Paternity after bilateral cryptorchidism. A controlled study

Male infertility

Clinical infertility is the inability of a couple to conceive after 12 months of trying. Male factors are estimated to contribute to 30-50% of cases of infertility. Infertility or reduced fertility can result from testicular dysfunction, endocrinopathies, lifestyle factors (such as tobacco and obesity), congenital anatomical factors, gonadotoxic exposures and ageing, among others. The evaluation of male infertility includes detailed history taking, focused physical examination and selective laboratory testing, including semen analysis. Treatments include lifestyle optimization, empirical or targeted medical therapy as well as surgical therapies that lead to measurable improvement in fertility. Although male infertility is recognized as a disease with effects on quality of life for both members of the infertile couple, fewer data exist on specific quantification and impact compared with other health-related conditions.

Azoospermic Men with a History of Cryptorchidism Treated by Orchiopexy Have Favorable Outcomes after Testicular Sperm Extraction: A Systematic Review and Meta-Analysis

PURPOSE

This systematic review and meta-analysis investigated the sperm retrieval rate (SRR) and pregnancy rate after testicular sperm extraction in men with azoospermia and those with a history of cryptorchidism treated by orchiopexy.

MATERIALS AND METHODS

The SRR and clinical pregnancy rate were investigated. We performed a sub-analysis that included factors such as bilaterality, age, and idiopathic non-obstructive azoospermia (iNOA). The analysis comprised 13 studies from January 1995 to July 2021. The data sources were PubMed/MEDLINE, Embase, and the Cochrane Library included "cryptorchidism", "orchidopexy", "azoospermia", and "testicular sperm extraction".

RESULTS

The overall mean SRR was 63.3% (95% confidence interval [CI], 57.6%-68.6%; I²=62.4%), and the overall mean clinical pregnancy rate was 30.1% (95% CI, 22.6%-38.8%; I²=69.9%). The meta-analysis comparing the SRR, there was no significant difference between patients with a history of bilateral and unilateral orchiopexy (relative risk [RR]=1.02; 95% CI, 0.89-1.16; p=0.79). Orchiopexy performed under the age of 10 years showed significantly increased SRR compared to the age of over 10 years (RR=1.25; 95% CI, 1.06-1.47; p=0.008). Azoospermic men with a history of cryptorchidism treated by orchiopexy had significantly higher SRR than iNOA (RR=1.90; 95% CI, 1.40-2.58; p<0.0001).

CONCLUSIONS

Men with azoospermia and a history of cryptorchidism treated by orchiopexy had significantly higher SRR than those with iNOA after testicular sperm extraction. Furthermore, patients who underwent orchiopexy before the age of ten years had significantly higher SRR than patients operated at an older than the age of ten years.

Loss of WNT4 in the gubernaculum causes unilateral cryptorchidism and fertility defects

Undescended testis (UDT) affects 6% of male births. Despite surgical correction, some men with unilateral UDT may experience infertility with the contralateral descended testis (CDT) showing no A-dark spermatogonia. To improve our understanding of the etiology of infertility in UDT, we generated a novel murine model of left unilateral UDT. Gubernaculum-specific Wnt4 knockout (KO) mice (Wnt4-cKO) were generated using retinoic acid receptor β2-cre mice and were found to have a smaller left-unilateral UDT. Wnt4-cKO mice with abdominal UDT had an increase in serum follicle-stimulating hormone and luteinizing hormone and an absence of germ cells in the undescended testicle. Wnt4-cKO mice with inguinal UDT had normal hormonal profiles, and 50% of these mice had no sperm in the left epididymis. Wnt4-cKO mice had fertility defects and produced 52% fewer litters and 78% fewer pups than control mice. Wnt4-cKO testes demonstrated increased expression of estrogen receptor α and SOX9, upregulation of female gonadal genes, and a decrease in male gonadal genes in both CDT and UDT. Several WNT4 variants were identified in boys with UDT. The presence of UDT and fertility defects in Wnt4-cKO mice highlights the crucial role of WNT4 in testicular development.

The role of laparoscopy in non-palpable undescended testicle: Analysis and review of the experience from two cities in Sudan

INTRODUCTION

It is estimated that 1%-2% of male infants have undescended testicles. The reliability of ultrasound (US) to identify the non-palpable undescended testicles (NPUDT) is controversial. Laparoscopy remains the gold standard to diagnose and manage NPUDT.

OBJECTIVE

The objective is to highlight the role of laparoscopy in the management of NPUDT in 2 cities from Sudan over the past decade.

MATERIALS AND METHODS

Patients presented to Gadarif Teaching Hospital and Almak Nimir University Hospital with NPUDT were assessed by clinical examination and US. The testis, when found during laparoscopy, was either brought down to the scrotum in a single or two-stage or removed depending on the findings. Data were collected and analysed.

RESULTS

Patients covered the age range between 18 months and 65 years. The average was 12.4. The majority, 94 (67.2%) patients were older than 5 years. The main presenting symptom was either bilateral or unilateral empty scrotum. In 12 (8.4%) patients, the main presenting symptom was primary infertility. US was done in 120 (86.6%) of the patients and failed to see the testis in more than half of them. A single-stage procedure in the form of laparoscopic search assisted with orchidopexy was achieved in 90 (62.9%) patients and orchiectomy in 13 (9.1%) patients, while in 12 (8.4%) patients the testis was not found. Other procedures were applied on the 28 (19.6%) patients who needed staged operation in the form of Fowler Stephen's, in bilateral cases, in 6 (4.2%) patients. Shehata's operation in nine patients (64%) and open orchidopexy for 8 (5.6%) patients. The post-operative complication was encountered in 14 (9.8%) of the patients in this group in the form of bleeding, vassal injury and testicular atrophy.

CONCLUSION

Laparoscopy provides the most accurate interventional option for managing patients with NPUDT. Laparoscopic orchidopexy, whether single stage for low or 2-stages for high intra-abdominal testis, is a proven and effective extension of lap-search with minimal complications.

European Association of Urology Guidelines on Male Sexual and Reproductive Health: 2021 Update on Male Infertility

CONTEXT

The European Association of Urology (EAU) has updated its guidelines on sexual and reproductive health for 2021.

OBJECTIVE

To present a summary of the 2021 version of the EAU guidelines on sexual and reproductive health, including advances and areas of controversy in male infertility.

EVIDENCE ACQUISITION

The panel performed a comprehensive literature review of novel data up to January 2021. The guidelines were updated and a strength rating for each recommendation was included that was based either on a systematic review of the literature or consensus opinion from the expert panel, where applicable.

EVIDENCE SYNTHESIS

The male partner in infertile couples should undergo a comprehensive urological assessment to identify and treat any modifiable risk factors causing fertility impairment. Infertile men are at a higher risk of harbouring and developing other diseases including malignancy and cardiovascular disease and should be screened for potential modifiable risk factors, such as hypogonadism. Sperm DNA fragmentation testing has emerged as a novel biomarker that can identify infertile men and provide information on the outcomes from assisted reproductive techniques. The role of hormone stimulation therapy in hypergonadotropic hypogonadal or eugonadal patients is controversial and is not recommended outside of clinical trials. Furthermore, there is insufficient evidence to support the widespread use of other empirical treatments and surgical interventions in clinical practice (such as antioxidants and surgical sperm retrieval in men without azoospermia). There is low-quality evidence to support the routine use of testicular fine-needle mapping as an alternative diagnostic and predictive tool before testicular sperm extraction (TESE) in men with nonobstructive azoospermia (NOA), and either conventional or microdissection TESE remains the surgical modality of choice for men with NOA.

CONCLUSIONS

All infertile men should undergo a comprehensive urological assessment to identify and treat any modifiable risk factors. Increasing data indicate that infertile men are at higher risk of cardiovascular mortality and of developing cancers and should be screened and counselled accordingly. There is low-quality evidence supporting the use of empirical treatments and interventions currently used in clinical practice; the efficacy of these therapies needs to be validated in large-scale randomised controlled trials.

PATIENT SUMMARY

Approximately 50% of infertility will be due to problems with the male partner. Therefore, all infertile men should be assessed by a specialist with the expertise to not only help optimise their fertility but also because they are at higher risk of developing cardiovascular disease and cancer long term and therefore require appropriate counselling and management. There are many treatments and interventions for male infertility that have not been validated in high-quality studies and caution should be applied to their use in routine clinical practice.

Minipuberty: Why Does it Happen?

Minipuberty describes the transient sex-specific activation of the hypothalamic-pituitary-gonadal (HPG) axis during the first 6 months of life in boys and during the first 2 years in girls. It leads to a rise of luteinizing hormone, follicle-stimulating hormone, estradiol, and testosterone. The existence of minipuberty has been known for >40 years, but we still do not fully understand why it takes place. Current thinking suggests that it is an essential imprinting period for different body functions. Firstly, minipuberty plays an important role in genital organ development; testosterone influences penile growth, the number of Sertoli cells, and spermatogenesis. Secondly, it seems to influence the infant's body composition; testosterone likely has an imprinting effect on BMI and body weight of boys and growth velocity in the first 6 months of life. Thirdly, it affects cognitive functions; testosterone has an impact on language organization in the infant brain and estradiol affects laryngeal sound production and baby babbling. There are inconsistent findings concerning the impact of minipuberty on sex-specific playing behavior. Minipuberty is an interesting field of research, and further studies in this area will teach us more about this exciting period of human development.

Fertility potential in adult men treated for uncorrected bilateral cryptorchidism: A systematic literature review and analysis of case reports

OBJECTIVE

Reports of adult orchidopexy for bilateral undescended testicles (bUDT) are sparse, and fertility outcomes are not well established. Our aim was to determine prognosis for restoration of spermatogenesis among adult men (≥18 years) undergoing orchidopexy for bUDT.

METHODS

A systematic literature review, conforming to the PRISMA statement, was conducted using the PubMed/MEDLINE and EMBASE databases through March 2020 using search terms "adult" AND "bilateral orchidopexy" OR "bilateral cryptorchidism." Relevant referenced articles from non-indexed journal were identified by Google Scholar search and additionally included.

RESULTS

Fifty-seven publications including adult men with uncorrected bilateral UDTs were identified. Baseline semen analysis was reported in 157 men, all of whom demonstrated azoospermia. Testosterone values were reported in 82 cases and were normal in 89%. Germ cells could not be identified in 72.6% of histologic specimens from 62 testicles. Abdominal testicles more frequently lacked germ cells (90%, p = 0.038) on univariate analysis. Eleven cases identified ejaculated spermatozoa following adult bilateral orchidopexy (8 publications). Sperm extraction (TESE) during orchidopexy or orchiectomy was reported in 13 men without success. Delayed TESE (median 10 months) was performed in 22 persistently azoospermic men with success in 10 (45.5%), none of whom had abdominal testicles prior to orchidopexy. Six men experienced successful paternity via natural conception (3) or assisted reproduction (3).

CONCLUSION

Fertility is possible in adult men with inguinal bUDT following orchidopexy. Subsequent sperm retrieval may involve ejaculated specimens or delayed TESE. TESE performed prior to or at time of orchidopexy is unlikely to be of benefit.

Male factor infertility trends throughout the last 10 years: Report from a tertiary-referral academic andrology centre

BACKGROUND

Trends of male factor causes of couples' infertility over time have been poorly investigated.

OBJECTIVE

We investigated trends in the causes of pure male factor infertility (MFI) throughout the last 10 years in a tertiary-referral academic andrology center.

MATERIAL AND METHODS

Baseline characteristics at first presentation from a cohort of 1647 consecutive male factor infertility patients belonging to primary infertile couples between 2008 and 2018 have been comprehensively collected over time. Seven major causes of male factor infertility were identified: varicocoele; history of cryptorchidism; hypogonadism (primary and secondary); obstructive azoospermia; genetic abnormalities; other causes (large group including the remnant conditions of known causes); and idiopathic infertility. Rates of different male factor infertility causes over the study period were analyzed. Multivariable logistic regression models tested the likelihood of male factor infertility causes over time. Estimated trends were explored graphically.

RESULTS

Of all, varicocoele was found in 615 (37.3%), cryptorchidism in 124 (7.5%), genetic abnormalities in 61 (3.7%), hypogonadism in 165 (10%), obstructive conditions in 55 (3.3%), other causes in 129 (7.8%) patients, and idiopathic infertility in 498 (30.3%) patients, respectively. Over time, a reduction in the proportions of cryptorchidism and varicocoele (all P < 0.001) cases was observed, along with an increase in the proportions of hypogonadism, other causes of MFI and idiopathic cases (all P ≤ 0.01). Rates of genetic and obstructive cases remained stable. The observed trends were confirmed at logistic regression models.

DISCUSSION AND CONCLUSIONS

A decreasing trend in the proportions of varicocoele and cryptorchidism at first presentation was observed over the last 10 years; conversely, the proportions of idiopathic cases, hypogonadal patients, and infertile men presenting with other male factor infertility causes significantly increased over the same time frame at a single tertiary-referral academic andrology center.

Fertility induction in hypogonadotropic hypogonadal men

Men with hypogonadotropic hypogonadism (HH) are typically azoospermic, and yet HH is one of the few treatable forms of male infertility. Sperm induction protocols using gonadotrophins aim to replicate the natural endocrine control of spermatogenesis. Previously virilised men with adult-onset HH and normal testicular volume respond well to monotherapy in which human chorionic gonadotrophin (hCG) acts as a long-acting LH-analogue stimulating spermatogenesis. However, this approach is rarely successful for men with congenital HH (CHH) (eg, Kallmann syndrome), for whom combined gonadotrophin therapy (hCG + follicle-stimulating hormone [FSH]) is an absolute requirement to maximise fertility potential. Key baseline predictors of successful spermatogenesis-induction include prior spontaneous testicular development (ie, testicular volume [TV] > 4 mL), serum inhibin B (I_B ) concentration >60 pg/mL and no history of maldescended testes (cryptorchidism).

Clinical Consultation Guide on Imaging in Male Infertility and Sexual dysfunction

Imaging can benefit clinicians in evaluating men with infertility or sexual dysfunction by giving an overview of a patient's overall clinical condition before undertaking an invasive procedure. An understanding of the limitations and advantages of image modalities used in clinical practice will ensure that clinicians can optimize patient care with imaging when necessary. PATIENT SUMMARY: The objective of this article was to review the current literature on imaging modalities used for the diagnosis and management of male infertility and sexual dysfunction. An understanding of the advantages and limitations of these imaging modalities will ensure that clinicians can optimize patient care with imaging when necessary.

Inhibin B in healthy and cryptorchid boys

Background

Cryptorchidism, the most common male genital abnormality observed in paediatrics, might often be associated with long-term functional consequences and can even reoccur after a successful orchidopexy. Serum markers that identify cryptorchid boys with gonadal dysfunction early should be useful in a decision-making process. Inhibin B, produced during all of childhood but altered in cryptorchid subjects, appears strictly related to Sertoli cells, and its levels directly reflect the status of the testis germinative epithelium. Unfortunately, its precise roles in bilateral and unilateral cryptorchidism are still debated and being unravelled. Herein, we report the most current knowledge about inhibin B in both healthy boys and those with cryptorchidism to discuss and clarify its potential clinical applications.

Discussion

Inhibin B represents a simple and repeatable serum marker and it seems to well asses the presence and function of the testicular tissue. Testicular tissue in prepubertal age is largely made up of Sertoli cells; inhibin B, coming from working Sertoli cells, allows to indirectly evaluate their function. Besides, inhibin B is produced throughout childhood, even before puberty, in contrast with central hormones, and it is not influenced by androgens during puberty, in contrast with other testicular hormones. Although further studies are needed, low levels of inhibin B have been related with low testicular score and/or with consistent alterations of testicular parameters at histological examination. This means that inhibin B could be an indirect marker of testicular functions that could even replace testicular biopsies, but current data are inconsistent to confirm this potential role of inhibin B in cryptorchidism.

Conclusion

Inhibin B represents an effective candidate for early identification of testicular dysfunction after orchidopexy for cryptorchidism. Unfortunately, current data cannot exactly clarify the real role of inhibin B as a predictor of future testicular function in cryptorchidism and future long-term follow-up studies, with repeated inhibin B checks both in cryptorchid and in formerly cryptorchid children and adolescents, will permit to assess if previous normal levels of inhibin B would match with future normal pubertal development and fertility potential.

Sperm DNA damage measured by sperm chromatin structure assay in men with a history of undescended testes

The aim of this study was to compare sperm DNA damage between men with a history of congenital undescended testis (UDT) and men with a history of acquired UDT. A long-term follow-up study of men with previous UDT was performed. Fifty men with congenital UDT who had undergone orchiopexy at childhood age, 49 men with acquired UDT after a 'wait-and-see'-protocol (e.g. awaiting spontaneous descent until puberty and perform an orchiopexy in case of non-decent), and 22 healthy proven fertile men were included. The DNA fragmentation index (DFI) using sperm chromatin structure assay (SCSA) was used to express the level of sperm DNA damage. Decreased fertility potential was considered if DFI was above 30%. Sperm DNA damage was not statistically different between cases of congenital and acquired UDT. DFI was significantly more often >30% in the complete group of men with congenital UDT (9/50; 18%) and in the subgroup with bilateral congenital UDT (3/7; 43%) in comparison with the controls (none) (p-value 0.049 and 0.01, respectively). Age at orchiopexy in congenital UDT had no statistical effect on DNA damage. In men with acquired UDT, DFI did not statistically differ between those having undergone orchiopexy and those experiencing spontaneous descent. This study supports the hypothesis that UDT is a spectrum representing both congenital UDT and acquired UDT. Sperm DNA damage at adult age is not influenced by age at orchiopexy in congenital UDT cases and by orchiopexy or spontaneous descent in acquired UDT cases.

Delayed treatment of undescended testes may promote hypogonadism and infertility

CONTEXT

Undescended testes at birth may be caused by testosterone deficiency during fetal development. It is unclear whether the process of failed descent contributes to permanent endocrine impairment.

OBJECTIVES

To evaluate the impact of age at treatment of undescended testes on endocrine and spermatogenic testicular function in middle-aged men.

PATIENTS AND METHODS

Reproductive hormone and semen data of 357 men with previously undescended testes were evaluated with respect to age at correction of testicular position and compared to those of 709 controls with eutopic testes at birth and normozoospermia.

RESULTS

Men with undescended testes had higher mean Luteinizing Hormone levels (p < 0.0001) and lower mean testosterone levels (p = 0.003) compared to controls. They also had lower bi-testicular volumes, higher Follicle Stimulating Hormone levels, and lower sperm concentrations (all p < 0.0001). Lowest mean sperm concentrations were found in subjects with bilateral undescended testes. Normal sperm concentrations were found in 21 % of cases (in 27 % of men with unilateral and in 12 % with bilateral undescended testes), while oligozoospermia was diagnosed in 44 %, and azoospermia in 35 % (in 28 % with unilateral, 46 % with bilateral undescended testes). Subjects with reduced semen quality had higher gonadotropin levels than those with normozoospermia. Age at correction (median: 6 years (1-39)) was inversely correlated with bi-testicular volumes and sperm concentrations, and positively correlated with FSH and LH, but not with serum testosterone.

CONCLUSION

Latent, rarely decompensated hypogonadism is a potential long-term consequence of undescended testes, besides infertility and testicular cancer, preferentially affecting subjects with delayed or unsuccessful correction of testicular position. Impaired Leydig cell function is likely to contribute to compromised fertility. These observations support correction of cryptorchidism during early infancy.

Selective use of laparoscopy in nonpalpable undescended testes

Introduction:

Approximately, 20% of undescended testes (UDT) are nonpalpable. Surgical management of the nonpalpable testis comprises laparoscopy. The aim of this study was to determine if ultrasonography can be used as a preoperative tool to localize the nonpalpable inguinal testis, eliminating the need for laparoscopy.

Methods:

We identified 46 patients diagnosed with nonpalpable UDT between 2007 and 2012 who underwent an inguino-scrotal ultrasound preoperatively. We analyzed correlations between radiological and surgical findings.

Results:

A total of 46 patients (53 UDT), median age 14 months (quartile 1^st: 7; 3^rd: 80) were included. Ultrasound localized the testis as intracanalicular in 24/53 (45.2%), intraabdominal in 10/53 (18.8%), scrotal in 1/53 (1.8%), and could not localize 18/53 (33.9%) testes. In 35/53 (66%) testes, the ultrasound location correlated with the surgical findings (P < 0.001). Ultrasound detection showed 96% sensitivity and 56% specificity for intracanalicular testes.

Conclusion:

The use of preoperative ultrasound in this series was helpful in identifying the location of nonpalpable testes in children. In particular, the ultrasound finding of an intracanalicular testis may preclude the need for laparoscopy.

Undescended testis and infertility-Is hormonal therapy indicated?

PURPOSE

The purpose of this chapter is to review hormonal therapy in cryptorchidism in boys to improve fertility.

METHODS

Multiple searches, primarily in PubMed, were performed using various combinations of the terms: cryptorchidism, undescended testis (UDT), hormonal therapy, fertility, infertility, germ cell numbers, spermatogonia and semen analyses. In additions the pertinent articles from the reference lists in these papers were also obtained and reviewed.

RESULTS

Data on fertility in unilateral cryptorchidism does not reveal a significant risk for infertility. Testes biopsies in childhood do not correlate with fertility parameters in adulthood. In bilateral cryptorchidism there is a significant risk of infertility. Results of hormonal treatment were not reported separately for bilateral cryptorchidism. Current data is insufficient to know if hormonal therapy is efficacious in bilateral UDT.

CONCLUSIONS

Hormonal therapy should not be used in childhood to improve fertility in cases of unilateral cryptorchidism. Testes biopsies in childhood to identify those at risk for infertility should not be performed in unilateral cryptorchidism. More data are needed to answer whether hormonal therapy is beneficial in bilateral UDT. There is insufficient data to establish that testis biopsies are helpful in bilateral cryptorchidism in identifying the subgroup with risk for infertility. They should not be performed in the routine clinical setting but may have a role in a research protocol.

Effects on normalized testicular atrophy index (TAIn) in cryptorchid infants treated with GnRHa pre and post-operative vs surgery alone: a prospective randomized trial and long-term follow-up on 62 cases

PURPOSE

The aim of this study was to investigate the effects of gonadotropin releasing hormone analog (GnRHa) therapy on normalized testicular atrophy index (TAIn) using gonadorelin before and after orchiopexy.

METHODS

62 infants with 87 undescended testes (UDT) were prospectively assigned to two homogeneous groups according to age, position of UDT and TAIn. The patients were randomized to receive either orchiopexy alone or orchiopexy combined with GnRHa as nasal spray at 1.2 mg daily for 4 weeks before surgery and 4 weeks after surgery. Surgical approaches were relative to the position of the UDT: Shoemakers technique in proximal-UDT and Bianchi technique in distal-UDT. All the patients were evaluated clinically and sonographically 1 month before surgery, at the time of surgery, 1 month, 6 months and 5 years after surgery.

RESULTS

Ultrasound data in our study have shown a statistically significant decrease of TAIn in children given additional HT only after 5 years of follow-up, in unilateral cases and in the entirety of treated patients; in bilateral cases this difference was not statistically significant.

CONCLUSION

Patients with a TAIn >20% treated with preoperative and post-operative GnRHa therapy have a significant increase in testicular volume after 5 years of follow-up, as shown by the relative reduction of TAIn values.

Fertility potential in a cohort of 65 men with previously acquired undescended testes

PURPOSE

To evaluate testicular function in men with previously acquired undescended testes (AUDT) in whom spontaneous descent was awaited until puberty followed by orchiopexy in case of nondescent.

METHODS

Andrological evaluation including paternity, scrotal ultrasound, reproductive hormones, and semen analysis was performed in three groups: men with AUDT, healthy controls, and men with previously congenital undescended testes (CUDT).

RESULTS

In comparison with controls, men with AUDT more often had significantly abnormal testicular consistency, smaller testes, lower sperm concentration, and less motile sperm. Except for more often a normal testicular consistency in men with AUDT, no differences were found between men with AUDT and men with CUDT. Also, no differences were found between men with AUDT which had spontaneously descended and men who underwent orchiopexy.

CONCLUSIONS

Fertility potential in men with AUDT is compromised in comparison with healthy controls, but comparable with men with CUDT. This suggests that congenital and acquired UDT share the same etiology. No significant difference was found between men who had spontaneous descent and men needing orchiopexy. However, fertility potential is unknown for men after immediate surgery at diagnosis, and this should be a subject for future studies.

Gonocyte transformation to spermatogonial stem cells occurs earlier in patients with undervirilisation syndromes

AIM

Fertility post-orchidopexy is dependent on transformation of neonatal gonocytes (G) into adult dark spermatogonia at about 3 months, the same time as gonadotrophins stimulate androgen secretion. We examined how androgen blockade affects transformation of gonocytes to spermatogonial stem cells (SSC) during this period in patients with undervirilisation syndromes.

METHODS

Patients with undervirilisation syndromes (n=30, 1.5 weeks-16 years) underwent review of medical records, pathology reports, and H&E slides of testes (ethics HREC32164). Fluorescent immunohistochemistry against anti-Mullerian hormone (AMH, Sertoli cells), mouse VASA homologue (MVH, germ cells) and DAPI (nuclei) allowed the number of MVH-positive gonocytes/spermatogonial stem cells per seminiferous tubular cross-section (G/T or SSC/T) to be counted.

RESULTS

Gonocytes (MVH-positive cells in the tubular lumen) were present in 15/16 patients under 2 years old. SSC (MVH-positive cells on the tubule basement membrane) were present in 25/30 patients. With increasing age, the mean number of SSC/T decreased from ~4 to 0, and G/T decreased from ~1.5 to 0. SSC were present in CAIS and PAIS patients at 1.5 and 3.5 weeks old, respectively.

CONCLUSIONS

Gonocytes transform into SSC earlier than expected in patients with undervirilisation syndromes. Lack of androgens may stimulate non-androgenic regulators to trigger transformation. Understanding how gonocytes transform may enable optimization of spermatogonial development to preserve fertility post-orchidopexy.

Cryptorchidism

PURPOSE OF REVIEW

Cryptorchidism remains a major cause of male infertility and can be associated with germ cell tumors. Recent reports regarding cause, diagnosis, treatment and outcome of this disorder continue to inform our understanding of this common and important problem. The frequency of the problem makes cryptorchidism an area where diagnostic knowledge is particularly important for healthcare professionals.

RECENT FINDINGS

The literature reviewed in this article approach cryptorchidism from multiple aspects. Reports regarding cause include studies of molecular genetics, endocrine chemical disruptors, the association with galactosemia, the association with low birth weight, and for acquired cryptorchidism, the relationship to infant feeding. In regard to treatment, the benefit of surgical repair at 9 months of age and compliance with recommendations is demonstrated. Further reports continue to document the cryptorchidism's negative impact on fertility, the higher risk of future gonadal malignancy and the lack of function of the unrepaired unilateral cryptorchid testis in adulthood. Management considerations such as the benefit of testicular biopsy at orchiopexy are also reviewed. It was concluded from an analysis of data from the Danish national registry that this can be a valid research tool for future evaluation of the outcome after cryptorchidism.

SUMMARY

Early recognition and surgery, before 1 year of age, remain the most important interventions to reduce the negative impact of both unilateral and bilateral cryptorchidism. Further research is needed to better understand causes of cryptorchidism and the mechanisms by which it exerts its negative effects and to clarify outcome factors to direct the best clinical management of cryptorchidism.

Diagnostic imaging in cryptorchidism: utility, indications, and effectiveness

BACKGROUND

Cryptorchidism (undescended testis) is the most common genitourinary anomaly in male infants.

METHODS

We reviewed the available literature on the diagnostic performance of ultrasound, computed tomography, and magnetic resonance imaging (MRI) in localizing undescended testes.

RESULTS

Ultrasound is the most heavily used imaging modality to evaluate undescended testes. Ultrasound has variable ability to detect palpable testes and has an estimated sensitivity and specificity of 45% and 78%, respectively, to accurately localize nonpalpable testes. Given the poor ability to localize nonpalpable testes, ultrasound has no role in the routine evaluation of boys with cryptorchidism. Magnetic resonance imaging has greater sensitivity and specificity but is expensive, not universally available, and often requires sedation for effective studies of pediatric patients. Diagnostic laparoscopy has nearly 100% sensitivity and specificity for localizing nonpalpable testes and allows for concurrent surgical correction.

CONCLUSIONS

Although diagnostic imaging does not have a role in the routine evaluation of boys with cryptorchidism, there are clinical scenarios in which imaging is necessary. Children with ambiguous genitalia or hypospadias and undescended testes should have ultrasound evaluation to detect the presence of müllerian structures.

Male factor assessment in infertility

Male infertility assessment is more than a semen analysis. By interpreting a semen analysis, clinicians recognize its uses and limitations. Once understood, clinicians can then apply modern techniques of endocrine and radiologic evaluation to diagnosis of male reproductive dysfunction. It is important to identify patients with infertility not only to allow reproductive potential but also to identify a population susceptible to future disease states.

Diagnostic performance of ultrasound in nonpalpable cryptorchidism: a systematic review and meta-analysis

CONTEXT

Ultrasound is frequently obtained during the presurgical evaluation of boys with nonpalpable undescended testes, but its clinical utility is uncertain.

OBJECTIVE

To determine the diagnostic performance of ultrasound in localizing nonpalpable testes in pediatric patients.

METHODS

English-language articles were identified by searching Medline, Embase, and the Cochrane Library. We included studies of subjects younger than 18 years who had preoperative ultrasound evaluation for nonpalpable testes and whose testis position was determined by surgery. Data on testis location determined by ultrasound and surgery were extracted by 2 independent reviewers, from which ultrasound performance characteristics (true-positives, false-positives, false-negatives, and true-negatives) were derived. Meta-analysis of 12 studies (591 testes) was performed by using a random-effects regression model; composite estimates of sensitivity, specificity, and likelihood ratios were calculated.

RESULTS

Ultrasound has a sensitivity of 45% (95% confidence interval [CI]: 29-61) and a specificity of 78% (95% CI: 43-94). The positive and negative likelihood ratios are 1.48 (95% CI: 0.54-4.03) and 0.79 (95% CI: 0.46-1.35), respectively. A positive ultrasound result increases and negative ultrasound result decreases the probability that a nonpalpable testis is located within the abdomen from 55% to 64% and 49%, respectively. Significant heterogeneity limited the precision of these estimates, which was attributable to variability in the reporting of selection criteria, ultrasound methodology, and differences in the proportion of intraabdominal testes.

CONCLUSIONS

Ultrasound does not reliably localize nonpalpable testes and does not rule out an intraabdominal testis. Eliminating the use of ultrasound will not change management of nonpalpable cryptorchidism but will decrease health care expenditures.

Cryptorchidism

Cryptorchidism is a very common anomaly of the male genitalia, affecting 2%-4% of male infants and is more common in premature infants. There are two separate stages of testicular descent. The first stage occurs at 8-15 weeks' gestation in the human fetus and is characterized by enlargement of the genito-inguinal ligament, or gubernaculum, and regression of the cranial suspensory ligament. The testis remains close to the future inguinal region as the fetal abdomen grows. Leydig cells in the testis produce insulin-like hormone 3, which stimulates the caudal gubernaculum to grow and become thicker. Mullerian inhibiting substance may have a role in the first phase of descent by stimulating the swelling reaction in the gubernaculum. The second phase of testicular descent requires migration of the gubernaculum and testis from the inguinal region to the scrotum, between 25 and 35 weeks' gestation. The genitofemoral nerve releases calcitonin gene-related peptide, a neurotransmitter that provides a chemotactic gradient to guide migration. The exact cause of cyrptorchidism remains elusive. Information is mainly derived from animal studies (especially in rodents), which may not extrapolate to the human setting. These findings, however, do have some similarities among mammalian species. The current recommended timing for orchidopexy is between 6 and 12 months of life in an effort to preserve the spermatogonia--the stem cells for subsequent spermatogenesis. Despite surgical treatment by orchidopexy, the long-term outcome still remains problematic and controversial. Impaired fertility (33% in unilateral cases and 66% in bilateral undescended testes) and a cancer risk 5-10 times greater than normal is observed over time. Further research into the cause and management of undescended testes is necessary.

Anomalies postnatales du développement de la spermatogenèse associées aux troubles de la migration testiculaire

La cryptorchidie, testicule non descendu dans sa position normale intrascrotale, est l’une des anomalies congénitales les plus fréquentes du système génital masculin. Le mécanisme de cette migration est un processus complexe encore mal connu. Plusieurs hypothèses étiologiques ont été avancées pour tenter d’expliquer la survenue de la cryptorchidie. L’existence d’une anomalie de la descente testiculaire, même traitée dans l’enfance, est un facteur de risque de cancer du testicule. Mais elle peut aussi se traduire à l’âge adulte par des anomalies des paramètres spermatiques et une atteinte de la fertilité. Dans la présente revue sont rassemblées les données concernant les anomalies du développement postnatal de la spermatogenèse observées en cas de troubles isolés de la migration du testicule et leurs conséquences à l’âge adulte sur les paramètres de la fertilité.

A critical appraisal of the evidence for improved fertility indices in undescended testes after gonadotrophin-releasing hormone therapy and orchidopexy

Male fertility depends on the transformation of gonocytes into dark adult spermatogonia, during the first 3 months of postnatal life, and this is an androgen-dependent process. This essential developmental step appears to be defective in undescended testes, and in many patients orchidopexy alone (at the age it is currently performed) does not improve fertility indices, either because it does not address the underlying pathophysiology or the surgery is performed too late. Hormone therapy with gonadotrophin-releasing hormone creates a rise in testosterone levels, copying the postnatal gonadotrophin surge. This can improve germ cell numbers, with the implication of enhanced longer-term fertility. The role of hormone therapy has been controversial, and although favoured at the European Society of Paediatric Urologists' workshops in 2008 and 2009, it is not routine clinical practice in the UK or other countries. We performed a critical appraisal of the key papers in the world literature to evaluate the level of evidence for improved fertility indices, semen analysis and paternity rates following hormone therapy in undescended testes. We suggest that the evidence is sufficiently strong to recommend a change in clinical practice.

Age at orchiopexy and testis palpability predict germ and Leydig cell loss: clinical predictors of adverse histological features of cryptorchidism

PURPOSE

We determined the relationship between clinical variables and testicular histopathological changes associated with decreased fertility potential in children with cryptorchidism.

MATERIALS AND METHODS

Testis biopsies of 274 children who underwent orchiopexy and concurrent testicular biopsy between 1991 and 2001 were analyzed for germ and Leydig cell loss, and testicular fibrosis. Multivariable logistic regression was used to determine if age at orchiopexy (analyzed as continuous and ordinal variables), preoperative testis palpability, unilateral vs bilateral disease and/or side of undescended testis was predictive of these pathological outcomes.

RESULTS

Age at orchiopexy was associated with germ and Leydig cell depletion. Each month of testis undescent was associated with development of moderate/severe germ cell depletion (OR 1.02 for each month of age, p <0.005) and Leydig cell loss (OR 1.01 for each month of age, p <0.02). Nonpalpable testes were associated with severe germ cell depletion. Children with palpable testes had lower odds of germ cell depletion than those with nonpalpable testes (OR 0.46, p <0.005). This finding corresponds to a significant 2% risk per month of severe germ cell loss and 1% risk per month of Leydig cell depletion for each month a testis remains undescended, and a 50% greater risk of germ cell depletion in nonpalpable relative to palpable cryptorchid testes.

CONCLUSIONS

Testes that remain undescended are associated with progressive loss of germ and Leydig cells, and nonpalpable testes predict severe germ cell loss.

Cryptorchidism and testicular cancer: separating fact from fiction

PURPOSE

We dissected prevailing assumptions about cryptorchidism and reviewed data that support and reject these assumptions.

MATERIALS AND METHODS

Five questions about cryptorchidism and the risk of testicular cancer were identified because of their implications in parent counseling and clinical management. Standard search techniques through MEDLINE were used to identify all relevant English language studies of the questions being examined. Each of the 5 questions was then examined in light of the existing data.

RESULTS

The RR of testicular cancer in a cryptorchidism case is 2.75 to 8. A RR of between 2 and 3 has been noted in patients who undergo orchiopexy by ages 10 to 12 years. Patients who undergo orchiopexy after age 12 years or no orchiopexy are 2 to 6 times as likely to have testicular cancer as those who undergo prepubertal orchiopexy. A contralateral, normally descended testis in a patient with cryptorchidism carries no increased risk of testis cancer. Persistently cryptorchid (inguinal and abdominal) testes are at higher risk for seminoma (74%), while corrected cryptorchid or scrotal testicles that undergo malignant transformation are most likely to become nonseminomatous (63%, p <0.0001), presumably because of a decreased risk of seminoma.

CONCLUSIONS

Orchiectomy may be considered in healthy patients with cryptorchidism who are between ages 12 and 50 years. Observation should be recommended in postpubertal males at significant anesthetic risk and all males older than 50 years. While 5% to 15% of scrotal testicular remnants contain germinal tissue, only 1 case of carcinoma in situ has been reported, suggesting that the risk of malignancy in these remnants is extremely low.

Role of hormones, genes, and environment in human cryptorchidism

Cryptorchidism is the most frequent congenital birth defect in male children (2-4% in full-term male births), and it has the potential to impact the health of the human male. In fact, although it is often considered a mild malformation, it represents the best-characterized risk factor for reduced fertility and testicular cancer. Furthermore, some reports have highlighted a significant increase in the prevalence of cryptorchidism over the last few decades. Etiology of cryptorchidism remains for the most part unknown, and cryptorchidism itself might be considered a complex disease. Major regulators of testicular descent from intraabdominal location into the bottom of the scrotum are the Leydig-cell-derived hormones testosterone and insulin-like factor 3. Research on possible genetic causes of cryptorchidism has increased recently. Abundant animal evidence supports a genetic cause, whereas the genetic contribution to human cryptorchidism is being elucidated only recently. Mutations in the gene for insulin-like factor 3 and its receptor and in the androgen receptor gene have been recognized as causes of cryptorchidism in some cases, but some chromosomal alterations, above all the Klinefelter syndrome, are also frequently involved. Environmental factors acting as endocrine disruptors of testicular descent might also contribute to the etiology of cryptorchidism and its increased incidence in recent years. Furthermore, polymorphisms in different genes have recently been investigated as contributing risk factors for cryptorchidism, alone or by influencing susceptibility to endocrine disruptors. Obviously, the interaction of environmental and genetic factors is fundamental, and many aspects have been clarified only recently.

Assessment of Serum Follicle-Stimulating Hormone Level and Testicular Volume for Prediction of Paternity Potential in Pubertal Boys Who Underwent Bilateral Orchiopexy in Childhood

PURPOSE

We examined infertile adults for the presence of spermatozoa in the testes, serum FSH level and testicular volume to predict paternity potential in pubertal boys who had undergone bilateral orchiopexy in childhood.

MATERIALS AND METHODS

The study included 58 idiopathic infertile men (group 1), 14 infertile men who had undergone bilateral orchiopexy in childhood (group 2) and 21 pubertal boys who had undergone bilateral orchiopexy in childhood (group 3). We evaluated the correlation between FSH level and testicular volume in all groups. In groups 1 and 2 the testes were examined for the presence of spermatozoa using bilateral testicular biopsy samples.

RESULTS

Judging from the presence of spermatozoa in the testes and correlation between FSH level and testicular volume, 14 patients in group 1 (24%) were categorized as being at high risk, 32 (55%) at intermediate risk and 12 (21%) at low risk for loss of paternity potential, with spermatozoa positive rates of 0%, 49% and 100%, respectively. In comparison, 4 patients in group 2 (29%) were categorized as being at high risk, 7 (50%) at intermediate risk and 3 (21%) at low risk, with spermatozoa positive rates of 0%, 43% and 100%, respectively. According to this categorization, 19% of pubertal boys in group 3 were at high risk and may already have lost their paternity potential.

CONCLUSIONS

Despite bilateral orchiopexy in childhood, some male adolescents may not have the potential for paternity.

EFFECT OF EPIDERMAL GROWTH FACTOR ON SPERMATOGENESIS IN THE CRYPTORCHID RAT

PURPOSE

Epidermal growth factor (EGF) is secreted mainly from the submandibular glands. Submandibular gland ablation causes a marked decrease in male fertility, which suggests that EGF influences spermatogenesis. We investigated the effect of EGF in combination with orchiopexy on cryptorchid rat testes in which tubular deterioration had become partially irreversible.

MATERIALS AND METHODS

Unilaterally cryptorchid rats were obtained by daily administration of 7.5 mg flutamide (Nihonkayaku, Tokyo, Japan), an androgen receptor antagonist, to pregnant rats. At age 10 weeks the unilaterally cryptorchid rats underwent orchiopexy with or without EGF administered into the cryptorchid testis. EGF solution (10 microg/ml) was delivered into the seminiferous tubules by retrograde perfusion through the rete testis. At 14 days testicular recovery was assessed based on the maturity of spermatogenesis using a modified Johnsen score and from the number of apoptotic germ cells per seminiferous tubule.

RESULTS

Mean Johnsen score +/- SEM was significantly higher in the orchiopexy with EGF than in the orchiopexy without EGF group (7.85 +/- 0.12 vs 7.12 +/- 0.13, p <0.001). The number of apoptotic germ cells tended to be smaller in the orchiopexy with EGF group than in the orchiopexy without EGF group (0.16 +/- 0.05 vs 0.28 +/- 0.08).

CONCLUSIONS

Although orchiopexy for cryptorchidism partly improved spermatogenesis, recovery was limited. EGF administered in combination with orchiopexy was more effective for spermatogenesis than orchiopexy alone. This may be applicable in patients with cryptorchidism.

Apoptosis and proliferation in human undescended testes

OBJECTIVE

To study apoptosis and proliferation in the testes of children with undescended testes; the degree to which undescended testes contributes to a patient's ultimate fertility is debatable, but undescended testes have fewer germ cells, and some have proposed that apoptosis is an important cause.

PATIENTS AND METHODS

Testis biopsies were taken at the time of orchidopexy in a consecutive series of children undergoing surgical repair for undescended testes. Immunohistological techniques were used to detect apoptosis and proliferation, and the numbers of cells undergoing apoptosis or proliferation per 50 seminiferous tubules were recorded.

RESULTS

Inguinal testes had less apoptosis than abdominal testes, with a mean (sd) of 0.71 (1.31) vs 1.63 (1.95) apoptotic cells per 50 seminiferous tubules (P < 0.02). Similarly, there was less apoptosis in children aged > 1 years than in children aged < 1 years (0.68 (1.40) vs 1.35 (1.56); P < 0.03). Proliferation was very limited in all cryptorchid testes. In contrast to cryptorchid testes, five autopsy controls had many more apoptotic cells, (10.60 (1.34) per 50 seminiferous tubules), and many more proliferating cells, (8.40 (6.43) per 50 seminiferous tubules).

CONCLUSION

In contrast to animal studies, neither apoptosis nor proliferation was common in undescended testes from 6 months of age onward. However, apoptosis was more common in abdominal testes and in children aged < 1 year. It is likely that, if substantial apoptosis occurs in human undescended testes, it occurs before 6 months of age.

Effect of cryptorchidism and retractile testes on male factor infertility: A multicenter, retrospective, chart review

This multicenter retrospective chart review study performed on 162 cryptorchid patients and on 34 subjects with retractile testes suggests that cryptorchidism and retractile testes can alter spermatogenesis, with more serious damage observed in bilateral cryptorchidism. This spermatogenetic impairment is probably related to the lack of an appropriate or timely surgical correction.

Testicular descent, cryptorchidism and inguinal hernia: the Melbourne perspective

Cryptorchidism is the commonest congenital genitourinary anomaly in males and results when the testis does not descend into its normal intrascrotal position during development. In full-term infants, the incidence is approximately 3% at birth. Cryptorchidism results in several abnormalities, including attenuated spermatogenesis, infertility and a greater risk of malignancy. The normal mechanism of testicular descent appears to be multi-staged, with various anatomical factors and hormonal influences, but the exact process is still unclear. In this article we review the current theories of normal testicular descent, with a focus on the hormones and anatomical factors, and current treatments for undescended testis.

Clinical Laboratory Evaluation of Male Subfertility

Male subfertility is a common problem with a complex etiology, requiring a complete andrological work-up for proper diagnosis. The male reproductive tract is controlled by a well-balanced hormonal system, in which hypothalamic (GnRH), pituitary (LH, FSH) and testicular hormones (androgens, inhibin B) participate. Any disturbance of this hormonal system may therefore lead to testicular dysfunction and interfere with the spermatogenesis process. In addition, also other components along the ductal system, such as epididymis, prostate and seminal vesicles, that improve sperm fertility by contributing their secretions to the semen, might function inadequately and thus fail to enhance the fertilizing capacity of the sperm cells. External factors (heat, chemicals, life style) and anatomical abnormalities (varicocele) were shown to have a negative influence on male fertility. In a number of patients genetic defects can be identified as the cause of their infertility. Laboratory tests are available to assess hormone concentrations, semen composition, accessory gland function and sperm cell function. Conventional semen analysis includes the determination of sperm concentration, semen volume, sperm motility (qualitative and quantitative), sperm morphology, sperm cell vitality, pH, leucocytes and antibodies. The usefulness of the determination of these parameters as predictor of fertility appears to be rather limited, however. Therefore, alternative tests, some based on more functional aspects (sperm penetration, capacitation, acrosome reaction), have been developed. Furthermore, there is an increasing attention for the assessment of DNA integrity, for instance by the flowcytometer-based Sperm Chromation Structure Assay (SCSA), as an additional or alternative parameter of sperm quality. It is likely and desirable that further assays with better predictive value are being developed in the near future.

Undescended testes

Undescended testis or cryptorchidism is a common problem encountered in children. Despite the abundant literature on the pathology and management of undescended testis, it is the subject of numerous misgivings and controversies. The article reviews available literature on the entity and their relevance in clinical practice.

The relationship of cryptorchidism to fertility

Cryptorchidism is the most common genitourinary disorder of childhood, resulting in 27,000 surgical cases each year in the United States. Of the 3% of full-term infants affected, most will have testes that will descend normally within a few months. The remaining 1%, who have a cryptorchid condition that persists, should consider medical or surgical intervention. In addition, although the effect of cryptorchidism on testicular development and fertility has been studied extensively, the only fact of certainty is that untreated men with bilateral abdominal testes will be infertile. The remaining scenarios (unilateral, inguinal, gliding, and medically or surgically treated conditions) offer unpredictable levels of fertility. Fortunately, based on recent research, the correlation between testis maldescent and infertility may not be as prevalent as previously reported.

The effect of cryptorchidism on inhibin B in a subfertile population

OBJECTIVE

Prepubertal cryptorchidism may cause fertility problems in adulthood, due to impaired spermatogenesis. Serum inhibin B has emerged as an accurate marker of spermatogenesis. The aim of this study was to evaluate the impact of a history of cryptorchidism on serum inhibin B levels and other markers of spermatogenesis in subfertile men.

PATIENTS AND MEASUREMENTS

In a retrospective study, the effect of cryptorchidism on inhibin B, FSH, LH, free testosterone, testicular volume and semen parameters was assessed in a case-control study within a population of 2613 subfertile men. Of these, 161 and 102 subjects had a history of, respectively, unilateral and bilateral cryptorchidism that was treated by orchiopexy in childhood. Hormone data were complete for 64 cryptorchid patients (32 unilateral and 32 bilateral). A group of 128 patients was randomly selected out of the remaining group of 2350 men with idiopathic subfertility. An additional control group consisted of 32 fertile men from the general population.

RESULTS

In cryptorchid subfertile men, inhibin B concentrations were significantly lower than in noncryptorchid subfertile men and fertile men (103 ng/l, 143 ng/l and 148 ng/l, respectively; P < 0.01). The FSH concentration was significantly higher in cryptorchid men vs. noncryptorchid men and controls (6.1 IU/l vs. 3.3 and 2.9 IU/l, respectively; P < 0.01). Testicular volumes and sperm concentration of cryptorchid men were significantly lower than in noncryptorchid subfertile men (12 vs. 15 ml, P < 0.01 and 3.8 x 10(6) sperm/ml vs. 17.4 x 10(6) sperm/ml; P < 0.05). A significantly higher inhibin B level and sperm concentration was observed in men undergoing orchiopexy at an early age (1-4 years) compared with men treated between 5 and 9 years or later (P < 0.05).

CONCLUSION

Spermatogenesis is more impaired in cryptorchid subfertile men compared to men with idiopathic subfertility, as reflected by a lower inhibin B concentration.

Y chromosome microdeletions in infertile men with cryptorchidism

OBJECTIVE

To determine whether cryptorchidism associated with azoospermia or oligozoospermia may be due to microdeletions of the Y chromosome.

DESIGN

Controlled clinical study.

SETTINGS

Division of Medical Genetics and the Andrology Centre, Department of Obstetrics and Gynecology, University Medical Center, Ljubljana.

PATIENT(S)

Ninety men from infertile couples (36 azoospermics, 35 oligozoospermics, and 19 normozoospermics) with a medical history of cryptorchidism. Nineteen excryptorchid patients with cryptorchidism and Y chromosome microdeletions among 3099 patients from 14 publications.

INTERVENTION(S)

Collection of semen and blood samples.

MAIN OUTCOME MEASURE(S)

Medical history, testicular volume, sperm characteristics, serum FSH levels, testicular histology, presence or absence of Y chromosome microdeletions, including all known Y chromosome genes/gene families in the azoospermia factor (AZF) region.

RESULT(S)

Deletions of the Y chromosome were found in 2 out of 71 cryptorchid patients with azoospermia or oligozoospermia (2.8%). The literature review showed that the incidence of microdeletions in infertile patients with cryptorchidism is lower in comparison with the general population of infertile men (4.9% vs. 8.1%), and that the frequency of cryptorchidism in patients with Y chromosome deletions (6 out of 103, 5.8%) is significantly lower in comparison to infertile patients without deletions (178 out of 1141, 15.6%).

CONCLUSION(S)

No causal relation exists between Y chromosome microdeletions and cryptorchidism.

Update on cryptorchidism: endocrine, environmental and therapeutic aspects

Cryptorchidism is the most frequent developmental abnormality in boys, present in more than 1% of infants above three months of age. It is associated with an increased risk of infertility and testicular cancer. The etiological quest is often disappointing, except in bilateral cases or associated malformations. Recent focus is on genetic and environmental aspects. Animal models have revealed the role of genes encoding for proteins implicated in testicular migration (InsI3, Hoxa 10), but in humans results are less convincing. While some degree of endogenous hormonal abnormality is suspeeted in some patients, the endocrine disruptor hypothesis is also tested. It is unclear whether the incidence of cryptorchidism has really increased, or whether there is only a better screening for this condition. However, other male reproductive problems, such as subfertility, hypospadias and testicular cancer seem on the rise. This secular trend suggests the possible in utero impact of hormonally active environmental factors, such as pesticides with estrogenic or antiandrogenic effect, and is consistent with the increased risk of cryptorchidism observed in the sons of mothers exposed to diethylstilbestrol during pregnancy. From a therapeutic point of view, there is an agreement that the correction of cryptorchidism is needed, but there is controversy on the best medical and/or surgical approach and on the optimal timing. There is a recent trend in proposing early therapeutic intervention, before 1 yr of age, in the hope of improving fertility; however, there is no proof that such a strategy can reduce the risk of testicular cancer.