Introduction: Infertility affects one in every six couples in developed countries, and approximately 50% is of male origin. In 2021, sperm DNA fragmentation (SDF) testing became an evidence-based test for fertility evaluations depicting fertility more clearly than standard semen parameters. Therefore, we aimed to summarize the potential prognostic factors of a higher SDF. Methods: We conducted a systematic search in three medical databases and included studies investigating any risk factors for SDF values. We calculated mean differences (MD) in SDF with 95% confidence interval (CI) for exposed and non-exposed individuals. Results: We included 190 studies in our analysis. In the group of associated health conditions, varicocele (MD = 13.62%, CI: 9.39–17.84) and impaired glucose tolerance (MD = 13.75%, CI: 6.99–20.51) had the most significant increase in SDF. Among malignancies, testicular tumors had the highest impact, with a maximum of MD = 11.3% (CI: 7.84–14.76). Among infections, the overall effects of both Chlamydia and HPV were negligible. Of lifestyle factors, smoking had the most disruptive effect on SDF – an increase of 9.19% (CI: 4.33–14.06). Different periods of sexual abstinence did not show significant variations in SDF values. Age seemed to have a more drastic effect on SDF from age 50 onwards, with a mean difference of 12.58% (CI: 7.31–17.86). Pollution also had a detrimental effect – 9.68% (CI: 6.85–12.52). Conclusion: Of the above risk factors, varicocele, impaired glucose tolerance, testicular tumors, smoking, pollution, and paternal age of over 50 were associated with the highest SDF. Trial registration: CRD42021282533.

Chronic genital tract inflammations are a frequent cause or at least a concomitant factor of male fertility disturbances. The diagnosis is difficult because of the mostly asymptomatic course of the disease. Therefore, determination of biochemical markers of inflammation in addition to the number of leucocytes in the seminal plasma has been recommended. The aim of the study was to find out whether determination of granulocyte elastase and interleukin-6 provide comparable and reliable results with regard to diagnosis of genital tract inflammation; in addition, the association between genital tract inflammation and semen quality should be evaluated with special focus on potentially disturbed sperm functions like sperm motility and DNA integrity. In a prospective study, the concentrations of interleukin-6 (IL-6) and granulocyte elastase were determined in seminal plasma samples from 340 patients to investigate the relationship with other parameters of genital tract inflammation such as the number of peroxidase-positive cells and conventional semen parameters. Microbiological investigations were included. As post-testicular inflammatory influences may cause sperm DNA damage, the correlation between IL-6 and elastase and DNA integrity was evaluated by the sperm chromatin structure assay. IL-6 and elastase were significantly correlated both with each other (P < 0.01) and the number of peroxidase-positive cells (P < 0.01). IL-6 showed a highly significant negative correlation with sperm vitality (P < 0.01) and a significant negative correlation with sperm motility (P < 0.05). Elastase concentrations were highly significantly associated with the number of peroxidase-positive cells (P < 0.01) and negatively correlated with sperm vitality (P < 0.01). Moreover, there were significantly negative correlations with sperm motility (P < 0.05), progressive motility according to WHO a quality (P < 0.05) as well as sperm morphology (P < 0.05). In addition, a significant negative correlation was observed between elastase concentrations and percentage of spermatozoa with intact DNA, which may suggest the use of anti-inflammatory treatment. It can be concluded that both IL-6 and granulocyte elastase are useful and suitable as markers for silent genital tract inflammation; in contrast to previous contributions there were clear correlations of IL-6 and granulocyte elastase with sperm parameters, the relationship of elastase with semen quality being more marked. Moreover, the results of the study confirm the need for a change of the threshold value of peroxidase-positive cells according to WHO definition to lower levels for definition of silent genital tract inflammation.

Agarwal A, et al. World J Mens Health. 2021 Apr;39:e17. https://doi.org/10.5534/wjmh.210025

Background: Little is known about the potential role of central obesity among men. Our first aim was to confirm what is already known from prior research, namely that both BMI and WHR are inversely associated with selected semen parameters. Our second aim was to examine the potential role of central obesity by assessing if there was a difference between BMI and WHR regarding their relationships to these selected semen parameters. Methods: In this cross-sectional study between January 2011 to January 2018, we analyzed semen samples from 1169 patients who visited an andrology clinic in Budapest for infertility reasons. Variables assessed were: body measurements (height, weight, waist circumference, and hip circumference), and the results of semen analysis (sperm concentration, total sperm count, progressive sperm motility, and normal sperm morphology). Results: The mean height and weight were 180.6 cm and 87.3 kg, respectively – the mean BMI was 26.8. The mean waist and hip circumferences were 100.9 cm and 94.8 cm, respectively – the mean waist to hip ratio was 0.94. The mean sperm concentration, total sperm count, and percents of progressive motility and normal morphology were 48.7 M/ml, 165 million, 21.2, and 4.8%, respectively. Both BMI and WHR were significant correlates in all semen parameter regression models. When comparing the parameter estimates for BMI with those for WHR for each semen parameter, the parameter estimate for WHR was significantly lower (indicating a stronger negative association) than that for BMI for progressive motility and total sperm count, but not for normal morphology or concentration. Conclusions: Our study is the first to examine, using a large patient sample, the potential role of central obesity by comparing the difference between BMI and WHR as they relate to selected semen parameters. Our findings indicate a potential role of central obesity for progressive motility and total sperm count, but not for normal morphology and concentration. Despite the limitations and the exploratory nature of this study, we can conclude that our results point to a potential role of central obesity in male infertility, but this finding should be confirmed and further explored in future research. Trial registration: The trial was retrospectively authorized after the data collection on September 24, 2018. Registration number: SE RKEB: 169/2018.