Semen Examination Research Articles

Corrigendum to: Effects of mobile phone use on semen parameters: a cross-sectional study of 1634 men in China.

Mobile phones play an irreplaceable role in modern people's lives. However, the radiofrequency electromagnetic radiation produced by mobile phones has also caused increasing concern. A cross-sectional study was conducted to investigate the effect of radiofrequency electromagnetic radiation produced by mobile phones on semen parameters in 1634 men who underwent semen examination at the Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, China. Analysis of variance and multivariate linear regression were used to explore differences among different groups. A P P = 0.004 and P = 0.007), rapid progressively motile spermatozoa (P = 0.012 and P = 0.006) and total motile spermatozoa (P = 0.004 and P = 0.046). After adjustments for the confounding effects of age and body mass index by multiple linear regression, the results showed that the daily duration of mobile phone use had a negative effect on sperm motility. However, there was no statistically significant correlation between daily phone call duration and sperm motility. Therefore, the daily duration of mobile phone use may negatively affect sperm motility and impair male fertility.

Diagnostic tests in canine andrology - What do they really tell us about fertility?

Dog breeders often require breeding soundness evaluations which include andrological examinations of the genital organs, hormone measurements, and semen analyses. During the past decades, a considerable number of research results have been published, allowing diagnoses of specific andrological conditions and fertility assessment.For specific examinations, however, no standard procedures have been defined and for some parameters different reference ranges have been published. Therefore, examination results from different facilities are difficult to compare and profound conclusions regarding health and fertility of a male dog are not always possible.Conventional semen examination, however, is still useful in identifying deviations or no deviations from normality, especially if confounding factors are taken into account and if the exam is repeated in case of inconclusive findings. A standardization of examination procedures and reference ranges would help to harmonize the exchange of examination results and interpretation of the findings.

Sperm signatures of fertility and freezability

Apart from traditional semen examination parameters, there is not yet a set of functional markers for accurate determination of bull fertility and sperm freezability or cryopreservability, which are vital for production of food animals to feed the world. Therefore, reliable biomarkers are needed to objectively analyze semen quality and predict male fertility. Rapid developments in animal biotechnology have led to significant progress in developing science-based solutions for global problems in food animal production. Although andrology studies employing genomic and functional genomics (transcriptomics, proteomics, and metabolomics) approaches have elucidated some molecular aspects of sperm, there is also a need for additional mechanistic studies to ascertain the functional underpinnings. Biomarkers discovered through applying various -omics technologies using sperm from bulls with varying fertility phenotypes are valuable for semen evaluation and fertility prediction.

Exposure to ambient particulate matter affects semen quality: A case study in Wenzhou, China.

Particulate matter (PM), including PM2.5 (PM ≤ 2.5µm in aerodynamic diameter) and PM10 (PM ≤ 10µm in aerodynamic diameter), is a component of air pollutants, which is linked to semen quality. However, the available evidence of association needs to be strengthened, and some studies have conflicting results. To evaluate the potential impacts of PM on semen quality during the full (0-90 days before semen examination) and three key sperm development windows (0-9, 10-14, and 70-90 days before semen examination). We included 1494 infertile men in the main urban area in Wenzhou, China, who had undergone semen examinations for fertility between 2014 and 2019. The impacts were assessed by multivariable linear regression models. Overall, during the full sperm development window, PM2.5 and PM10 exposures were associated with declined progressive sperm motility (%) (β: -0.6; 95% confidence intervals (CIs): -1.07, -0.13 and -0.46; -0.59, -0.33) and total sperm motility (%) (-1.95; -2.67, -1.23 and -1.32; -1.82, -0.82), and associated with increased sperm concentration (106 /ml) (0.02; 0.006, 0.023 and 0.007; 0.001, 0.013) and total sperm number (106 ) (0.02; 0.01, 0.03 and 0.011; 0.004, 0.017). Furthermore, only PM2.5 exposure during the 10-14 days window was significantly associated with declined progressive motility (%) (-0.207; -0.395, -0.023). During the full sperm development window, PM exposure has an adverse impact on sperm motility and positive impacts on sperm concentration and total sperm number. The adverse impact was more severe in the 10-14 days window.

Effects of semen parameters and age on male sperm motility in Sichuan

Objective: Sperm motility describes the ability of sperm to move correctly in the female reproductive tract and reach the egg to fertilize it. It is mainly reflected by the proportion of forward motile sperm, which is one of the most important factors to judge male fertility. The sperm quality of men in Sichuan area was analyzed, and the influence of semen parameters and age on sperm motility and the effect of age on semen parameters were discussed. Method: According to the semen examination results of 18,200 male volunteers recruited from January 2018 to December 2021, the effects of age, semen volume, sperm concentration and sperm morphology on sperm motility were analyzed. effect on sperm quality. Divided into 5 age groups to analyze the effect of age on sperm quality. Result: The results manifested that semen volume, sperm concentration and normal morphology ratio showed a positive correlation with sperm motility, while there was a negative correlation between age and sperm motility, and sperm concentration had the greatest impact on sperm motility. With the increase of age, especially after the age of 40, the parameters of the semen decreased significantly. Conclusion: Semen parameters have an effect on sperm motility. The increase of age makes the sperm quality of elderly men decline, and the male reproductive time should not be too late.

Effects of semen parameters and age on male sperm motility in Sichuan

Objective: Sperm motility describes the ability of sperm to move correctly in the female reproductive tract and reach the egg to fertilize it. It is mainly reflected by the proportion of forward motile sperm, which is one of the most important factors to judge male fertility. The sperm quality of men in Sichuan area was analyzed, and the influence of semen parameters and age on sperm motility and the effect of age on semen parameters were discussed. Method: According to the semen examination results of 18,200 male volunteers recruited from January 2018 to December 2021, the effects of age, semen volume, sperm concentration and sperm morphology on sperm motility were analyzed. effect on sperm quality. Divided into 5 age groups to analyze the effect of age on sperm quality. Result: The results manifested that semen volume, sperm concentration and normal morphology ratio showed a positive correlation with sperm motility, while there was a negative correlation between age and sperm motility, and sperm concentration had the greatest impact on sperm motility. With the increase of age, especially after the age of 40, the parameters of the semen decreased significantly. Conclusion: Semen parameters have an effect on sperm motility. The increase of age makes the sperm quality of elderly men decline, and the male reproductive time should not be too late.

Standards in semen examination: publishing reproducible and reliable data based on high-quality methodology.

Biomedical science is rapidly developing in terms of more transparency, openness and reproducibility of scientific publications. This is even more important for all studies that are based on results from basic semen examination. Recently two concordant documents have been published: the 6th edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen, and the International Standard ISO 23162:2021. With these tools, we propose that authors should be instructed to follow these laboratory methods in order to publish studies in peer-reviewed journals, preferable by using a checklist as suggested in an Appendix to this article.

Extend the Survival of Human Sperm In Vitro in Non-Freezing Conditions: Damage Mechanisms, Preservation Technologies, and Clinical Applications.

Preservation of human spermatozoa in vitro at normothermia or hypothermia maintaining their functions and fertility for several days plays a significant role in reproductive biology and medicine. However, it is well known that human spermatozoa left in vitro deteriorate over time irreversibly as the consequence of various stresses such as the change of osmolarity, energy deficiency, and oxidative damage, leading to substantial limitations including the need for semen examinations, fertility preservation, and assisted reproductive technology. These problems may be addressed with the aid of non-freezing storage techniques. The main and most effective preservation strategies are the partial or total replacement of seminal plasma with culture medium, named as extenders, and temperature-induced metabolic restriction. Semen extenders consist of buffers, osmolytes, and antioxidants, etc. to protect spermatozoa against the above-mentioned adverse factors. Extended preservation of human spermatozoa in vitro has a negative effect on sperm parameters, whereas its effect on ART outcomes remains inconsistent. The storage duration, temperature, and pre-treatment of semen should be determined according to the aims of preservation. Advanced techniques such as nanotechnology and omics have been introduced and show great potential in the lifespan extension of human sperm. It is certain that more patients will benefit from it in the near future. This review provided an overview of the current knowledge and prospects of prolonged non-freezing storage of human sperm in vitro.

Investigation of the effect of COVID-19 infection on sperm DNA fragmentation

Aim. To compare sperm parameters and the DNA fragmentation in patients after the COVID-19 infection and in men without a history of infection.Materials and methods. Sperm parameters and DNA fragmentation index were evaluated in 172 patients examined in 2020–2022. Based on the data on COVID-19 infection in the anamnesis, the patient’s cohort was divided into three groups: group 1 (n = 16) and group 2 (n = 65) – patients who had an infectious disease less than 75 days and more than 75 days before the delivery of the ejaculate, respectively, and group 3 (control, n = 91) – men have no coronavirus infection. A standard semen examination was performed according by the WHO guidelines (2010) recommendation. Sperm DNA fragmentation was evaluated by fluorescent labeling of single- and double-strand DNA breaks (TUNEL method).Results. The percentage of spermatozoa with fragmented DNA in group 1 varies from 2 to 48 %, in group 2 – from 0.9 to 39 %, in group 3 (control group) – from 1.3 to 52.9 %. The average number of gametes with DNA breaks in group 1 (11.7 ± 3.3 %) is greater than in group 2 (10.6 ± 0.8 %) and in group 3 (10.7 ± 0.8%), but without a statistically significant differences. The proportions of patients whose DNA fragmentation index exceeds the reference value (≤15 %) in groups 1, 2 and 3 are 18.8; 13.8 and 18.7 %, respectively. The count of progressively motile (PR) and morphologically normal spermatozoa in group 2 is statistically significantly greater than in group 3 (22.5 ± 1.6 % vs 18.0 ± 1.2 % and 5.52 ± 0.47 % vs 4.03 ± 0.31 %, respectively).Conclusion. The content of sperm with fragmented DNA is higher in men examined less than 75 days after COVID-19 disease, than in patients, examined more than 75 days after COVID-19 and in men who have no history of this infection. In group 1 an increased DNA fragmentation index was noted mainly in patients who had suffered from the disease in a moderate form.

Do studies published in two leading reproduction journals between 2011 and 2020 demonstrate that they followed WHO5 recommendations for basic semen analysis?

STUDY QUESTIONDo publications that involve the interpretation of the results of a basic semen analysis, published in Human Reproduction and Fertility & Sterility between 2011 and 2020, give sufficient evidence in their methodology to demonstrate that they followed the technical methods recommended in the fifth edition of the World Health Organization (WHO) laboratory manual, entitled WHO Laboratory Manual for the Examination and Processing of Human Semen (WHO5)?SUMMARY ANSWEREvidence of methodological agreement of studies with the WHO5 recommendations was low, despite 70% of papers stating that they followed WHO5 recommendations.WHAT IS KNOWN ALREADYA basic semen analysis is currently an integral part of infertility investigations of the male, but method standardization in laboratories remains an issue. The different editions of the WHO manual for the basic semen analysis (WHO1–6) have attempted to address this by providing increasingly rigorous methodological protocols to reduce experimental error. However, to what extent these methods are followed by studies that involve the interpretation of the results of basic semen analysis remains unknown.STUDY DESIGN, SIZE, DURATIONA survey of the technical methods used to perform a basic semen analysis was conducted on studies published in two leading reproduction journals (Human Reproduction and Fertility & Sterility) between 2011 and 2020.PARTICIPANTS/MATERIALS, SETTING, METHODSThe literature search was performed on the electronic databases PUBMED and MEDLINE Ovid between January 2021 and March 2021. The MeSH terms included in the search were ‘sperm concentration’ OR ‘sperm motility’ OR ‘sperm morphology’ OR ‘sperm vitality’ OR ‘male fertility’ AND ‘human spermatozoa’ NOT ‘animals’. A total of 122 studies were available for analysis.MAIN RESULTS AND THE ROLE OF CHANCEIn total, 70% of the studies cited WHO5 in their methods section. Of the remaining studies, 10% cited the fourth edition of the WHO laboratory manual (WHO4), 7% cited both WHO4 and WHO5, 1% cited the third edition of the WHO laboratory manual (WHO3), and 12% did not cite the WHO at all. Overall methodological agreement with WHO5 recommendations was poor, with the main reason for this lack of agreement being that the research studies did not disclose specific details of the technical methods and equipment used.LIMITATIONS, REASONS FOR CAUTIONIn the case of studies that did not disclose any specific technical methods that they used, we did not attempt to contact these authors and so were unable to confirm the agreement between their technical methods and WHO5 recommendations.WIDER IMPLICATIONS OF THE FINDINGSOur findings suggest there is an urgent need to develop strategies to address standardization in reporting the results of a semen analysis for publication. This is particularly timely given the recent publication of WHO6 and ISO standard 23162 for the basic examination of human semen.STUDY FUNDING/COMPETING INTEREST(S)There was no funding for this project. C.L.R.B., as an employee of the University of Dundee, serves on the Scientific Advisory board of ExSeed Health (from October 2021, financial compensation to the University of Dundee) and is a scientific consultant for Exscientia (from September 2021, financial compensation to the University of Dundee). C.L.R.B. has previously received a fee from Cooper Surgical for lectures on scientific research methods outside the submitted work (2020) and Ferring for a lecture on male reproductive health (2021). C.L.R.B. is Editor for RBMO.TRIAL REGISTRATION NUMBERN/A.

Evaluation of Different Methods Used in Morphological Examination of Canary Sperm

By determining the species-specific structure by morphological examination of the sperm, it is possible to improve some of the disadvantages related to short and long-term storage and use in artificial insemination applications. When the morphology of the canary spermatozoon is evaluated, it is seen that it has a long indented acrosome as well as a rather long flagellum. To determine the morphological structure of canary semen, morphological examination methods used in different poultry can be applied and visually evaluated with different shapes. This study aims to provide information about the comparison and usability of various staining methods used in the morphological examination of canary semen from songbirds. In this study, semen from 12 male Gloster canaries was collected to determine morphological parameters in semen. Collected semen with different morphological evaluation methods; Fixation with 5% formaldehyde, Formalin fixation and Giemsa staining, Giemsa staining, Formalin fixation, and SpermBlue staining and SpermBlue staining were evaluated. In the results of the study, while the nucleus was more prominent in Giemsa staining compared to other staining methods used for morphological evaluation, acrosome was observed in SpermBlue and Giemsa staining. On the other hand, when the sperm fixed with 5% formaldehyde solution were evaluated, it was seen that the acrosome and nucleus were indistinguishable, while the changes in the flagellum were determined much more clearly. As a result of the study, it was reported that the morphological structure of canary semen could be evaluated with all morphological examination methods used.

The statistical foundation of the reference population for semen analysis included in the sixth edition of the WHO manual: a critical reappraisal of the evidence.

In the most recent version of the ‘WHO Laboratory Manual For The Examination And Processing Of Human Semen’, the updated target population used to infer reference values included 3589 fertile subjects, representative of 12 countries and 5 continents, and 10 studies. We have critically evaluated the newly proposed distribution of semen examination results using an approach borrowed from clinical chemistry laboratories and based on the recommendations of the International Federation of Clinical Chemistry for estimation of reference intervals. Surprisingly, most prerequisites to produce common reference intervals through multicentric data were not met. Moreover, when we assessed with the bootstrap method the descriptive reference values obtained from raw data of the 10 individual studies for sperm concentration, sperm number, motility and normal forms, we found that none of the populations was completely correctly described by the reference centiles. We concluded that aggregated data used to build the reference distribution cannot be considered to originate from the same population, and this can result from real differences among individuals or different methodological approaches used in the various studies. Transferability conditions across studies did not seem to have been met. Our findings strengthen the relevance of concerns regarding the use of reference populations in the World Health Organization manual to discriminate between fertile and infertile men.

Comment on Boitrelle et al. The Sixth Edition of the WHO Manual for Human Semen Analysis: A Critical Review and SWOT Analysis. Life 2021, 11, 1368.

We wish to congratulate Boitrelle and colleagues for their comprehensive critical review on the Sixth Edition of the WHO Laboratory Manual for Human semen examination [...].

P-085 Use of an artificial intelligence tool to assess single-sperm motility variables related to bias preference of ICSI sperm selection practice, normal fertilization, and blastocyst formation

Abstract Study question Which single-sperm WHO motility variables are associated with ICSI sperm selection preference, normal fertilization, and blastocyst formation when assessed by an artificial intelligence platform? Summary answer Injected sperm had higher VSL, VAP, and LIN compared with non-injected. Higher STR was associated with fertilization and higher WOB and less HMP with blastulation. What is known already Sperm selection for intracytoplasmic sperm injection (ICSI) is key to its success. Currently, the procedure may be subjective although the embryologist selects rapidly from a small population of sperm. There is no consensus on specific motility variables for single-sperm selection. SiD (IVF 2.0 Limited, UK) software is able to assess all sperm in a visual field and accurately compute the motility variables for each sperm in real-time. SiDTM could help to understand the association between motility variables related to ICSI success and to assess the differences in sperm selection practice between different clinics and operators. Study design, size, duration 473 ICSI videos and their corresponding outcome were retrospectively analyzed using SiD software and assessed against normal fertilization (2PN), and blastocyst formation (BF), from four fertility clinics in different countries between July 2021 to December 2021. Ethical approval was obtained. This study was non-interventional. The study parameters were defined as sperm that were selected or non-selected, 2PN, and BF. Participants/materials, setting, methods Motility variables were computed from ICSI videos for VSL, VCL, LIN, VAP, ALH, WOB, STR as defined by the WHO manual for the examination and processing of human semen; and HMP, a metric associated with sperm-head movements. Injected sperm were manually identified and the injection was visually verified by a senior embryologist. Extracted motility variables were standardized according to each clinic and PVP concentration. Study groups were tested with a two-sided Mann-Whitney U test. Main results and the role of chance Video analysis identified 304 selected and 9543 non-selected sperm. 2PN and BF status was known for 302 and 301 injected oocytes respectively (2PN rate: 79%, BF rate: 53%). Embryologists used VSL, VAP, and LIN as the preferred motility criteria to select sperm (p < 0.001). Using data from all clinics, we found a tendency for STR (p = 0.12) and LIN (p = 0.14) for 2PN and WOB (p = 0.11) and VAP (p = 0.18) for BF. There was partial consistency on sperm selection criteria amongst clinics: Clinic1 selected VSL, VAP, and LIN as the main variables to select sperm; Clinic2 VSL, WOB, and LIN; Clinic3 VSL, VAP, and VCL; and Clinic4 ALH, VCL, and VAP (p < 0.001). For Clinic1 higher HMP showed a correlation (p = 0.06, n = 21) to 2PN, while higher WOB (p = 0.12, n = 21) did for BF. Clinic2 showed a limited association to higher STR and 2PN (p = 0.12, n = 120), and a significant association between higher WOB and BF (p < 0.05, n = 120). Clinic3’s data suggested that higher STR was associated with 2PN (p < 0.05, n = 97) and low HMP with BF (p < 0.05, n = 97). Limitations, reasons for caution This retrospective study needs to be repeated prospectively with larger numbers in more locations using embryologists with different levels of ICSI experience. Clinical outcome data such as clinical pregnancy, miscarriage, and live birth impact is still required. Wider implications of the findings SiD was able to track and extract motility features from single sperm. SiDTM could assist embryologists in real-time to select sperm during ICSI and could be used as a training tool to reduce variability among embryologists. Trial registration number RPA-2021-03

O-052 Male fertility testing - new horizons, ideas and research

Abstract The diagnosis of male infertility is primarily based on the macroscopic analysis of semen and microscopic analysis of sperm (mainly concentration and count, motility, and morphology) through the seminogram. Although six different editions of the “WHO Manual for the Laboratory Examination and Processing of Human Semen” have been published to date, the diagnostic potential of this approach has been called into question. Additionally, recent studies report a significant decline in sperm counts and fecundability in general. Therefore, the need for alternative diagnostic approaches that effectively predict fertility in men is urgently needed. In this talk we will cover what the limitations of the current semen analysis are, what novel tests are available and more important the new horizons, ideas and research in male fertility testing. We will focus in: 1) the usefulness of sperm functionality analyses (e.g., vitality, plasma membrane and acrosome integrity, plasma membrane lipid disorder, mitochondrial membrane potential, mitochondrial peroxide and superoxide levels, intracellular levels of ROS and Ca2+, and sperm chromatin condensation, among others), 2) the clinical implications of sperm DNA fragmentation and the newest recommendations for assisted reproduction clinics, 3) the newly described monogenic causes of human male infertility, and 4) how comorbidities are related with infertility.

Advantages of semen analysis by quantitative kariological analysis of immature germ cells in azoospermic and cryptozoospermic patients

Introduction. Obtaining spermatozoa in azoospermic men is a relevant objective. Quantitative karyological analysis of immature germ cells (QKA IGCs) allows to characterize the progression of spermatogenesis through different meiotic stages, that present some advantages in comparison with standard semen analysis (SSA) examination and testicular biopsy.The study objective was to analyze SSA and QKA IGCs for detecting of germ cells in the ejaculate of patients with suspected azoospermia.Materials and methods. The ejaculate samples of 20 men with suspected azoospermia of various etiology (genetically determined and idiopathic male infertility) were studied. The ejaculate samples were processed in parallel by two methods, SSA performed according to the WHO laboratory manual for the examination and processing of human semen (2010) and QKA IGCs.Results. Using by the SSA, cryptozoospermia was detected in 1 (5 %) of 20 ejaculate samples. QKA IGCs revealed cryptozoospermia in 10 (50 %) samples, including 53 % of patients (with azoospermia according to SSA). The number of spermatozoa in the ejaculate sediment as a result of QKA IGСs (2.25 ± 4.22) is higher (p = 0.019; U = 113) than the number of spermatozoa as a result of the SSA – 0.25 ± 1.12.Conclusion. In patients with suspected azoospermia, the effectiveness of detecting cryptozoospermia using the QKA IGCs method is significantly (10 times) higher than the SSA. This method complements SSA and makes it possible to detect non-invasively the meiosis defects, including cases with an extremely low concentration of spermatozoa. The analysis is safe for the patient and can be performed repeatedly to track the dynamics of semen parameters.

Effects of Oocyte Cytoplasmic Central Granulation on Embryonic Development, Blastocyst Formation, and Pregnancy Outcome in Assisted Reproductive Technology and Its Mechanism.

To investigate whether oocyte centrally located cytoplasmic granulation (CLCG) affects embryonic development, blastocyst formation, and pregnancy outcomes in assisted reproductive technology, fifty patients with CLCG in all oocytes were selected as the CLCG group. Then, 150 patients with no abnormal oocyte morphology were randomly recruited as the control group. Both groups underwent laparoscopy, hysterosalpingography (HSG), vaginal ultrasound, and male semen examination. The down-regulation regimen was selected regarding the patient's ovarian reserve. The egg maturation rate, normal fertilization rate, cleavage rate, available embryo rate, and high-quality embryo rate in the CLCG group were greatly inferior to those in the control group, with remarkable differences (P< 0.05). CLCG grading of oocytes after 30 cycles in the CLCG group indicated that there were 36 cases in the mild group and 14 cases in the severe group. The egg maturation rate in the mild group was lower than that in the severe group, with a notable difference (P< 0.05). The fertilization rate, cleavage rate, available embryo rate, and high-quality embryo rate in the mild group were higher than those in the severe group, with a notable difference (P< 0.05). Compared with the control group, there was no considerable difference in the implantation rate, clinical pregnancy rate, and abortion rate between the CLCG group (P> 0.05). In summary, oocyte CLCG may affect fertilization, embryonic development, and blastocyst formation, but not pregnancy outcomes.

Associations between Meat and Vegetable Intake, Cooking Methods, and Asthenozoospermia: A Hospital-Based Case-Control Study in China.

Background: The role of meat and vegetable intake in the development of asthenozoospermia has been controversial, and the role of cooking methods for meat and vegetables in the association has yet to be determined. The present study aimed to illuminate the relationship between the consumption and cooking methods of meat and vegetables and the risk of asthenozoospermia. Methods: In this hospital-based case–control study, we enrolled 552 patients with asthenozoospermia and 585 healthy controls. Dietary information was assessed using a validated self-administered food frequency questionnaire. Asthenozoospermia was diagnosed according to the fifth edition of the WHO laboratory manual for the examination and processing of human semen. Results: Participants in the highest tertile of total meat and unprocessed meat intake had a 44% and 39% lower risk of asthenozoospermia than those in the lowest tertile (OR = 0.56, 95% CI: 0.37, 0.87 and OR = 0.61, 95% CI: 0.40, 0.93), respectively. Participants with the highest processed meat consumption showed higher risk (OR = 1.44, 95% CI: 1.01, 2.06). Raw vegetable consumption was negatively associated with the risk of asthenozoospermia (OR = 0.67, 95% CI: 0.45, 0.98). The stir-frying cooking method for meat was associated with increased risk of asthenozoospermia (OR = 1.58, 95% CI: 1.02, 2.46). Conclusions: Intake of total meat, unprocessed meat, and raw vegetable may reduce asthenozoospermia risk, while higher consumption of processed meat may increase the risk. Cooking methods may play a role in these associations. These findings need to be confirmed in large and prospective cohort studies.

Relationship between spermatogenesis, DNA fragmentation index, and teratozoospermia index

Infertility has proven a global medical issue, with 15-20 percent of married worldwide experiencing difficulties in conceiving. One of the causes of male infertility is sperm morphology abnormalities, or teratozoospermia, which is often associated with sperm DNA damage. Teratozoospermia can increase sperm DNA fragmentation through several mechanisms, including abortive apoptosis and induce ROS formation. Unfortunately, many forms of sperm flaws, including genetic defects, could not be validated by routine semen examination. In the Sixth Edition, WHO introduced a more thorough sperm morphology examination, named the teratozoospermia index (TZI), in which every aberrant sperm is examined for up to four defects. Analyzing spermatozoa abnormalities in more detail can provide an overview of the function of the male reproductive organs, particularly the testes and epididymis. However, using this method is not entirely easy due to subnormal variations between cells so that quality control may be needed when using TZI for sperm morphology evaluation.

Chronic Immune-Mediated Orchitis Is the Major Cause of Acquired Non-obstructive Azoospermia in Dogs

Azoospermia, the lack of spermatozoa in the ejaculate, is the most common finding in infertile but otherwise healthy male dogs and represents an increasing reproductive health issue in men, too. The diagnosis can be further classified as non-obstructive azoospermia and obstructive azoospermia due to an obstruction of the deferent ducts. Although non-obstructive azoospermia comprises more than half of azoospermic cases in men and is a common cause of infertility in the male dog, knowledge of the underlying etiology and pathophysiology is still strongly limited, and much uncertainty exists about the true incidence and possible treatment options. Therefore, this study aims to investigate and characterize infertile canine patients in detail by combining results of andrological examinations (clinical parameters, semen analysis, bacterial examination of semen, and Brucella canis serology), endocrine analysis (luteinizing hormone, testosterone, estradiol-17ß, and thyroid function), analysis of the alkaline phosphatase in seminal plasma, and histological assessment of testicular biopsies of 10 azoospermic dogs. Our results not only verify non-obstructive etiology for 9/10 cases of canine azoospermia but also further identified significant histopathological changes of the testicular tissue with severely disrupted spermatogenesis, including fibrotic remodeling, vacuolization, Sertoli-cell-only syndrome, tubular shadows, and an increase of the interstitial and vascular area. In addition, three dogs showed local and six dogs generalized immune-cell infiltration, indicating chronic immune-mediated orchitis. Only in one case (no. 1) that no immune cells were found, and obstructive azoospermia was suspected due to low alkaline phosphatase activity. Furthermore, the detection of anti-thyroideal antibodies in two dogs indicates an autoimmune thyroid disease and a correlation between the occurrence of thyroidal disorders and azoospermia. Our results confirm previous findings and contribute additional evidence suggesting that chronic immune-mediated orchitis is the major cause of infertility in dogs. Further studies should focus on uncovering underlying inflammatory processes behind spermatogenic failure in these cases and identify possible treatment options to (re-)initialize spermatogenesis.