (TEP) was applied in 31 patients for the exploration and retrieval of pelvic vas deferens end, and 30 of them underwent microsurgical VV successfully. Among the six cases where TEP was not applied, five cases underwent microsurgical anastomosis. Intraoperative exploration revealed that the location of vas deferens injuries included scrotum (2.70%, 1/37), inguinal canal (5.41%, 2/37), pelvic cavity (78.37%, 29/37), and multiple sites (13.51%, 5/37). The mean operation time was 339 ± 96.73 min (range: 130-510 min). There were no surgical complications. Thirty-three cases were followed up for 5-48 months with four cases lost to follow-up. The overall patency rate, pregnancy rate, and natural pregnancy rate were 75.86% (22/29), 46.67% (14/30), and 36.84% (7/19, 3 patients without family planning), respectively. And seven couples conceived through the assisted reproductive technique, two of which using fresh sperm in the ejaculate.

CONCLUSION

TEP laparoscopy-assisted microscopic VV is an effective treatment for patients with OA caused by pediatric bilateral IHR.

Human obstructive (postvasectomy) and nonobstructive azoospermia - Insights from scRNA-Seq and transcriptome analysis

A substantial number of male infertility is caused by azoospermia. However, the underlying etiology and the molecular basis remain largely unknown. Through single-cell (sc)RNA sequencing, we had analyzed testis biopsy samples from two patients with obstructive azoospermia (OA) and nonobstructive azoospermia (NOA). We found only somatic cells in the NOA samples and explored the transcriptional changes in Sertoli cells in response to a loss of interactions with germ cells. Moreover, we observed a germ cell population discrepancy between an OA (postvasectomy) patient and a healthy individual. We confirmed this observation in a secondary study with two datasets at GSM3526588 and GSE124263 for detailed analysis wherein the regulatory mechanisms at the transcriptional level were identified. These findings thus provide valuable information on human spermatogenesis, and we also identified insightful information for further research on reproduction-related diseases.

Vasectomy reversal vs. sperm retrieval with in vitro fertilization: a contemporary, comparative analysis

OBJECTIVE

To explore the primary options available to men who desire fertility after a vasectomy.

DESIGN

Literature review.

SETTING

University of Miami Miller School of Medicine.

PATIENT(S)

Men with a previous vasectomy now seeking fertility.

INTERVENTION(S)

The two main options to achieve paternity for men following vasectomy include vasectomy reversal (VR) and surgical sperm retrieval with subsequent in vitro fertilization (IVF).

MAIN OUTCOME MEASURE(S)

We reviewed and compared the important considerations for men deciding between these 2 options, including: obstructive interval, female partner age, antisperm antibodies, male partner age, female infertility factors, and cost.

RESULT(S)

Both VR and IVF represent reasonable options for the couple seeking fertility after vasectomy. Specific circumstances may favor one modality over another, depending on obstructive interval, possible female fertility factors, female partner age, male partner age, and cost. In the absence of insurance coverage, VR is often more cost-effective than IVF. Alternatively, when a female factor may contribute to infertility in addition to vasectomy, IVF is often the better choice. Antisperm antibodies are unlikely to contribute to infertility following a successful VR.

CONCLUSION(S)

VR or surgical sperm retrieval with IVF are reasonable options for couples seeking children after vasectomy. Pregnancy rates for both options are overall similar, so prior to pursuing either option, a thorough discussion with a reproductive urologist who possesses microsurgical skills in VR and a reproductive endocrinologist with expertise in IVF is imperative. Making a final choice through shared decision-making while considering these points is ideal.

Outcomes of partial intussusception and endo-to-side vasoepididymostomy in men with epididymal obstructive azoospermia

OBJECTIVES

Vasoepididymostomy is an ideal surgical approach for epididymal obstructive azoospermia. The aim of the present study was to compare reproductive outcomes of vasoepididymostomy with several anastomotic techniques, including end-to-side and longitudinal intussusception vasoepididymostomy, and partial intussusception and endo-to-side vasoepididymostomy.

METHODS

A case-control study including 110 infertile men with epididymal obstructive azoospermia with mean age of 35 years was carried out. Univariate and multivariate analyses using clinical factors were carried out to predict patency and non-assisted reproductive technology pregnancy. Johnsen score count and proliferating cell nuclear antigen expression were used as surrogates for spermatogenic function. Operative time, number of 10-0 sutures and late failure rates were also compared.

RESULTS

The overall patency and non-assisted reproductive technology pregnancy rates were 70% and 32%, respectively. Multivariate analyses showed that the presence of motile sperm in the epididymis and a higher spermatogenic function (P < 0.05) were independent predictors for patency, and that a higher spermatogenic function and anastomosis at the caput/corpus (P < 0.001) were predictors for non-assisted reproductive technology pregnancy. The operative time was significantly shorter with partial intussusception and endo-to-side than with the other techniques (P < 0.001), and the number of 10-0 sutures was significantly less with partial intussusception and endo-to-side than with longitudinal intussusception vasoepididymostomy (P < 0.01).

CONCLUSIONS

Partial intussusception and endo-to-side as well as end-to-side and longitudinal intussusception vasoepididymostomy are feasible vasoepididymostomy techniques for epididymal obstruction. Spermatogenic function plays important roles in patency and non-assisted reproductive technology pregnancy after vasoepididymostomy. Depending on the surgeon's expertise, partial intussusception and endo-to-side provides similar functional outcomes to those of more established vasoepididymostomy techniques, such as end-to-side and longitudinal intussusception vasoepididymostomy, and it could therefore be considered an effective technique for seminal reconstruction in patients with epididymal obstructive azoospermia.

Vasectomy and Prostate Cancer Risk: A 38-Year Nationwide Cohort Study

BACKGROUND

A man's risk of prostate cancer has been linked to his prior reproductive history, with low sperm quality, low ejaculation frequency, and a low number of offspring being associated with increased prostate cancer risk. It is, however, highly controversial whether vasectomy, a common sterilization procedure for men, influences prostate cancer risk.

METHODS

We established a cohort of all Danish men (born between 1937 and 1996) and linked information on vasectomy, doctor visits, socioeconomic factors, and cancer from nationwide registries using unique personal identification numbers. Incidence risk ratios for prostate cancer by time since vasectomy and age at vasectomy during the follow-up were estimated using log-linear Poisson regression.

RESULTS

Overall, 26 238 cases of prostate cancer occurred among 2 150 162 Danish men during 53.4 million person-years of follow-up. Overall, vasectomized men had an increased risk of prostate cancer compared with nonvasectomized men (relative risk = 1.15, 95% confidence interval = 1.10 to 1.20). The increased risk of prostate cancer following vasectomy persisted for at least 30 years after the procedure and was observed regardless of age at vasectomy and cancer stage at diagnosis. Adjustment for the number of visits to the doctor and socioeconomic factors did not explain the association.

CONCLUSIONS

Vasectomy is associated with a statistically significantly increased long-term risk of prostate cancer. The absolute increased risk following vasectomy is nevertheless small, but our finding supports a relationship between reproductive factors and prostate cancer risk.

Vasovasostomy and vasoepididymostomy: Review of the procedures, outcomes, and predictors of patency and pregnancy over the last decade

BACKGROUND

In the era of improving assisted reproductive technology (ART), patients with obstructive azoospermia (OA) have 2 options: vasal repair or testicular sperm extraction with intracytoplasmic sperm injection. Vasal repair, including vasovasostomy (VV) and vasoepididymostomy (VE), is the only option that leads to natural conception.

METHODS

This article reviews the surgical techniques, outcomes, and predictors of postoperative patency and pregnancy, with a focus on articles that have reported over the last 10 years, using PubMed database searches.

MAIN FINDINGS

The reported mean patency rate was 87% and the mean pregnancy rate was 49% for a patient following microscopic VV and/or VE for vasectomy reversal. Recently, robot-assisted techniques were introduced and have achieved a high rate of success. The predictors and predictive models of postoperative patency and pregnancy also have been reported. The obstructive interval, presence of a granuloma, and intraoperative sperm findings predict postoperative patency. These factors also predict postoperative fertility. In addition, the female partner's age and the same female partner correlate with pregnancy after surgery.

CONCLUSION

In the era of ART, the physician should present and discuss with both the patient with OA and his partner the most appropriate procedure to conceive by using these predictors.

Testicular Lesions in Rats Treated with a Sympatholytic Hypotensive Agent (Losulazine)

Groups of 25 male Sprague-Dawley rats were treated orally with losulazine at 0 (vehicle control), 4, 8, 16, or 32 mg/kg/day for 1 year. Daily clinical signs, weekly food consumption and body weight changes, and terminal hematologic and blood chemistry values were evaluated. Terminal urinalysis in 10 randomly selected rats from all groups and levels of serum luetinizing hormone, prolactin, and testosterone from control, low-, and high-dose groups were also evaluated. Fertility was determined in eight randomly selected rats from each group at 35–49 weeks. Reversibility of breeding performance was evaluated in 10 rats treated for 30 weeks and allowed to recover for 17 weeks. Selected organs were weighed and the testes and epididymides were microscopically evaluated in all rats that survived through the 1 year treatment period.

Rats treated with losulazine showed dosage-dependent ptosis, somnolence, fecal softening, and decreased food consumption with a corresponding retarded body weight gain. There were no biologically significant changes in hematologic, blood chemistry, or urinalysis values between treated and control rats. Relative spleen, heart, adrenal, and brain weights were increased in treated rats. There was a reversible dosage and time-dependent decreased fertility in rats treated with losulazine for 6–12 months. The incidence of testicular tubular atrophy/degeneration, usually confined to the subcapsular areas of the testes, and concentration of degenerate ge.minal cells in the epididymides, were increased in treated compared to vehicle control rats. Testicular lesions were not dosage related, were minimal to mild after 1 year of treatment, and were not attended by a decrease in relative testicular weights. Decreased fertility was not correlated with the apparently treatment-related testicular lesions. It could not be determined whether the minor testicular lesions seen in rats treated with losulazine were related to stressful conditions the rats were apparently under or to the effects of the drug on the hypothalamus-pituitary-gonadal axis or the sympathetic nervous system.

Long-Term Outcome of Low Scrotal Approach Orchiopexy without Ligation of the Processus Vaginalis

PURPOSE

We performed low scrotal approach orchiopexy in patients with prescrotal cryptorchidism. The processus vaginalis was not ligated if it was not widely patent. We retrospectively evaluated the long-term outcomes of low scrotal approach orchiopexy without processus vaginalis ligation.

MATERIALS AND METHODS

A total of 137 patients (227 testes) were diagnosed with prescrotal cryptorchidism between October 2009 and April 2014. All patients underwent low scrotal approach orchiopexy. Mean age at surgery was 34.9 months. The processus vaginalis was deemed to be not widely patent when a sound could not be passed into the abdominal cavity through the internal inguinal ring, and the processus vaginalis was not ligated in such cases.

RESULTS

Intraoperative findings revealed that the processus vaginalis was widely patent in 10 testes and was not widely patent in 217. A widely patent processus vaginalis was closed via scrotal approach in 5 testes, while an inguinal approach was necessary in 5. Median followup was 44 months (range 20 to 73). Postoperative complications included reascending testis in 1 case where an inguinal approach was necessary. No patient manifested testicular atrophy or inguinal hernia.

CONCLUSIONS

Low scrotal approach orchiopexy is a useful and safe procedure for treating patients with prescrotal cryptorchidism. Ligation is unnecessary when the processus vaginalis is not widely patent.

Apoptosis in testicular tissue of rats after vasectomy: evaluation of eNOS, iNOS immunoreactivities and the effects of ozone therapy

OBJECTIVE

We aimed to investigate the changes in endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) expression and apoptotic index in rat testicular tissue, as well as serum and seminal plasma sex hormone levels after vasectomy, and the effect of ozone therapy (OT).

MATERIAL AND METHODS

Adult male Wistar rats were used (n=6 per group). Control (G1), sham for 4 weeks (G2) or 6 weeks (G3), orchiectomy at the 4(th) (G4) or 6(th) (G5) week after left vasectomy, orchiectomy at the 4(th) (G6) or 6(th) (G7) week after bilateral vasectomy, orchiectomy after 6 weeks OT following left (G8) or bilateral (G9) vasectomy, orchiectomy after 6 weeks OT (G10).

RESULTS

In the left testes, while there were increases in eNOS and iNOS immunoreactivity and apoptotic indexes in G4 and G5, no changes were observed in contralateral testis. These values increased in G6 and G7, while OT inhibited these parameters in the left testis of G8 and both testes of G9. Sex hormone levels did not show any changes after vasectomy and ozone therapy.

CONCLUSION

While OT was found to be protective against some parameters mentioned above under stress conditions, it seemed to cause some harmful effects when used in healthy conditions.

Congenital bilateral absence of the vas deferens: the impact of spermatogenesis quality on intracytoplasmic sperm injection outcomes in 108 men

In azoospermic men with congenital bilateral absence of the vas deferens (CBAVD), it is not known whether the outcomes of intracytoplasmic sperm injection (ICSI) depend on the quality of testicular spermatogenesis (as determined histopathologically). We retrospectively studied the impact of spermatogenesis quality on ICSI outcomes in 108 azoospermic men with CBAVD consulting in a university hospital's department of andrology and reproductive biology. As part of an ICSI program, sperm samples were obtained from the epididymis [by microsurgical epididymal sperm aspiration (MESA); n = 47] or the testis [by testicular sperm extraction (TESE); n = 14] or both (MESA + TESE, n = 47). In the TESE group (i.e., TESE-only and MESA + TESE), spermatogenesis was normal in 21 of the 108 men (19.4%) and hypospermatogenesis occurred in 33 (30.5%). The fertilization rate was significantly lower in the hypospermatogenic group than in the normospermatogenesis group (65.6 and 72.9%, respectively; p = 0.02); this was also true for the embryo cleavage rate (88.6 and 92.1%, respectively; p = 0.007), and the proportion of embryos with fewer than 30% of enucleate fragments (79.5 and 86.9%, respectively; p = 0.02). Our study results showed that impaired spermatogenesis had a negative impact on certain early-stage biological outcomes of ICSI. In CBAVD, male factors are likely to exert a harmful effect on the early stages of embryo development.

Antisperm antibodies: invaluable tools toward the identification of sperm proteins involved in fertilization

The identification of sperm proteins involved in fertilization has been the subject of numerous investigations. Much interest has been dedicated to naturally occurring antisperm antibodies (ASA) and their impact in fertility. Their presence in men and women has been associated with 2-50% of infertility cases. ASA may impair pre- and post-fertilization steps. Experimental models have been developed using sperm proteins as immunogens to evaluate their involvement in sperm function. Our team has pursued investigations to assess ASA presence in biological fluids from patients consulting for infertility and their effect on fertilization. We found ASA in follicular fluids with ability of inducing the acrosome reaction and blocking sperm-zona pellucida interaction and used them to identify sperm entities involved in these events. We generated and utilized antibodies against proacrosin/acrosin to characterize the sperm protease system. We implemented an ELISA to detect proacrosin/acrosin antibodies in human sera and evaluated their impact upon fertility by developing in vitro assays and a gene immunization model. This review presents a summary of ASA history, etiology, current approaches for detection and effects upon fertility. ASA (naturally occurring, generated by animal immunization and/or of commercial origin) are invaluable tools to understand the molecular basis of fertilization, better diagnose/treat immunoinfertility and develop immunocontraceptive methods.

Long-term study of vasectomy in Macaca radiata--histological and ultrasonographic analysis of testis and duct system

This study was aimed to investigate the long-term effect of vasectomy using the bonnet monkey (Macaca radiata) as a primate animal model. Animals weighing around 6 to 8 kg were randomly chosen for bilateral, unilateral vasectomy and sham-control. The postoperative periods of six months and two years were considered as short and long-term, respectively. Sperm were collected and subjected to analysis before euthanasia. The testes and epididymides were excised from euthanized animals then embedded in paraffin. Normal histological changes were observed in sham-operated animals and short-term contralateral testes. In contrast, marked alterations were observed in the testes and epididymides of both short and long-term groups. Seminiferous epithelium was thinned out showing marked depletion of germ cells in long-term; only a thin layer of Sertoli cells, spermatogonia, and fewer spermatocytes were seen. Exfoliation of germ cells and the occurrence of multinucleated giant cells were common features in these tubules. The epididymal tubular lumens were greatly dilated with accumulated spermatozoa in short and long-term animals; significant defects were observed in the epithelium of the long-term animals. Microscopic spermatic granulomas were noticed in epididymides and the vas deferens. Large granulomas were seen in long-term vasectomized monkeys, frequently compressing the surrounding structures. These granulomas could be visualized in ultrasound, however, only at the late stage of its occurrence. Sperm collected from the unilateral vasectomized animals showed a poor motility score in the capillary mucus penetration test (CMPT). Results indicate that the changes observed after vasectomy might be due to pressure initially, whereas in the long-term the damage was supplemented by autoimmune attack. With immunoglobulin (IgG) deposition in contra-lateral unoperated testis of unilateral vasectomized animals it also showed degenerative changes and a concomitant drop in sperm quality. Although, granulomatous reactions were observed in the epididymis and vas deferens but testes were spared from such reactions even in the long-term.

Immunization against recombinant GnRH-I alters testicular structure in an experimental boar model

The aim of this study was to evaluate and to compare testicular tissue in immunized and control boars. Eighteen male piglets, aged 12 weeks, were vaccinated twice intramuscularly with a maltose-binding protein-gonadotropin-releasing hormone I hexamer peptide (MBP-GnRH-I6). Blood samples were taken at 12, 18, 21 and 24 weeks of age. Serum concentrations of testosterone and GnRH-I antibodies were determined by radioimmunoassay. The pigs were sacrificed 6 weeks after the second immunization. Testicular weight and size were recorded and tissue samples were collected for histological examination. The results demonstrated that active immunization against MBP-GnRH-I6 increased serum GnRH-I antibody levels (P < 0.05) and reduced serum concentrations of testosterone (P < 0.05) when compared with controls. Histological studies performed on testicular tissue revealed clear signs of atrophy in the MBP-GnRH-I6 immunized pigs, and a significant reduction (P < 0.05) in paired testes weight and size were seen in the treated boars. Microscopically, the mean diameter of the seminiferous tubules was markedly reduced (P < 0.01). Spermatogonia were visible, as well as few spermatocytes, but no spermatozoa were detected in the seminiferous tubules. Ultramicroscopic analysis of testicular tissue revealed an increase in the thickness of the basement membrane and extensive damage in the cell organelles of the treated animals, including small spermatogonial size, decreased number of mitochondria and endoplasmic reticulum in the primary spermatocyte and spermatid, a shallow hollow for nuclear membranes in Sertoli cells and mitochondrial vacuolation in Leydig cells. We conclude that MBP-GnRH-I6 induces severe atrophy in the testes of immunized boars.

Factors predicting overall success: a review of 747 microsurgical vasovasostomies

OBJECTIVES

Advances in surgical techniques have improved the outcome of microsurgical vasovasostomy (VV). We performed a retrospective analysis of surgical procedures to determine outcomes and predictors of VV success, to develop Kaplan-Meier Curves for predicting VV outcomes and to evaluate the use of alpha-glucosidase (AG) to predict outcomes.

PATIENTS AND METHODS

We undertook a retrospective analysis of 747 modified 1-layer microsurgical VV procedures performed between 1984 and 2000. Obstructive interval, partner status, social status preoperatively and method of vasal obstruction, vasal fluid quality and sperm granuloma intraoperatively were compared with outcome results. Parameters evaluated at follow-up included semen analysis, AG concentration in ejaculate fluid and pregnancy rates.

RESULTS

The overall patency rate was 86% and pregnancy rates were 33% and 53% at 1 and 2 years after primary VV, respectively. Preoperative factors associated with successful outcome and pregnancy included shorter obstructive interval and same female partner (p < 0.05). Intraoperative factors predicting success included the use of surgical clips instead of suture at vasectomy, the presence of a sperm granuloma, the presence and quality of vasal fluid, and the presence and quality of sperm in vasal fluid. Further, increased AG in the postoperative semen predicted improved patency and pregnancy outcomes.

CONCLUSION

This study confirms the effectiveness of VV for vasectomized men who wish to father children. It also demonstrates that preoperative and intraoperative factors are predictive of the VV outcome. Postoperative AG is also a useful marker of patency and it appears to predict pregnancy outcome.

Long-term effect of vasectomy on spermatogenesis in men: a morphometric study

Spermatogenic damage may occur after vasectomy, and the damage is pressure mediated, occurring when the occluded reproductive tract is unable to accommodate additional sperm produced by the testis. This study aimed to determine the long-term effect of vasectomy on spermatogenesis in humans and clarify how the balance between sperm production in the testis and sperm storage in or removal from the tract might be maintained. During inguinal hernia repair, an open biopsy was performed to obtain testicular tissue blocks from 51 Chinese men (aged ≥50 years), of whom 25 (control group) had not undergone vasectomy and 26 (vasectomized group) had undergone bilateral vasectomy 22-42 years before. Methacrylate resin-embedded testicular sections were made, and morphometric studies were performed using light microscopy. In addition, sizes of the testis and epididymis were estimated with ultrasonography. The testicular tissue blocks obtained from one control and seven vasectomized men consisted almost completely of connective tissue. In the other 43 men, significant differences were not found between the two groups in the testicular or epididymal size, qualitative histology or quantitative parameters including the mean diameter or volume fraction of the seminiferous tubules. In conclusion, sperm production and sperm storage/removal reached a static equilibrium after vasectomy, likely due to spermatogenic degeneration or less sperm production as a result of aging or due to vasectomy-induced testicular (interstitial) fibrosis. Thus, complications that might occur in association with overproduction of sperm and distension of the tract would disappear or be relieved with time.

Is the adult Sertoli cell terminally differentiated?

New data have challenged the convention that the adult Sertoli cell population is fixed and unmodifiable. The Sertoli cell has two distinct functions: 1) formation of the seminiferous cords and 2) provision of nutritional and structural support to developing germ cells. For these to occur successfully, Sertoli cells must undergo many maturational changes between fetal and adult life, the main switches occurring around puberty, including the loss of proliferative activity and the formation of the blood-testis barrier. Follicle-stimulating hormone plays a key role in promoting Sertoli cell proliferation, while thyroid hormone inhibits proliferative activity in early postnatal life. Together these regulate the Sertoli-germ cell complement and sperm output in adulthood. By puberty, the Sertoli cell population is considered to be stable and unmodifiable by hormones. But there is mounting evidence that the size of the adult Sertoli cell population and its maturational status is modifiable by hormones and that Sertoli cells can gain proliferative ability in the spermatogenically disrupted hamster and human model. This new information demonstrates that the adult Sertoli cell population, at least in the settings of testicular regression in the hamster and impaired fertility in humans in vivo and from mice and men in vitro, is not a terminally differentiated population. Data from the hamster now show that the adult Sertoli cell population size is regulated by hormones. This creates exciting prospects for basic and clinical research in testis biology. The potential to replenish an adult Sertoli-germ cell complement to normal in a setting of infertility may now be realized.

Source of selenium supplementation influences testis selenium content and gene expression profiles in Single Comb White Leghorn roosters

Spermatogenesis is a tightly regulated, selenium-dependent process. Nutritional deficiencies, including Se, have been associated with decreased fertility. During Se depletion, testes preferentially retain Se while other tissues are depleted. This study was aimed at evaluating the effect of Se source (inorganic or organic yeast derived) on testes weight, Se content, and gene expression. At 17 weeks of age, roosters were randomly assigned to one of three treatments: basal diet (control), basal diet + 0.3 mg organic Se/kg organic yeast-derived Se (YS; Sel-Plex®, Alltech Inc.), or basal diet + 0.3 mg inorganic Se /kg inorganic Se as sodium selenite (SS). At 40 weeks of age, seven roosters from each treatment were euthanized and testes removed. Testes weight did not differ between treatments, but Se content was greater (P ≤ 0.01) in YS than SS and control. Testicular differential gene expression profiling was accomplished using the Affymetrix Genechip® chicken genome array. Ingenuity® pathway analysis revealed that Se supplementation, regardless of source, results in the up-regulation of genes governing cell structure/morphology. The enrichment of such pathways was greater with YS than SS. These expression patterns suggest that aside from playing a role in antioxidant defense, Se, especially in the organic YS form, is useful for maintaining testicular cell structure.

Reduced numbers of Sertoli, germ, and spermatogonial stem cells in impaired spermatogenesis

A key step in the investigation of male infertility is the appropriate classification of impaired spermatogenesis. In this study, we precisely identified Sertoli and distinct germ-cell types in the rat, the mouse, and in the human testis. As a proof of principle, we studied testis biopsy samples from azoospermic patients with defined spermatogenic defects. Remarkably, we found that already the numbers of Sertoli cells, spermatogonia and a subset of spermatogonia including stem cells are significantly reduced in patients with maturation arrest at the level of primary spermatocytes (n=33) compared with patients with histologically normal spermatogenesis (n=33). In patients with hypospermatogenesis (n=44) a significant reduction of spermatogonial cell numbers was observed. The numbers of primary and diplotene spermatocytes were reduced by 84%. However, the strongest reduction (96%) was revealed in the numbers of spermatids in patients with maturation arrest. In contrast, patients with hypospermatogenesis showed only modestly reduced numbers of spermatocytes and spermatids compared with normal spermatogenesis. No correlation was found with age or obstruction. For a detailed analysis of the patients, we distinguished between 'pool of founder cells'-related deficiencies (reduced numbers of Sertoli cells, spermatogonia, and spermatogonial stem cells) and 'meiotic' deficiencies (reduced numbers of spermatocytes, meiotic divisions, and spermatids). Interestingly, patients with maturation arrest showed meiotic deficiencies (36%), while the majority additionally demonstrated deficiencies in the founder pool (58%). In contrast, patients with normal spermatogenesis most often had no deficiencies at all (45%) or founder pool-related deficiencies (33%) but an apparently normal meiosis. This is the first report showing that many infertile patients face besides meiotic defects the problem of reduced numbers of Sertoli cells, spermatogonia, and spermatogonial stem cells.

Increased sperm DNA fragmentation in patients with vasectomy reversal has no prognostic value for pregnancy rate

PURPOSE

We evaluated sperm DNA fragmentation in patients with vasectomy reversal and its prognostic value to determine spontaneous and assisted reproductive technique pregnancy rates.

MATERIALS AND METHODS

We prospectively assessed DNA fragmentation with the sperm chromatin structure assay in postoperative semen samples of 70 patients with vasectomy reversal. At a median +/- SD followup of 4.3 +/- 0.5 years pregnancy rates were recorded.

RESULTS

DNA fragmentation in patients with vasectomy reversal was significantly increased vs that in proven fertile controls (30.2% +/- 20.1% vs 15.3% +/- 5.4%, p <0.001). Significant negative correlations were found between DNA fragmentation index and total sperm count, progressive motility, total number of progressive sperm, normal morphology and sperm vitality (-0.325 <r <-0.805). The obstructive interval did not correlate with DNA fragmentation. The spontaneous pregnancy rate was 46%. Significantly higher log total progressive sperm motility (p = 0.021) and a trend toward lower female age (p = 0.064) were detected in the spontaneous vs the no pregnancy group. No association was found between DNA fragmentation and the pregnancy rate.

CONCLUSIONS

Increased DNA fragmentation is present in semen samples of men after vasectomy reversal vs fertile controls but DNA fragmentation is not associated with spontaneous or assisted reproductive technique pregnancy rates in these patients.

Effects of hemodialysis on testicular volume and oxidative stress in humans

PURPOSE

Male infertility is a serious problem in patients on hemodialysis. Our understanding is that end stage renal disease or hemodialysis causes poor semen quality but the mechanism leading to impaired spermatogenesis is largely unknown.

MATERIALS AND METHODS

Testicular volume in 120 patients on maintenance hemodialysis was compared with that in age matched healthy controls. Volume was correlated with clinical findings. In 10 testicular biopsy specimens from patients on hemodialysis who visited our infertility clinic Western blotting was performed to examine the generation of 4-HNE modified proteins, which are markers of oxidative stress, and the expression of proliferating cell nuclear antigen. Interstitial fibrosis was determined by Masson's trichrome staining.

RESULTS

Mean bilateral testicular volume in patients on hemodialysis was significantly smaller than that in healthy controls (31.7 vs 36.4 ml, p <0.01) in a hemodialysis duration dependent manner (r = -0.32, p <0.01). The increase in serum ferritin correlated inversely with testicular volume (r = -0.25, p <0.01). The generation of 4-HNE modified proteins was significantly increased 3.1-fold in patients on hemodialysis, following the 60% decreased expression of proliferating cell nuclear antigen. Quantitative analysis of Masson's trichrome staining revealed increased interstitial fibrosis in patients on hemodialysis compared with that in controls (41.5% vs 14.8%, p <0.01). Serum ferritin, proliferating cell nuclear antigen expression and interstitial fibrosis correlated with the generation of 4-HNE modified proteins (p <0.05).

CONCLUSIONS

Testicular volume, which is a parameter of spermatogenesis, is impaired in patients on hemodialysis and oxidative stress is considered to be involved in the process. Serum ferritin is a useful parameter for predicting oxidative stress in the testis.

Techniques for surgical retrieval of sperm prior to intra-cytoplasmic sperm injection (ICSI) for azoospermia

BACKGROUND

Azoospermia, the absence of sperm in ejaculated semen, is the most severe form of male-factor infertility and is present in approximately 5% of all investigated infertile couples. The advent of intra-cytoplasmic sperm injection (ICSI) has transformed treatment of this type of severe male-factor infertility. Sperm can be retrieved for ICSI from either the epididymis or the testis, depending on the type of azoospermia.

OBJECTIVES

To evaluate the efficacy of the various surgical retrieval techniques for men with obstructive or non-obstructive azoospermia prior to ICSI.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (November 2007), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 4), MEDLINE (1966 to November 2007), EMBASE (1980 to November 2007), Biological Abstracts (1980 to November 2007), and reference lists of identified articles.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the effectiveness of different sperm-retrieval techniques in men with azoospermia prior to ICSI. Due to the lack of RCTs, non-randomised trials that used the participants as their own control were also considered in the review but their results were not included in the meta-analysis.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Study authors were contacted for additional information.

MAIN RESULTS

The search was revised and re-run in November 2007. No new trials were located therefore the results of the updated review remain unchanged from those published in 2006. Two trials involving 98 men were included. The first small RCT had 59 participants and compared two epididymal techniques. The trial gave limited evidence that microsurgical epididymal sperm aspiration (MESA) achieved a significantly lower pregnancy rate (one pregnancy in 29 procedures compared with seven pregnancies in 30 procedures; OR 0.19, 95% CI 0.04 to 0.83) and fertilisation rate (OR 0.16, 95% CI 0.05 to 0.48) than the micropuncture with perivascular nerve stimulation technique. The other RCT comparing two testicular aspiration techniques (TSA) in 39 participants gave no statistically significant evidence for the superiority of the ultrasound-guided technique compared to the aspiration technique without ultrasound. TSA with ultrasound resulted in pregnancy in three out of 16 participants compared with four out of 23 participants (OR 1.10, 95% CI 0.21 to 5.74).

AUTHORS' CONCLUSIONS

There is insufficient evidence to recommend any specific sperm retrieval technique for azoospermic men undergoing ICSI. In the absence of evidence to support more invasive or more technically difficult methods, the review authors recommend the least invasive and simplest technique available. Further randomised trials are warranted, preferably multi-centred trials. The classification of azoospermia as obstructive and non-obstructive appears to be relevant to a successful clinical outcome and a distinction according to the cause of azoospermia is important for future clinical trials.

Clinical, ultrasonographic and pathological features following unilateral vasectomy in rams

The effects of vasectomy on testes and related structures of animal species and men are largely disputable. These possible effects were studied in the ram, an established experimental animal model used to investigate genitalia pathophysiology. In each of five rams, vasectomy in the left spermatic cord was carried out; subsequently, the clinical and ultrasonographic features were monitored up to 12 months post-operatively. The rams were sequentially euthanatized 1, 3, 6, 9 and 12 months post-operatively; gross- and histo-pathological examination of their testes and related structures were carried out. Four of the five rams developed sperm granulomas at the proximal to the testis end of vas deferens or/and at the tail of the epididymis; these were palpable from the first and the third month after vasectomy, respectively. Ultrasonographic findings on the vasectomy side were increased size and echogenicity of the epididymal tail, as well as anechoic areas, representing sperm granulomas, visible in the epididymal tail 1 week after vasectomy and in the proximal to the testis end of vas deferens 4 weeks after vasectomy. Gross pathological findings were limited on the vasectomy side and included adhesions between the parietal and the visceral vaginal tunic, enlarged and firm epididymal tail and presence of sperm granulomas at the epididymal tail or/and at the proximal to the testis end of vas deferens; the granulomas contained creamy material. Histopathological changes were observed mainly in the epididymal tails, consisting of a central mass of spermatozoa, surrounded by a layer of macrophages, surrounded in turn by loose vascular connective tissue rich in lymphocytes and plasma cells. With the exception of signs of mild hypospermatogenesis observed in one ram euthanatized 9 months after surgery, and of a slight increase in seminiferous tubule diameter and in seminiferous epithelium height in the rams euthanatized 6 and 9 months after surgery, which are both findings of no clinical importance, no clinical, ultrasonographic, gross- or other histo-pathological changes were observed in the testicular parenchyma during a 12-month post-operative period. These results demonstrate that vasectomy has little if any detrimental effect on the morphologic characteristics of the spermatogenesis in rams.

Techniques for surgical retrieval of sperm prior to ICSI for azoospermia

BACKGROUND

Azoospermia, the absence of sperm in ejaculated semen, is the most severe form of male factor infertility and is present in approximately 5% of all investigated infertile couples. The advent of intra-cytoplasmic sperm injection (ICSI), however, has transformed treatment of this type of severe male factor infertility. Sperm can be retrieved for ICSI from either the epididymis or the testis depending on the type of azoospermia.

OBJECTIVES

To evaluate the efficacy of the various surgical retrieval techniques for men with obstructive or non obstructive azoospermia prior to ICSI.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (searched 12 Jan 2005), Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2004), MEDLINE (1966 to Nov 2004), EMBASE (1980 to Dec 2004), and Biological Abstracts (1980 to Nov 2004) and reference lists of articles.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the effectiveness of sperm retrieval techniques in men with azoospermia prior to ICSI. Due to the lack of RCTs, non-randomised trials that used the participants as their own control, were also considered in the review but not included in the meta-analysis.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information.

MAIN RESULTS

Two trials involving 98 men were included. The first small RCT had 59 participants and compared two epididymal techniques. The trial gave limited evidence that microsurgical epididymal sperm aspiration (MESA) achieved significantly lower pregnancy (One pregnancy in 29 procedures compared with seven pregnancies in 30 procedures, OR 0.19, 95% CI 0.04 to 0.83) and fertilisation rates (OR 0.16, 95% CI 0.05 to 0.48) than the micropuncture with perivascular nerve stimulation technique. The other RCT comparing two testicular techniques in 39 participants gave no statistically significant evidence about the superiority of the ultrasound guided aspiration technique compared to the aspiration technique without ultrasound guidance. TSA with ultrasound resulted in pregnancy in 3 out of 16 participants and TSA without ultrasound in four pregnancies with 23 participants (OR 1.10, 95% CI 0.21 to 5.74)

AUTHORS' CONCLUSIONS

There is insufficient evidence to recommend any specific sperm retrieval technique for azoospermic men undergoing ICSI. In the absence of evidence to support more invasive or more technically difficult methods the reviewers recommend the least invasive and simplest technique available. Further randomised trials are warranted, preferably multi-centred trials. The classification of azoospermia as obstructive and non-obstructive appears to be relevant to a successful clinical outcome so a distinction according to the cause azoospermia is important for future clinical trials.

Testis morphology in patients with idiopathic hypogonadotropic hypogonadism

BACKGROUND

Adult patients with idiopathic hypogonadotropic hypogonadism (IHH) typically present with absent puberty and therefore have prepubertal testes. IHH is recognized as one of the few curable causes of male infertility and is often effectively treated with either gonadotropins or pulsatile GnRH therapy. The objective of this study was to determine the structure of the testis prior to initiation of treatment.

METHODS AND RESULTS

Eight adult IHH patients with prepubertal testes (<4 ml), with no previous gonadotropin therapy and with no history of cryptorchidism underwent open bilateral testicular biopsy prior to the initiation of hormonal treatment. The testes of all patients showed seminiferous cords separated by interstitium composed of blood vessels, connective tissue cells and collagen fibres but typical adult Leydig cells were absent. The cords contained only Sertoli cells and early type A spermatogonia. The spermatogonia mostly resided in the centre of the cords and were often large, typical of gonocytes. Sertoli cells appeared immature with ovoid nuclei devoid of infoldings and cytoplasm that lacked polarity. Tight junctional complexes commonly found connecting adult Sertoli cells were lacking.

CONCLUSIONS

These results demonstrate that the immature testes from patients with the severe form of IHH possess early spermatogonia that could possibly reinitiate spermatogenesis with appropriate hormone stimulation. Therefore, the immature testis of this IHH subset resembles those of prepubertal boys and may provide important biologic and genetic insights into testicular development.

Etiology-specific outcomes of intracytoplasmic sperm injection in azoospermic patients

OBJECTIVE

To assess fertilization, pregnancy, and miscarriage rates after intracytoplasmic sperm injection (ICSI) with epididymal or testicular spermatozoa from different types of azoospermia.

DESIGN

Retrospective study.

SETTING

Academic medical center and private fertility center.

PATIENT(S)

Two hundred twelve patients underwent 257 ICSI cycles.

INTERVENTION(S)

Cycles of ICSI were divided into four groups according to the etiology of azoospermia: A (nonobstruction), B (postvasectomy), C (congenital obstruction), and D (obstruction due to infection). Testicular sperm aspiration and percutaneous epididymal sperm aspiration were the sperm retrieval methods used for ICSI.

MAIN OUTCOME MEASURE(S)

Fertilization, pregnancy, and miscarriage rates.

RESULT(S)

Normal fertilization rates were higher in groups C (67.7%) and B (64.1%) compared with groups A (47.3%) and D (58.9%). Although lower pregnancy rates were seen in group A, no statistical differences were detected among groups. However, the miscarriage rate was higher in group A (45.6%) compared with groups B (25.25%), C (24%), and D (22.58%).

CONCLUSION(S)

Although no differences were detected in the pregnancy rates across groups, fertilization and implantation rates were higher in patients with congenital obstruction of the seminal path. The pregnancy rate was higher and the miscarriage rate lower when epididymal sperm was used compared with testicular sperm.

Quantitative (stereological) study of the effects of vasectomy on spermatogenesis in rabbits

Using stereological methods, especially the optical disector for unbiased estimation of nuclear number, our recent study demonstrated that long-term (6 or 12 months) vasectomy in the rhesus monkey had no significant effects on spermatogenesis (Peng et al. Reproduction 2002, 124, 847-856). This study aimed to determine the scenario in the rabbit using the same morphometric methodology. Three groups of normal male Japanese white rabbits (aged 4-5 months) were subjected to unilateral vasectomy; 10 days, 6 months and 12 months later both testes and epididymides were removed. Testicular and epididymal methacrylate-embedded sections were obtained for stereology. Vasectomy-induced damage to spermatogenesis was observed, primarily sloughing of spermatogenic cells with a greater reduction in the number of advanced (adluminal) cells. The damage was most severe at 10 days, occurring in all the testes on the vasectomized side and involving sloughing of even type A spermatogonia, the number of which returned to normal at 6 and 12 months. Damage was less severe at 6 and 12 months, being found in half of the testes of the vasectomy side, in which the total numbers of later germ cell types were 24.0-59.1% (spermatocytes) and 0.3-11.6% (spermatids) of control at 6 months, and 20.1-22.1% (spermatocytes) and 0.4-12.0% (spermatids) of control at 12 months. By contrast, Sertoli cell number per testis was unchanged following vasectomy in any group. Epididymis on the vasectomy side, especially at 10 days and 6 months, appeared larger than on the contralateral side, but this difference was not statistically significant, and no sperm granuloma was seen in the epididymis.

Stereological analysis of the human testis after vasectomy indicates impairment of spermatogenic efficiency with increasing obstructive interval

OBJECTIVE

To quantify germ cell loss and the extent of testicular fibrosis in vasectomized patients of varying obstructive intervals.

DESIGN

Retrospective study.

SETTING

Specialized male reproductive surgery and endocrinology service.

PATIENT(S)

Thirty-four vasectomized patients 1-20 years after surgery and 10 normal subjects.

INTERVENTION(S)

Thirty-four testicular biopsies taken at the time of vasectomy reversal (vasovasostomy). Control biopsies taken from 10 normal men at the time of vasectomy.

MAIN OUTCOME MEASURE(S)

Stereological assessment of testicular germ cell populations and testicular fibrosis.

RESULT(S)

Vasectomy caused a significant decrease in germ cells in the later stages of spermatogenesis, with significant reductions in pachytene spermatocytes (by 18%), round spermatids (by 40%), elongating spermatids (by 23%), and elongated spermatids (by 39%). The loss of spermatids showed a significant relationship with obstructive interval. A significant 2.7-fold increase in total (peritubular plus interstitial) fibrosis was observed, which showed a positive relationship with obstructive interval. Decreased germ cell populations and fibrosis did not seem to be related to sperm antibody levels nor to sperm counts obtained up to 2 years after vasovasostomy.

CONCLUSION(S)

Vasal obstruction results in significant reductions in germ cells in the later stages of spermatogenesis and increases in testicular fibrosis, both worsening with an increasing obstructive interval. Testicular damage after vasectomy might impact upon the prospects for reversal.

Extracellular matrix: recent advances on its role in junction dynamics in the seminiferous epithelium during spermatogenesis

Spermatogenesis takes place in the seminiferous epithelium of the mammalian testis in which one type A1 spermatogonium (diploid, 2n) gives rise to 256 spermatids (haploid, 1n). To accomplish this, developing germ cells, such as preleptotene and leptotene spermatocytes, residing in the basal compartment of the seminiferous epithelium must traverse the blood-testis barrier (BTB) entering into the adluminal compartment for further development into round, elongating, and elongate spermatids. Recent studies have shown that the basement membrane in the testis (a modified form of extracellular matrix, ECM) is important to the event of germ cell movement across the BTB because proteins in the ECM were shown to regulate BTB dynamics via the interactions between collagens, proteases, and protease inhibitors, possibly under the regulation of cytokines. While these findings are intriguing, they are not entirely unexpected. For one, the basement membrane in the testis is intimately associated with the BTB, which represents the basolateral region of Sertoli cells. Also, Sertoli cell tight junctions (TJs) that constitute the BTB are present side-by-side with cell-cell actin-based adherens junctions (AJ, such as basal ectoplasmic specialization [ES]) and intermediate filament-based desmosome-like junctions. As such, the relative morphological layout between TJs, AJs, and desmosome-like junctions in the seminiferous epithelium is in sharp contrast to other epithelia where TJs are located at the apical portion of an epithelium or endothelium, furthest away from ECM, to be followed by AJs and desmosomes, which in turn constitute the junctional complex. For another, anchoring junctions between a cell epithelium and ECM found in multiple tissues, also known as focal contacts (or focal adhesion complex, FAC, an actin-based cell-matrix anchoring junction type), are the most efficient junction type that permits rapid junction restructuring to accommodate cell movement. It is therefore physiologically plausible, and perhaps essential, that the testis is using some components of the focal contacts to regulate rapid restructuring of AJs between Sertoli and germ cells when germ cells traverse the seminiferous epithelium. Indeed, recent findings have shown that the apical ES, a testis-specific AJ type in the seminiferous epithelium, is equipped with proteins of FAC to regulate its restructuring. In this review, we provide a timely update on this exciting yet rapidly developing field regarding how the homeostasis of basement membrane in the tunica propria regulates BTB dynamics and spermatogenesis in the testis, as well as a critical review on the molecular architecture and the regulation of ES in the seminiferous epithelium.

The Impact of Obstructive Interval and Sperm Granuloma on Outcome of Vasectomy Reversal

PURPOSE

We studied the impact of the interval from vasectomy to reversal and presence of sperm granuloma on outcomes of reversal.

MATERIALS AND METHODS

A total of 213 microsurgical vasectomy reversals performed by a single surgeon were stratified according to obstructive intervals of less than 5 years, 5 to 10 years, 10 to 15 years and greater than 15 years. The effects of obstructive interval on patency and pregnancy rates were assessed using multivariate logistical regression. The impact of sperm granuloma on patency and pregnancy was assessed using the chi-square test.

RESULTS

Patency did not change with increasing obstructive intervals as can be seen with 91% patency at less than 5 years, 88% at 5 to 10 years, 91% at 10 to 15 and 89% at greater than 15 years. There was no difference in pregnancy rates (89%, 82% or 86%) at obstructive intervals of 0 to 5, 5 to 10 or 10 to 15 years, respectively. Pregnancy rates were significantly lower (44%, p <0.05) with obstructive intervals greater than 15 years. Men with at least unilateral sperm granuloma had patency of 95% vs 78% without granulomas, a trend which did not quite reach statistical significance (p = 0.07). There was no difference in pregnancy rates with or without granulomas.

CONCLUSIONS

Vasectomy reversal patency rates are high regardless of time since vasectomy. Pregnancy rates are lower more than 15 years after vasectomy. Sperm granuloma had a favorable impact on patency. Our data indicate that for obstructive intervals less than 15 years vasectomy reversal yields much higher pregnancy rates than in vitro fertilization and intracytoplasmic sperm injection, and that even for intervals greater than 15 years reversal outcomes equal or exceed those of in vitro fertilization and intracytoplasmic sperm injection.

Angiotensin II Dependent Testicular Fibrosis and Effects on Spermatogenesis After Vasectomy in the Rat

PURPOSE

Vasectomy induces testicular interstitial fibrosis in time dependent fashion and inhibits spermatogenesis. We investigated the contribution of angiotensin II (Ang II) to the development of interstitial fibrosis after vasectomy.

MATERIALS AND METHODS

Bilateral vasectomy was performed in 8-week-old Wistar rats and the testes were harvested 1 to 24 weeks after vasectomy. Interstitial fibrosis was evaluated by Masson's trichrome staining. Western blotting and immunohistochemistry were done to examine the expressions of heat shock protein 47 (HSP47), HNE (4-hydroxy-2,3-nonenal) and transforming growth factor-beta1 (TGF-beta1). The antioxidative agent N-acetylcysteine (NAC), the Ang II type 1 receptor antagonist losartan or the Ang converting enzyme inhibitor enalapril was given orally for 24 weeks to vasectomized rats. Spermatogenesis was evaluated by testicular weight and the percent of haploid cells was analyzed by flow cytometry.

RESULTS

Vasectomy significantly increased interstitial fibrosis (more than 8 weeks) and induced the expression of HSP47, HNE modified protein and TGF-beta1. TGF-beta1 and HSP47 immunoreactivity was localized to Leydig cells and fibroblasts. NAC or losartan but not enalapril inhibited the expression of these molecules induced by vasectomy. Increased interstitial fibrosis and impaired spermatogenesis were partially abrogated by NAC or losartan administration.

CONCLUSIONS

There is Ang II type 1 receptor dependent fibrosis after vasectomy. Oxidative condition is considered to trigger and promote these fibrogenic processes. Ang II contributes to the regulation of intratesticular autocrine or paracrine functions after vasectomy.

Vasectomy and the risk of prostate cancer: a meta-analysis examining vasectomy status, age at vasectomy, and time since vasectomy

The aim of this study was to conduct a quantitative review of prostate cancer studies to pool relative risk (RR) estimates on the association between prostate cancer and vasectomy, in an attempt to determine whether there is an association, and if so, its magnitude. Random-effects models were examined along with a linear model for time since vasectomy. The pooled RR estimate was 1.37 (95% CI=1.15-1.62) based on five cohort studies and 17 case-control studies. The RR estimate varied by study design with the lowest risk for population-based case-control studies. No difference was seen in risk by age at vasectomy. A linear trend based on the 16 studies reporting time since vasectomy suggested an 10% increase for each additional 10 y or a RR of 1.32 (95% CI=1.17-1.50) for 30 y since vasectomy. When null effects were assumed for the six studies not reporting information, the linear RR for the 22 studies was 1.07 (1.03-1.11) and 1.23 (1.11-1.37) for 10 and 30 y since vasectomy, respectively. These results suggest that men with a prior vasectomy may be at an increased risk of prostate cancer, however, the increase may not be causal since potential bias cannot be discounted. The overall association was small and therefore could be explained by bias. The latency effect shown here for time since vasectomy should be examined further.

Morphometric study of testis of Wistar rat after open-ended vasectomy

The effects on the testis of open-ended vasectomy in the Wistar rat have been assessed morphometrically and evaluated statistically at 1, 4, 12, and 24 weeks after operation, and compared to those in sham-operated controls. The open-ended technique, ie, without ligation of the epididymal end of the cut ductus deferens, allowed drainage of sperm into the spermatic cord. During the period of our study, it did not affect the structure of the testis; although the germinal epithelium, basement membrane, and the stroma and cells of the interstitial space all showed variations when compared to the control group, these were not statistically significant.

Influence of interstitial fibrosis on spermatogenesis after vasectomy and vasovasostomy

This study focused on the testicular interstitial fibrosis after vasectomy and the intraseminiferous status [i.e., Johnsen's score, proliferative cell nuclear antigen (PCNA) expression] following vasectomy reversal. Testicular biopsy specimens from 21 consecutive men were obtained at vasovasostomy. Percent of interstitial fibrosis was determined quantitatively by NIH-image after Masson Trichrome staining. PCNA-labeling index (LI) was calculated on each testis. The associations between the obstructive interval and each parameter were examined. These parameters were also analyzed on whether patency or pregnancy was achieved or not. Significant decrease in PCNA-LI and increase in interstitial fibrosis were observed along with the obstructive interval (p <0.0001, p = 0.0005, respectively). Interstitial fibrosis of the patients without patency/fertility was significantly greater than that of the patients with patency/fertility (47.5%/39.0% versus 33.4%/32.3%, p = 0.02/0.04, respectively). PCNA-LI and Johnsen's score did not predict the treatment outcome. Interstistial fibrosis, but not the extent of germ cell differentiation or DNA synthesis, reflects the treatment outcome after vasectomy reversal. Interstistial fibrosis contributes to the irreversible damage of vasectomized testes.

Impaired spermatogenesis in men with congenital absence of the vas deferens

It is generally assumed that men with congenital bilateral absence of the vas deferens (CBAVD) have azoospermia because of obstruction and that sperm production is normal. This study examines spermatogenesis in men with CBAVD to assess the validity of this assumption. We identified all men with CBAVD who had undergone either a diagnostic or therapeutic fertility procedure. Procedures included diagnostic biopsy, testis fine needle aspiration (FNA) mapping, microscopic epididymal sperm aspiration (MESA), and testis sperm extraction (TESE). Among 33 CBAVD men, 18 underwent testis biopsy, 27 had MESA/TESE, and 10 had FNA mapping. On evaluation of these procedures, normal spermatogenesis was present in 29 men. Four men (12%) demonstrated impaired spermatogenesis. One patient had FNA testis cytology consistent with late maturation arrest, another demonstrated hypospermatogenesis on biopsy and low sperm yield by MESA, and two patients had pure Sertoli cell only histology on biopsy. Aetiologies for impaired spermatogenesis included varicocele and underlying genetic abnormalities. Although patients with CBAVD are assumed to have normal spermatogenesis and infertility due simply to obstruction, the potential for concomitant defects in sperm production exists. A clinical suspicion of testis failure should prompt further diagnostic evaluation of spermatogenesis prior to sperm retrieval. In addition, genetic counselling should be offered and testing for genetic lesions, including cystic fibrosis gene mutations and/or variants, Y chromosome microdeletions, and karyotype abnormalities, should be considered.

Effect of vasectomy on the seminiferous tubule boundary zone in the Albino Swiss rat

The boundary zone of a seminiferous tubule consists of the basement membrane of the seminiferous epithelium, its myoid cells, and their basal laminae. This study examines the boundary zones of seminiferous tubules in healthy and degenerated testes following long-term, left-sided vasectomy in the rat and compares them to those of sham-operated controls and adult rats exposed in utero to the antiandrogen, flutamide. Degenerated tubular profiles showed similar changes, irrespective of whether the degeneration was ipsilateral or bilateral. In transverse tubular profiles, the basal laminae of the seminiferous epithelium and the myoid cells became more undulating, that of seminiferous epithelium showing complex folding. The collagen layer of the boundary zone, which lies between the basal laminae of the seminiferous epithelium and the myoid cells, thickened and its fibers became irregularly orientated. Rather than being flattened as in controls, the region of the myoid cell near the nucleus and the nucleus itself developed triangular profiles in the transversely sectioned tubules. Similar features were also seen in the degenerated tubules of rats exposed to flutamide. The changes in the boundary zone are not specific for vasectomy and probably reflect reduction in the cross-sectional area of tubular profiles and possibly in their length. We also noted occasional leukocytes infiltrating the boundary zone; they may have increased in number in those tubules that showed degeneration following vasectomy.

Comparison of modified one- and two-layer microsurgical vasovasostomy

OBJECTIVE

To compare the outcome of a modified one-layer and two-layer vasovasotomy (VV) in two groups of similar men undergoing vasectomy reversal.

PATIENTS AND METHODS

The charts and surgical records of all surgical procedures performed on men undergoing a modified one- or two-layer VV between June 1992 and July 1994 were retrospectively reviewed. A successful outcome (patency) was defined as sperm present at follow-up (mean follow-up 8 weeks). A modified one-layer VV was used in 17 men (group 1) and a two-layer VV in 23 (group 2).

RESULTS

Sperm were present in both groups if surgery was undertaken after vasal obstruction lasting < 36 months. The modified one- and two-layer VV had equal patency (88% and 90%, respectively) when undertaken after an obstructed interval of 36-96 months; outcomes were poorer if surgery was performed after > 96 months. The mean operative duration was 96 min for a modified one-layer VV and 167 min for the two-layer VV.

CONCLUSIONS

The simpler and faster modified one-layer VV provides sufficient accuracy for successful vasectomy reversal in most cases. For most patients, both procedures have equivalent patency.

Safety and effectiveness of vasectomy

OBJECTIVE

To recommend further research on vasectomy based on a systematic review of the effectiveness and safety of vasectomy.

DESIGN

A systematic MEDLINE review of the literature on the safety and effectiveness of vasectomy between 1964 and 1998.

MAIN OUTCOME MEASURE(S)

Early failure rates are <1%; however, effectiveness and complications vary with experience of surgeons and surgical technique. Early complications, including hematoma, infection, sperm granulomas, epididymitis-orchitis, and congestive epididymitis, occur in 1%-6% of men undergoing vasectomy. Incidence of epididymal pain is poorly documented. Animal and human data indicate that vasectomy does not increase atherosclerosis and that increases in circulating immune complexes after vasectomy are transient in men with vasectomies. The weight of the evidence regarding prostate and testicular cancer suggests that men with vasectomy are not at increased risk of these cancers.

CONCLUSION(S)

Publications to date continue to support the conclusion that vasectomy is a highly effective form of contraception. Future studies should include evaluations of the long-term effectiveness of vasectomy, evaluating criteria for postvasectomy discontinuation of alternative contraception for use in settings where semen analysis is not practical, and characterizing complications including chronic epididymal pain syndrome.

Degenerated tubules in the guinea pig testis after long-term vasectomy or sham operation

The testes of eight unilaterally vasectomized and six sham-operated Dunkin Hartley guinea pigs were examined 3 years after operation by wax and resin histology and transmission electron microscopy. Degenerated tubules are reported that were common on the side of vasectomy but also found in the contralateral testes and in the controls. A central accumulation of macrophages, rich in phagocytosed debris including spermatozoal fragments, was surrounded by attenuated Sertoli cells, a markedly thickened basement membrane and myoid cells. At some sites macrophages impinged directly on the basement membrane. They probably represented highly degenerated seminiferous tubules. The study suggests that the response to injury of seminiferous tubules may show species variations. Macrophages did not feature in the degenerated seminiferous tubules we reported following vasectomy in the rat. However, the rat showed striking changes in the morphology of the basal laminae and myoid cells which did not occur in the guinea pig. Pathological changes have been reported in the human testis following vasectomy but their etiology is unclear. Studies in the guinea pig are enhancing understanding of the mechanisms and features of testicular damage.

Testicular biopsy in patients with obstructive azoospermia

The present report studies the testicular biopsy lesions (histologic and semiquantitative) in a series of 48 patients with obstructive azoospermia of known etiology (vasectomy, congenital absence of vas deferens, herniorrhaphy, hydrocelectomy, Young's syndrome, and ejaculatory duct obstruction) in order to establish objective testicular data that permit the pathologist to diagnose an obstructive process, which should not be mistaken with a primary testicular lesion. The semiquantitative study included determinations of the average numbers of spermatogonia, primary spermatocytes, young spermatids (Sa + Sb), and differentiated spermatids (Sc + Sd). According to this study, the testes were classified into the following groups: (1) normal testes whose germ cell numbers were within normal limits (27 testes); (2) testes with lesions in the adluminal compartment; these lesions comprise two subgroups: (2a) late sloughing of primary spermatocytes (both spermatid types were greatly reduced in number while the other germ cell types were in normal numbers) (45 testes); and (2b) early sloughing of primary spermatocytes (normal spermatogonial number, reduced number of spermatocytes, and scanty spermatids) (9 testes); and (3) lesions in the basal compartment; these lesions comprise two subgroups: (3a) pure hypospermatogenesis (a proportionate decrease in the numbers of all germ cell types) (8 testes); and (3b) hypospermatogenesis associated with sloughing of primary spermatocytes (decreased numbers of all germ cell types with a very scanty number spermatids) (4 testes). Two testes appeared hyalinized and one testis was removed owing to cryptorchidism. The most frequent testicular lesion observed (alteration in the adluminal compartment of seminiferous tubules) seems to be related to the increase in hydrostatic pressure in the tight compartment formed by seminiferous tubules, rete testis, efferent ducts, the epididymal duct, and the initial portion of the vas deferens. The severity of the lesions is probably related to the cause and span of the obstruction. In addition, two azoospermic men without obstructive azoospermia and whose testicular biopsy study revealed meiotic anomalies (with the subsequent bad prognosis) were also studied for comparison. The semiquantitative study of these patients permitted the differential diagnosis between two lesion types. Testes with meiotic anomalies had a disproportionately elevated number of primary spermatocytes, and an extremely low number of young spermatids.

Sperm mitochondria-associated cysteine-rich protein (SMCP) is an autoantigen in Lewis rats

A common repertoire of rat sperm antigens have previously been identified by Western blotting of sperm proteins with sera obtained after vasectomy or isoimmunization with sperm. Aside from a determination of their apparent masses, however, the biochemical characteristics of these antigens have remained unknown. In this study, a rat testis cDNA expression library was screened with polyclonal antibodies obtained from rats immunized with isologous spermatozoa to identify and sequence a full-length clone encoding rat sperm mitochondria-associated cysteine-rich protein (SMCP). The open reading frame of SMCP was expressed in the pET22b vector, and recombinant SMCP (rec-SMCP) was purified. Sera from rats that had been vasectomized or hyperimmunized with isologous sperm specifically recognized rec-SMCP whereas preimmune sera from these experimental groups did not react. Rabbit antiserum produced to rec-SMCP recognized rec-SMCP on Western blots and precisely immunolocalized SMCP to the mid-piece of rat sperm. On Western blots against sperm extracts, the rabbit antibody recognized a major protein band of approximately 22-25 kDa that co-migrated with bands of identical mass that were recognized by sera from hyperimmune or vasectomized rats. These findings demonstrate that SMCP is a sperm autoantigen, recognized following vasectomy, and an isoantigen, recognized by antibodies generated through isologous immunization with sperm.

Degeneration of the seminiferous epithelium following epididymal obstruction in prepubertal rats

The development of the testes was studied in rats following prepubertal obstruction of the epididymis. Male rats received bilateral ligation of the corpus epididymidis or a sham operation at 10 days of age, and temporal changes in testicular morphology and weights of reproductive organs were determined at intervals spanning sexual maturation. Development of the testes was normal through 35 days of age. The initial histological changes in the testes of ligated animals, observed at 56 days, included an increased diameter of the seminiferous tubule lumen, depletion of spermatids, and the presence of multinucleate spermatids. Subsequently, germ cells were greatly depleted in the testes of 91- and 128-day-old rats with ligated epididymides. After puberty, testicular weight and volume declined relative to corresponding sham-operated animals. On the other hand, the weights of the epididymides in ligated animals prior to puberty significantly exceeded those of sham-operated rats but weighed significantly less than those of rats in the sham group after sexual maturation. Testicular alterations occurred after increases in the weights of the epididymides. Testicular changes may have contributed to rather than resulted from an autoimmune response to spermatozoa because testicular alterations preceded increases in antisperm autoantibodies.