Unit of Andrology and Reproductive Medicine, Department of Medicine, University of Padova, Padova, Italy.
Linked to ROR, the Research Organization Registry
RRM Academy Synopsis
Infertile men with low sperm counts show more ultrasound abnormalities
Ultrasound problems were more common in 238 men with low or absent sperm counts than in 63 fertile men, in a retrospective study. Scans through the rectum found problems in about 7 out of 10 men with normal follicle-stimulating hormone and about 4 out of 10 with high levels.
Key Findings
Transrectal abnormalities: 69.9% with normal follicle-stimulating hormone versus 38.4% with high levels. Scrotal abnormalities: 60.0% with high levels versus 28.3% with normal levels (both p < 0.01).
Varicocele appeared in 18.6% of men with normal hormone levels and 28.0% of men with high levels, against 7.9% of controls (both p < 0.05).
Smaller bitesticular volume tracked with more abnormal semen parameters (r = –0.248, p < 0.001). A volume below the study's cutoff was associated with higher azoospermia risk (odds ratio = 1.799 [1.255–2.579]).
The area under the curve for counting testicular blood-vessel spots was 0.619 (CI: 0.553–0.684) for sperm count and 0.808 (CI: 0.757–0.859) for follicle-stimulating hormone.
Interpretation
The study analyzed records from one university hospital, with one experienced sonographer performing every scan. The findings are correlations. The outcomes analyzed were semen, hormone, and ultrasound measures. Men with infections, hormonal disorders, or genetic causes were excluded, and controls were fertile men. The authors call the blood-vessel spot count a new measure that is still not standardized. The authors calculated the cutoffs from their own patient group. The authors argue that guidelines should add routine scrotal ultrasound for men with low sperm counts.
RRM Context
Restorative reproductive medicine evaluates both partners. A blocked duct or a structural problem in the man is a diagnosable cause. Infertility with a treatable male cause stays undiagnosed until someone looks. The authors note that major professional societies and the European Academy of Andrology disagree on when scrotal ultrasound belongs in the workup.
Our editorial summary of this paper, not the article's abstract.
Abstract
Background
Scrotal color Doppler ultrasonography and transrectal ultrasonography provide crucial information about the clinical status of testes and male accessory glands.
Objective
To analyze the impact of ultrasound in the evaluation of infertile males.
Materials and Methods
A total of 1120 records from infertile men were retrospectively evaluated (from January 2016 up to June 2020). Data on physical examination, semen analysis, sperm culture, scrotal color Doppler ultrasonography and transrectal ultrasonography, as well as sex hormones were analyzed. Among them, 238 reports from oligozoospermic/azoospermic infertile patients (P) fulfilling the inclusion criteria were considered for data analysis. Patients were subdivided into two groups according to follicle-stimulating hormone (FSH) values (Pa with FSH < 8 U/L and Pb with FSH ≥ 8 U/L). Sixty-three fertile volunteers (mean ± SD years) were enrolled as controls (C).
Results
A higher prevalence of ultrasound abnormalities was recorded in P compared to C. Pb group had significantly lower bitesticular volume compared to Pa and C. Pa had a higher prevalence of transrectal ultrasonography abnormalities than Pb (69.9% vs. 38.4%), whereas Pb had a higher prevalence of abnormalities at scrotal color Doppler ultrasonography (60.0% vs. 28.3%, both p < 0.01). Bitesticular volume was inversely proportional to the number of altered seminal parameters and able to predict gonadotropin levels. A bitesticular volume <17 cc was associated with a higher risk of azoospermia (odds ratio = 1.799). Intratesticular vascularization was inversely correlated with gonadotropin levels and directly correlated with sperm count. A higher prevalence of prostate and seminal vesicle alterations was detected in patients and in Pa group, when compared with Pb group.
Discussion and Conclusions
Ultrasound abnormalities are correlated with seminal parameters and may guide the clinician in the diagnostic workflow of male infertility, suggesting spermatogenesis impairment or genital tract obstructions.
Grande G et al., 2026·The Journal of clinical endocrinology and metabolism·Free to read
Male factor infertility (MFI) is frequently labelled idiopathic when evaluation relies primarily on semen analysis, potentially overlooking endocrine and pathophysiological mechanisms relevant for targeted management.
To phenotypically define MFI and develop a pathophysiology-based classification aimed at reducing idiopathic infertility following comprehensive evaluation.
Prospective monocentric cohort study conducted at a tertiary referral academic centre.
Eight hundred male partners of infertile couples evaluated between October 2024 and January 2026 after exclusion of isolated female factor infertility.
Prevalence of MFI categories, hormonal patterns across phenotypes, and proportion of idiopathic infertility after comprehensive work-up.
All patients underwent standardized clinical evaluation, hormonal assessment (total testosterone, FSH, LH), testicular ultrasound, and complete semen analysis. Microbiological testing, transrectal ultrasound, and genetic analyses were performed according to guidelines.
Primary spermatogenic failure was the most prevalent category (56.0%), followed by infection/inflammation (22.4%) and hypogonadotropic hypogonadism (8.5%). Idiopathic infertility was identified in only 5.3% of cases. Distinct endocrine profiles were observed, with high-FSH spermatogenic failure representing the dominant phenotype.
Comprehensive phenotyping markedly reduces the proportion of patients classified as having idiopathic infertility and identifies clinically relevant subgroups. This prospective study provides validation of a pathophysiology-based classification and supports a shift toward endocrine-integrated diagnostic strategies in male infertility, with potential implications for targeted management.
Rocca MS et al., 2026·Journal of translational medicine·Free to read
Standard semen analysis has little prognostic value in distinguishing fertile from infertile men. Furthermore, in men with semen parameters within the reference ranges, it cannot distinguish fertile men from infertile men, i.e. partners of couples with idiopathic infertility. Oxidative stress, mitochondrial dysfunction, sperm telomere shortening, and DNA fragmentation have been proposed as contributors to impaired male fertility. However, these biomarkers have not been evaluated as a whole in subjects with normal semen parameters, partners of fertile and infertile couples.
To characterise a multidimensional panel of sperm biomarkers-including sperm telomere length (STL), mitochondrial DNA copy number (mtDNAcn), reactive oxygen species (ROS), lipid peroxidation (LP), sperm chromatin dispersion (SCD), and respiratory control ratio (RCR)-and to identify whether these parameters might discriminate, in men with normal semen parameters, infertile men from fertile controls.
A total of 150 men with semen parameters within the normal ranges were enrolled: 47 male partners of couples with idiopathic infertility and 103 fertile controls. STL and mtDNAcn were quantified by qPCR; ROS were assessed using OxiSperm®II with semiquantitative imaging; LP was measured spectrophotometrically in seminal plasma; SCD was used to determine DNA fragmentation; and mitochondrial function was evaluated by oxygen consumption and RCR. Correlations between biomarkers and semen parameters were analysed using Pearson or Spearman coefficients, and intergroup comparisons were adjusted for age.
Semen parameters did not differ significantly between male partners of fertile and infertile couples. compared to men of fertile couples, men of infertile couples exhibited significantly shorter STL (0.57 ± 0.59 vs 1.21 ± 1.13, p_adj = 0.001) and higher oxidative stress, with both ROS (8300.9 ± 4214.8 vs 6555.3 ± 3394.3, p_adj = 0.027) and LP (88.33 ± 55.50 vs 40.29 ± 46.98, p_adj < 0.001) markedly elevated. mtDNAcn, SCD, and RCR showed no difference between the groups. Across the entire cohort, STL correlated negatively with ROS and LP and positively with RCR. ROS correlated negatively with total sperm count, motility and RCR, and positively with LP. LP displayed the strongest pattern of associations, correlating negatively with concentration, total count, motility, STL and RCR, and positively with age and volume.
Among men with normal semen analysis, partners of couples with idiopathic infertility exhibit a distinct sperm molecular profile characterised by telomere shortening and oxidative imbalance. STL, ROS and LP emerged as age-independent biomarkers associated with infertility status and showed promising discriminatory ability in this cohort, supporting their integration as second-level tests to complement routine semen analysis in cases of normozoospermia.
Male Endocrine and Genetic Factors · Genetic Causes of Male Infertility
Genetic variability within the follicle-stimulating hormone (FSH)-related genes might contribute to phenotypic heterogeneity in patients with Klinefelter syndrome (KS), yet its clinical impact on sperm retrieval remains unclear.
To investigate the association between FSHB c.211 G > T and FSHR polymorphisms (c.2039 A > G and c.29 G > A) and hormonal parameters, as well as their potential role in predicting sperm retrieval rate (SRR) in patients with KS undergoing testicular sperm extraction (TESE).
A retrospective cohort of patients with KS was analyzed. Only subjects not receiving testosterone replacement therapy were included (n = 417). Hormonal, anthropometric, and clinical variables were compared across genotypes using nonparametric tests. Additive genetic models were applied to evaluate allele-dose effects. Multivariable logistic regression was performed to identify independent predictors of SRR. Predictive performance of clinical and combined clinical-genetic models was assessed using ROC curve analysis.
FSHB and FSHR genes polymorphisms were associated with variations in serum FSH concentrations, confirming a modulatory role of the FSH-related genes. In additive modeling, the FSHR c.29 G > A polymorphism emerged as an independent predictor of SRR (adjusted OR: 0.29; 95% CI, 0.09-0.97), whereas FSHB c.211 G > T showed a nonsignificant trend. The inclusion of genetic variants modestly improved predictive accuracy compared with clinical variables alone, as demonstrated by ROC analysis.
Genetic variants within the genes involved in FSH action might contribute incremental information for the prediction of sperm retrieval in patients with KS. While the overall predictive gain remains moderate, additive genetic modeling highlights a potential allele-dose effect of FSHR c.29 G > A on reproductive outcome, supporting a role for integrated clinical-genetic assessment in this population, although external validation remains required.
Klinefelter syndrome (KS) is characterized by marked phenotypic heterogeneity that might be influenced by genetic modifiers, including androgen receptor (AR) repeat length (CAGn and GGCn). The clinical relevance of these repeat lengths in patients with KS before testosterone replacement therapy (TRT) remains unclear.
To investigate the association between AR repeat length and anthropometric, hormonal, metabolic, and reproductive parameters in a well-characterized cohort of untreated adult patients with KS.
In this cross-sectional single-center study, 214 men with classical 47, XXY karyotype were evaluated prior to TRT. Clinical, biochemical, and reproductive parameters were analyzed according to AR CAGn and GGCn repeat length. Nonparametric tests, multivariable linear and logistic regression models, and interaction terms between CAGn and GGCn were tested. Standardized beta coefficients were used to compare the relative contribution of AR repeat length with major clinical determinants.
In unadjusted analyses, CAG repeat length was associated with estradiol concentrations, whereas GGC repeat length showed associations with hematocrit, platelet count, and total cholesterol. However, most associations were characterized by small effect sizes and did not persist after multivariable adjustment for possible confounders (age, BMI, and total testosterone levels). Moreover, AR repeat length was not associated with sperm retrieval rate. Standardized beta analyses demonstrated that testosterone levels, BMI, and age accounted for the largest proportion of phenotypic variability, whereas CAGn and GGCn repeat length had minimal roles.
In untreated patients with KS, AR repeat length (CAGn and GGCn) appears to have a limited clinical impact compared with classical endocrine and metabolic determinants. These findings suggest that phenotypic variability in KS might be primarily driven by chromosomal aneuploidy and primary testicular dysfunction rather than AR repeat length.
Foresta C et al., 1998·Human reproduction (Oxford, England)
Azoospermia frequently represents the end-point of different pathological conditions that cause important quantitative and qualitative alterations of both spermatogenesis and testicular structure, including intratesticular blood vessels. In this study we performed colour Doppler ultrasound of the testis in 12 azoospermic subjects affected by primary testicular pathology (four bilateral post-orchitis, four postradiotheraphy for cancer, four post-traumatic) aged 28.2+/-3.3 (mean+/-SD) years, in six subjects affected by obstructive azoospermia aged 29.7+/-2.4 years and in 20 age-matched fertile subjects (aged 28.6+/-2.5 years). The analysis of intratesticular vessels per organ was quantified using a semiquantitative score: category 0, no vessels visible; category 1, between one and three intratesticular vessels visible; and category 2, more than three vessels visible. In obstructive azoospermic patients and in fertile subjects there were always more than three intratesticular vessels. No intratesticular vessels were detected in eight testes (33.3%) and fewer than three vessels in 16 testes (66.6%) in subjects affected by primary testicular pathology. In azoospermic subjects the testicular structure of the testis was evaluated by diagnostic fine needle aspiration cytology (FNAC) performed in the middle portion of the testis. In non-obstructive azoospermic patients this procedure showed the presence of only Sertoli cells in all cases. When detectable vessels were present, a new aspiration was performed in these areas. In 12 out of 16 cases, spermatogenetic cells including mature spermatozoa, were found when the FNAC was performed in testicular regions showing the presence of blood vessels. These results indicate that colour Doppler sonography of the testis may be useful in the differential diagnosis of azoospermia and suggest the evaluation of the intratesticular blood vessel distribution before performing any method to retrieve intratesticular spermatozoa for intracytoplasmic sperm injection.
Ferlin A et al., 2020·Journal of clinical medicine·Free full text on PubMed Central
About one-fifth of couples has fertility problems in Western countries. Male factors are present in about half of them, either alone or in combination with female causes. Therefore, both partners should be evaluated simultaneously. The fertility status and/or specific conditions of each partner influence the clinical and treatment approach. This article summarizes in a practical way when, how, and why the male partner of an infertile couple should be investigated. The available evidence and international guidelines were used, interpreting, discussing, and expanding them from personal decades-long experience in this field. The aim is to delineate the most appropriate clinical approach for the male partner of infertile couples, considering traditional and emerging technologies and laboratory analyses in the context of their clinical significance. Components of the initial evaluation in men without known risk factors for infertility should include at minimum medical history, physical examination, and semen analysis. Semen microbiological examination, endocrine assessment, scrotal ultrasound, and transrectal ultrasound are suggested in most men and are mandatory when specific risk factors for male infertility are known to be present or when the initial screening demonstrated abnormalities. Full examination, including genetic tests, testicular histology, or additional tests on sperm, is clinically oriented and/or suggested after the results of initial investigations.
Grande G et al., 2022·Springer book chapter (Practical Clinical Andrology)·Free to read
Abstract Male infertility may depend by pre-testicular (for example, hypothalamic or pituitary diseases), testicular, and post-testicular (for example, obstructive pathologies of seminal ducts) causes. However, a large proportion (30–60%) of infertile males does not receive a clear diagnosis. In these cases, generally reported as idiopathic infertility, there is a strong suspicion of genetic factors yet to be discovered. Furthermore, male fertility may be influenced by a host of lifestyle risk factors such as environment, nutrition, exposure to infections, and smoking. Therefore, lifestyle and environment risk factors may have a role in many cases of idiopathic male infertility. In this chapter, we focus our attention on these risk factors, discussing three paradigmatic situations of interference between environment/lifestyle and male fertility, thus providing the pathophysiological basis of their detrimental impact on male fertility: exposure to environmental endocrine disruptors, such as perfluoro-alkyl substances (PFAS); exposure to viruses, such as HPV; effect of nutritional status and obesity.
The recent advances in assisted fertilization and gamete micromanipulation techniques have enabled fertilization in some forms of azoospermia; for example, epididymal sperm aspiration in obstructive azoospermia. Therefore knowledge of the specific degree of testicular damage is of primary importance, since other clinical parameters, such as FSH plasma levels and testicular volume, do not discriminate between the different testiculopathies. In order to further characterize the specific testicular conditions present in azoospermia, we have examined a large group of azoospermic subjects on the basis of testicular cytological analysis obtained by fine needle aspiration.
One hundred and twenty-two infertile, azoospermic men were studied by physical examination, FSH radioimmunoassay, testicular ultrasound examination and fine needle aspiration of the testes. Thirty-five infertile normozoospermic subjects were studied as controls.
The cytological analysis identified five different sub-types in azoospermic I, Sertoli cell-only syndrome; II, hypospermatogenesis; III, spermatogonial and/or spermatocytic arrest; IV, spermatidic arrest; and V, normal germ line. The testicular volume was reduced in groups I and II, while the FSH plasma levels were increased in groups I, II and III, suggesting a primary role of spermatids in the control of FSH secretion.
In azoospermic subjects, testicular cytological analysis permits the identification of different sub-types and this classification may be very important in determining therapy, particularly the choice between surgical treatment and the hypothetical use of assisted fertilization techniques by retrieval of epididymal or intratesticular spermatozoa or spermatids.
Male Fertility › Male Factor Causes › Azoospermia · Diagnostics › Ultrasound › Transvaginal Ultrasound
Andrea Canossa, A Di Nisio
A Canossa
PMID 34085393 34085393 DOI 10.1111/andr.13060 10.1111/andr.13060 Garolla et al. 2021, Garolla 2021
00240q980