The Association Between Testicular Microlithiasis and Semen Parameters in Chinese Adult Men With Fertility Intention: Experience of 226 Cases

Is testicular microlithiasis associated with decreased semen parameters? a systematic review

BACKGROUND

Testicular microlithiasis (TM) is characterised by microcalcifications in the testes and has been associated with infertility. This has led to studies of semen analysis in men with the condition. This systematic review aimed to compare semen parameters in men with TM and those without. Men with classic TM (≥ 5 microcalcifications per sonographic image) were also compared to those with limited TM (< 5 microcalcifications per sonographic image). Additionally, testicular volume and hormone levels were analysed as secondary outcomes. This review was carried out according to PRISMA guidelines and registered on PROSPERO. The quality of included studies was assessed using the Newcastle-Ottawa Scale.

RESULTS

Embase, MEDLINE, World of Science and Scopus were searched. Abstracts were screened against inclusion/exclusion criteria by two independent reviewers. Eligible studies included data on semen parameters in men with TM where semen analysis was done according to World Health Organisation recommendations. Studies with populations consisting of men with testicular cancer were excluded. After searching the databases, 137 papers were found and 10 studies involving 611 men with TM were included in the analysis. In the studies that compared sperm concentration in men with TM to controls, six (100%) found lower sperm concentration in the TM group. Six studies compared sperm motility, of which 4 (66.7%) showed lower motility in the TM group compared to controls. Five studies compared sperm morphology, with three (60%) finding a lower percentage of normal morphology in the TM group compared to controls. Six studies compared classic TM with limited TM. All six (100%) found a lower sperm concentration in the classic TM group compared to the limited TM group. Results also suggested that more extensive disease is associated with poorer sperm concentration.

CONCLUSIONS

This review suggests that TM is associated with decreased semen parameters, particularly sperm concentration. However, clinical outcomes should be investigated by studying pregnancy rates in males with TM. Future research that controls for confounding variables, involves larger sample sizes, and utilises advanced sperm function tests is also advised. Further research is important for establishing clinical guidance and suggestions for fertility follow-up in men with TM.

Increased serum creatinine associated with testicular microlithiasis in adult Japanese men: A retrospective cohort study

BACKGROUND

Testicular microlithiasis (TM) is thought to be associated with testicular tumors and impaired spermatogenesis; however, its etiology remains unclear.

OBJECTIVES

To identify factors, other than testicular function, that are associated with testicular microlithiasis.

MATERIALS AND METHODS

We enrolled males who underwent ultrasound examination of the scrotum at Tokyo Dental College Ichikawa General Hospital. The patients were categorized into two groups: those with or those without testicular microlithiasis. Background and blood test data were compared between the groups.

RESULTS

Testicular microlithiasis was observed in 72 of the 828 (8.7%) patients enrolled. Ages ranged from 15 to 87 years (mean age, 40.0 years). A history of germ cell tumor was significantly more prevalent in patients with testicular microlithiasis than in those without (1.3 vs. 16.7%; p < 0.001). Blood test data showed that, patients with testicular microlithiasis had significantly higher serum creatinine levels (0.91 vs. 1.04 mg/dL; p = 0.046) and lower calcium levels (9.4 vs. 9.3 mg/dL; p = 0.031) than those without. Serum creatinine levels (> 1.00 mg/dL) and germ cell tumors were significantly associated with testicular microlithiasis in both univariate and multivariate analyses. The prevalence of testicular microlithiasis increased in patients older than 50 years. Age (> 50 years) was associated with testicular microlithiasis in univariate analysis. The mean body weight tended to be heavier (70.7 vs. 72.2 kg; p = 0.051) and epididymitis was observed more frequently (3.2 vs. 8.3%; p = 0.056) in patients with testicular microlithiasis than in those without.

DISCUSSION AND CONCLUSION

A history of testicular tumors and elevated serum creatinine levels were associated with testicular microlithiasis. Testicular microlithiasis was observed across all age groups, with a tendency to increase in patients older than 50 years. Patients with testicular microlithiasis were slightly heavier and had a higher prevalence of epididymitis than those without. Our findings suggest that, in addition to testicular dysgenesis, other factors are involved in the development of testicular microlithiasis.

Infertility risk assessment with ultrasound in congenital adrenal hyperplasia male patients

Testicular adrenal rest tumor (TART) is a prevalent complication associated with congenital adrenal hyperplasia (CAH), culminating in gonadal dysfunction and infertility. Early hormonal intervention is preventive, but excessive glucocorticoid poses risks. Developing reliable methods for early TART diagnosis and monitoring is crucial. The present study aims to formulate a scoring system to identify high-risk infertility through analysis of TART ultrasound features. Grayscale and power Doppler ultrasound were employed in this retrospective study to evaluate testicular lesions in male CAH patients. Lesion assessment encompassed parameters such as range, echogenicity, and blood flow, and these were subsequently correlated with semen parameters. Results of 49 semen analyzes from 35 patients demonstrated a notable inverse correlation between lesion scores and both sperm concentration (rs = - 0.83, P < 0.001) and progressive motility (rs = - 0.56, P < 0.001). The ROC curve areas for evaluating oligospermia and asthenozoospermia were calculated as 0.94 and 0.72, respectively. Establishing a lesion score threshold of 6 revealed a sensitivity of 75.00% and specificity of 93.94% for oligospermia and a sensitivity of 53.85% and specificity of 100.00% for asthenozoospermia. These findings underscore the potential utility of incorporating ultrasound into routine CAH patient management, facilitating timely interventions to preserve male fertility.

"Dancing Coins?" Unexpected Finding During microsurgery and Potential Risk of Sperm Damage: Intrascrotal Calculi: A Retrospective Analysis

Objective

Microsurgery of andrology always brings unexpected findings. Scrotal calculi are rare and unique, which are easily confused with tumor. To understand its etiology and harm, our study retrospectively analyzed the clinical characteristics of men with scrotal calculi to provide a reference for clinical practice.

Methods

The clinical data of patients who underwent microscopic testicular sperm extraction (MTESE) and microscopic epididymal sperm aspiration (MESA) from January 1, 2018 to December 31, 2021 were retrospectively analyzed. Data screening was performed on cases in which calculi were found or not, and the relationship between calculi and spermatogenesis was analyzed.

Results

A total of 405 patients were recruited. After screening, 218 nonobstructive azoospermia (NOA), 83 obstructive azoospermia (OA), and 13 cryptozoospermia (CZ) patients were included in the study. Calculi were found in 3 patients [incidence was 0.74% (3/405)], in which 2 patients had obstructive azoospermia (1 was epididymal calculi, 1 was intrascrotal calculi) and 1 patient had cryptozoospermia (intrascrotal calculi). Pathological results showed that chronic granuloma with abscess infiltration appeared in epididymal tissue, basement membrane thickening and fibrosis appeared in seminiferous tubules, and fibrous hyperplasia with calcium deposition was found in scrotal calculus. White blood cells, lymphocytes, red blood cells, abstinence time and urethritis were closely related to the occurrence of calculi. While abstinence time might be a potential predictor, which increased the risk by approximately 1.2 times.

Conclusion

Disturbance of the testicular microenvironment caused by lymphocyte infiltration may be the main reason for scrotal calculi and ultimately cause spermatogenesis disorders. Prolonged sexual abstinence was a potential risk.

Functional histology of human scrotal wall layers and their overlooked relation with infertility: a narrative review

Male infertility currently contributes to nearly half of the reported infertility cases. Scrotal wall layers play a cardinal role in regulating testicular physiology. However, few studies have focused on the functional histology of these layers and their relations with infertility in humans. The objective of the present narrative review is to collate novel insights into the functional histology of the human scrotal wall layers and their relation with infertility. The data was extracted from articles published between 1946 and 2021. The study was performed between January and December 2021. 71 original studies have been included in this review. Despite the fact that few studies have presented detailed functional histology of the human scrotal wall layers, this narrative review elucidates the possible influence of scrotal histology on infertility. Scrotal wall layers-associated pathologies may induce infertility by various mechanisms. They can impose mechanical forces that may affect the testicular histology and stimulate testicular inflammation. Moreover, they may induce testicular hyperthermia. Various unanswered clinical questions have been identified in this narrative review. More clinical studies are needed to assess the effect of alterations in the components of the scrotal wall layers on fertility (e.g., due to the exposure to metabolic and/or psychological stressors). In addition, testing the effectiveness of various pharmacological/surgical interventions to treat scrotal wall layers-associated pathologies will provide more insights into infertility treatment.

The prognostic value of testicular microlithiasis as an incidental finding for the risk of testicular malignancy in children and the adult population: A systematic review. On behalf of the EAU pediatric urology guidelines panel

INTRODUCTION

The exact correlation of testicular microlithiasis (TM) with benign and malignant conditions remains unknown, especially in the paediatric population. The potential association of TM with testicular malignancy in adulthood has led to controversy regarding management and follow-up.

OBJECTIVE

To determine the prognostic importance of TM in children in correlation to the risk of testicular malignancy or infertility and compare the differences between the paediatric and adult population.

STUDY DESIGN

We performed a literature review of the Medline, Embase and Cochrane controlled trials databases until November 2020 according to the Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) Statement. Twenty-six publications were included in the analysis.

RESULTS

During the follow-up of 595 children with TM only one patient with TM developed a testicular malignancy during puberty. In the other 594 no testicular malignancy was found, even in the presence of risk factors. In the adult population, an increased risk for testicular malignancy in the presence of TM was found in patients with history of cryptorchidism (6% vs 0%), testicular malignancy (22% vs 2%) or sub/infertility (11-23% vs 1.7%) compared to TM-free. The difference between paediatric and adult population might be explained by the short duration of follow-up, varying between six months and three years. With an average age at inclusion of 10 years and testicular malignancies are expected to develop from puberty on, testicular malignancies might not yet have developed.

CONCLUSION

TM is a common incidental finding that does not seem to be associated with testicular malignancy during childhood, but in the presence of risk factors is associated with testicular malignancy in the adult population. Routine monthly self-examination of the testes is recommended in children with contributing risk factors from puberty onwards. When TM is still present during transition to adulthood a more intensive follow-up could be considered.

Historical trends for the standards in scrotal ultrasonography: What was, what is and what will be normal

BACKGROUND

Ultrasonography is the gold standard imaging method for scrotal investigation. Colour Doppler ultrasonography, contrast-enhanced ultrasonography and sonoelastography allow sonographers to assess size, echotexture, vascular features and stiffness of the scrotal organs and abnormalities. Scrotal ultrasonography has been used to investigate male reproductive health, scrotal pain, masses and trauma. However, ultrasonography thresholds/classifications used to distinguish normal and pathologic features of the scrotal organs have changed over time, and have not yet been fully standardized.

OBJECTIVES

To evaluate historical trends for the standards in scrotal ultrasonography: what was, what is and what will be normal.

METHODS

An extensive Medline search was performed identifying the most relevant studies in the English language from inception to date.

RESULTS

We provide here (i) a brief overview of the history of ultrasonography, (ii) current indications for scrotal ultrasonography and (iii) previous and current normal values, cut-offs and classifications of the main colour-Doppler ultrasonography parameters/characteristics of the scrotal organs, as derived from recent guidelines and evidence-based studies. In addition, we report recommendations and the clinical utility of contrast-enhanced ultrasonography and sonoelastography. Finally, we discuss critical issues needing further evidence and future directions to fill in the current gaps.

DISCUSSION

Several studies on scrotal ultrasonography are available. However, guidelines/recommendations dealing with specific ultrasonography applications have been published only in recent years. More recently, the European Academy of Andrology published evidence-based scrotal colour-Doppler ultrasonography reference ranges/normative parameters derived from a cohort of healthy, fertile men. In addition, a standardization of the methodology to evaluate qualitative and quantitative colour-Doppler ultrasonography parameters was reported. Other international societies reported indications, methodological standards, clinical utility and limitations of contrast-enhanced ultrasonography and sonoelastography.

CONCLUSIONS

To date, colour-Doppler ultrasonography normative values for the scrotal organs are available. However, a wide international consensus on assessment and classification of several ultrasonography parameters is still lacking. An alignment of the world societies on these issues is advocated.

Clinical and seminal parameters associated with testicular microlithiasis and its severity in males from infertile couples

STUDY QUESTION

Is there an association of testicular microlithiasis (TM) and its severity with testicular dysfunction in men from infertile couples?

SUMMARY ANSWER

The presence of ≥5 testis microcalcifications per sonogram at the scrotal ultrasonography (US) of infertile males was associated with a more severe testicular dysfunction as compared to males with limited, or without, TM.

WHAT IS KNOWN ALREADY

TM, representing an incidental finding in the scrotal US, is associated with male infertility and a higher risk for testicular cancer as compared to that in infertile males without TM. Still, there are unresolved questions on the relation between TM severity and testicular dysfunction in infertile men, as well as on the identification of risk factors for TM.

STUDY DESIGN, SIZE, DURATION

This study was an observational, retrospective, case-control investigation involving males who underwent clinical evaluation, measurement of reproductive hormones, seminal analysis and scrotal US as part of diagnostic work-up for couple infertility at an andrology clinic, between January 2004 and December 2018. One hundred patients, out of the 2112 scored men, were found to have TM during the US evaluation. One hundred male partners from 100 infertile couples without TM, comprising the control group, were selected through a matched analysis by age and date of evaluation to reduce the confounding effect of both age and technique variability all along the long period of observation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

TM was defined as limited TM (LTM) or classical TM (CTM), when the maximum number of hyperecogenic spots per sonogram was &lt;5 or ≥5, respectively. CTM, LTM and control groups were compared for clinical variables, serum levels of FSH, LH, and total testosterone, as well for semen parameters and scrotal US features.

MAIN RESULTS AND THE ROLE OF CHANCE

After the exclusion of cases with testicular nodules to eliminate the possible confounding effect of testis cancer on testicular dysfunction, cases with CTM showed a lower mean testis volume (P = 0.03) and a lower sperm concentration (P = 0.03) as compared to the other two groups. A higher FSH level was observed in the CTM group compared to the LTM group (P = 0.02) and in controls (P = 0.009). The multiple logistic regression analysis showed that only a smaller testicle volume exhibited an independent significant association with a higher odds of detecting CTM (odds ratio = 0.84, 95% CI: 0.75–0.94; P = 0.02). No significant differences were observed between groups in the prevalence of risk factors for testicular cancer, or in the prevalence of conditions associated with TM.

LIMITATIONS, REASONS FOR CAUTION

The retrospective design of the study did not allow conclusions to be drawn about the possible underlying links in the associations of TM with defective spermatogenesis.

WIDER IMPLICATIONS OF THE FINDINGS

Males from infertile couples who exhibit a reduced testicular volume should undergo scrotal US, independent of sperm parameters, to exclude CTM and, eventually, testis cancer, although the association of CTM and current or future testis cancer risk is not yet clear. Evidence is provided here demonstrating that the presence of LTM has no clinical relevance in males from infertile couples.

STUDY FUNDING/COMPETING INTEREST(S)

Investigation was funded by Ministero dell’Università e della Ricerca, PRIN 2018, Italy. The authors have not declared any competing interests.

TRIAL REGISTRATION NUMBER

N/A

Prevalence of testicular microlithiasis in healthy newlywed men trying for first-time pregnancy

OBJECTIVES

To investigate the prevalence of testicular microlithiasis and the relationship between testicular microlithiasis, semen parameters and endocrinological profiles in healthy newlywed men trying for first-time pregnancy.

METHODS

Men visiting Juntendo University Urayasu Hospital, Urayasu, Chiba, Japan, or D Clinic Tokyo, Chiyoda-ku, Tokyo, Japan, for a first-time examination of fertility underwent scrotal examination, semen analysis and blood tests. Testicular volume measured by orchidometer, semen parameters measured by the Makler counting chamber and endocrinological profiles were compared between men with testicular microlithiasis and without testicular microlithiasis. The correlation between sperm concentration and the number of calcifications, and sperm motility and the number of calcifications, were investigated.

RESULTS

Of 739 men, 60 (8.1%) were diagnosed as having testicular microlithiasis. Among them, testicular volume, semen volume and motility were lower than those in the men without testicular microlithiasis. Luteinizing hormone and follicle-stimulating hormone levels were higher in those with than those without testicular microlithiasis. The sperm concentration correlated negatively with the number of calcifications. There was no significant correlation between sperm motility and the number of calcifications.

CONCLUSION

Herein, we report the prevalence of testicular microlithiasis in healthy newlywed men. Furthermore, our findings suggest that semen parameters in men with severe testicular microlithiasis tend to be worse.

Testicular microlithiasis on scrotal ultrasound in 4850 young men from the general population: associations with semen quality

BACKGROUND

Testicular microlithiasis (TM) is sometimes found on scrotal ultrasound. The prevalence seems higher in populations of men with testicular dysfunction, and TM may be a risk factor for testicular germ cell neoplasia in situ in men with additional risk factors. The association between TM and testicular function is controversial, especially in incidentally found TM.

OBJECTIVES

To determine the frequency of TM in young men from the general population, and associations between TM, semen quality, and reproductive hormones.

MATERIALS AND METHODS

A cross-sectional study of 4850 Danish men, median age 19 years. Testicular pattern, including the presence of TM, was assessed by ultrasound examination. Participants provided a questionnaire, one semen sample, and one blood sample. Semen variables and serum reproductive hormones were analyzed as outcomes using multivariable regression analysis to determine associations with TM.

RESULTS

TM was detected in 53 men (1%), of which 19 (36%) were unilateral and 34 (64%) were bilateral cases. A history of cryptorchidism was associated with presence of TM. Bilateral TM was associated with slightly lower testicular volume, sperm concentration, and total sperm count. TM was not significantly associated with serum testosterone or other reproductive hormones.

DISCUSSION AND CONCLUSION

TM is rare in men from the general population and is associated with lower sperm count if bilateral, although effect sizes were small. Current European guidelines do not recommend any follow-up in cases of TM with no other risk factors for testicular cancer. We suggest that men with incidentally found bilateral TM may be offered a semen analysis, but analysis of reproductive hormones seems unnecessary.

Scrotal ultrasonographic findings in obese infertile patients and their correlations to semen and hormonal profile

OBJECTIVE

The aim of this prospective study was to compare scrotal ultrasonographic findings in obese and normal weight infertile men and correlate these findings with semen parameters and hormonal profile.

MATERIAL AND METHODS

A total of 188 men presented for infertility evaluation were included in this study. They were divided according to body mass indices into obese (n=96) and normal weight infertile patients (n=92). Basic infertility evaluation, semen analysis and scrotal duplex ultrasound examination in addition to measurement of serum levels of follicular stimulating hormone, testosterone and estradiol were done for all cases. The ratio between testicular size measured by scrotal ultrasound and body mass index were calculated.

RESULTS

Any significant differences were not observed in semen parameters, serum levels of follicular stimulating hormone and testosterone between obese and normal weight infertile men (p>0.05). Serum estradiol level was significantly higher in obese than normal weight infertile men (p<0.001). There is significant increase in subclinical varicocele, hydrocele and testicular microlithiasis detected by scrotal ultrasound in obese infertile men than nonobese patients (p<0.05). Despite having comparable testicular size detected on scrotal ultrasound, infertile obese men had significantly lower total testicular volume to body mass index ratio and this ratio correlated positively with semen volume, sperm concentration, total sperm count and serum testosterone but negatively with serum follicular stimulating hormone and estradiol levels.

CONCLUSION

We therefore conclude that the incidence of subclinical varicocele, hydrocele and testicular microlithiasis was higher in obese infertile patients and the ratio between testicular volume assessed by scrotal ultrasound and body mass index may be a new parameter that correlates with subfertility status in these men.

Testicular microlithiasis: what urologists should know. A review of the current literature

Introduction

Testicular microlithiasis is a finding incidental to the ultrasound examination of the scrotum. This article presents some new data regarding the etiopathology of testicular microliths. As there is a growing body of literature available, which associates testicular microlithiasis with a testicular germ cell tumor or male infertility, our review focuses on these relations (based on a new meta-analysis and retrospective follow-up programs). The purpose of this review is to summarize the knowledge about testicular microlithiasis and discuss the latest recommendations.

Material and methods

A comprehensive literature review was performed using Science Direct and Scopus with MeSH terms and keywords 'testicular microlithiasis', testicular tumor', male infertility'.

Results

The clinical consequences of testicular microlithiasis depend on the co-occurrence of specific risk factors. The presence of testicular microlithiasis alone in the absence of risk factors is not an indication for further investigation.

Conclusions

A link between testicular microlithiasis and testicular cancer as well as male infertility has been analyzed. Follow-up is only recommended where risk factors of testicular cancer other than testicular microlithiasis are present.

Prevalence and risk factors of testicular microlithiasis in patients with hypospadias: a retrospective study

BACKGROUND

It has been described that the incidence of testicular microlithiasis is high in several congenital disorders which may be associated with testicular impairment and infertility. Several reports have shown that a prepubertal or pubertal hormonal abnormality in the pituitary-gonadal axis was identified in some patients with hypospadias that is one of the most common disorders of sex development. However, exact prevalence or risk factors of testicular microlithiasis in patients with hypospadias have not reported so far. In the present study, to clarify the prevalence and risk factors of testicular microlithiasis in patients with hypospadias, a retrospective chart review was performed.

METHODS

Children with hypospadias who underwent testicular ultrasonography between January 2010 and April 2016 were enrolled in the present study. Severity of hypospadias was divided into mild and severe. The prevalence and risk factors of testicular microlithiasis or classic testicular microlithiasis were examined.

RESULTS

Of 121 children, mild and severe hypospadias were identified in 66 and 55, respectively. Sixteen children had undescended testis. Median age at ultrasonography evaluation was 1.7 years old. Testicular microlithiasis and classic testicular microlithiasis were documented in 17 children (14.0%) and 8 (6.6%), respectively. Logistic regression analysis revealed that presence of undescended testis was only a significant factor for testicular microlithiasis and classic testicular microlithiasis. The prevalence of testicular microlithiasis or classic testicular microlithiasis was significantly higher in children with undescended testis compared to those without undescended testis (testicular microlithiasis; 43.8% versus 9.5% (p = 0.002), classic testicular microlithiasis; 37.5% versus 1.9% (p < 0.001).

CONCLUSIONS

The current study demonstrated that the presence of undescended testis was only a significant risk factor for testicular microlithiasis or classic testicular microlithiasis in patients with hypospadias. As co-existing undescended testis has been reported as a risk factor for testicular dysfunction among patients with hypospadias, the current findings suggest that testicular microlithiasis in children with hypospadias may be associated with impaired testicular function. Conversely, patients with isolated HS seem to have lower risks for testicular impairment. Further investigation with longer follow-up will be needed to clarify these findings.

Role of calcifying nanoparticles in the development of testicular microlithiasis in vivo

BACKGROUND

Calcifying nanoparticles (NPs) have been proven to be associated with a variety of pathological calcification and previously detected in semen samples from patients with testicular microlithiasis (TM). The present study was designed to test the hypothesis if human-derived NPs could invade the seminiferous tubules and induce TM phenotype.

METHODS

The animals were divided into three groups. Normal saline (0.2 mL) was injected into the proximal right ductus deferens in group A as a control group. The experimental groups, B and C received Escherichia coli (10⁶ cfu/mL, 0.2 mL) and human-derived NPs suspension (0.2 mL), respectively. Rats were euthanized in 2 batches at 2 and 4 weeks. Testicular pathology, ultrastructure and inflammatory mediators were assessed.

RESULTS

Chronic inflammatory changes were observed at 2 weeks in both groups B and C. Moreover, the innermost layer of sperm cells were structurally impaired and a zone of concentrically layered collagen fibers around the human NPs body was formed in the lumen of the seminiferous tubule in group C only, in which TM phenotype of remarkable calcification surrounded by cellular debris within the seminiferous tubules was built at 4 weeks.

CONCLUSIONS

The results obtained from our study suggested a potential pathogenic effect of NPs in the development of calcification within the seminiferous tubules, which should be addressed in the future studies.

The influence of testicular microlithiasis on the outcomes of in vitro fertilisation in a Chinese Han population

To investigate the influence of testicular microlithiasis (TM) on the outcomes of in vitro fertilisation (IVF), we retrospectively reviewed the ultrasonography results of the TM patients who underwent IVF treatment in our hospital. They were classified as classic-TM (CTM) or limited-TM (LTM) comparing with patients without TM (Non-TM). Semen parameters, rates of fertilisation, normal fertilisation, good embryos and clinical pregnancy were analysed. The Non-TM group showed higher percentage of morphologically normal spermatozoa than the CTM or LTM group (4.08 ± 2.07 versus 3.40 ± 2.00 versus 3.04 ± 1.66, p = .003) while the other general semen parameters were comparable. The LTM group showed higher rate of fertilisation than the CTM group (85.10% versus 81.12%, p = .044). Moreover, the rates of normal fertilisation of Non-TM (62.47%) and LTM (66.32%) group were significantly higher than the CTM (58.02%) group (p = .027 and p = .001 respectively). There were 333 embryo transfer cycles in total (including 222 fresh and 111 frozen). The overall clinical pregnancy rate was 54.95%, 58.33% and 64.12% in the group of CTM, LTM and Non-TM respectively. However, no statistically significant difference was obtained (p = .326). Our results suggest that TM may have influence on the IVF outcomes. The extent of microlithiasis correlates inversely with the rates of fertilisation and normal fertilisation.

Management of non-obstructive azoospermia

Non-obstructive azoospermia (NOA) is defined as no sperm in the ejaculate due to failure of spermatogenesis and is the most severe form of male infertility. The etiology of NOA is either intrinsic testicular impairment or inadequate gonadotropin production. Chromosomal or genetic abnormalities should be evaluated because there is a relatively high incidence compared with the normal population. Although rare, NOA due to inadequate gonadotropin production is a condition in which fertility can be improved by medical treatment. In contrast, there is no treatment that can restore spermatogenesis in the majority of NOA patients. Consequently, testicular extraction of sperm under an operating microscope (micro-TESE) has been the first-line treatment for these patients. Other treatment options include varicocelectomy for NOA patients with a palpable varicocele and orchidopexy if undescended testes are diagnosed after adulthood, although management of these patients remains controversial. Advances in retrieving spermatozoa more efficiently by micro-TESE have been made during the past decade. In addition, recent advances in biotechnology have raised the possibility of using germ cells produced from stem cells in the future. This review presents current knowledge about the etiology, diagnosis, and treatment of NOA.