ReviewNature reviews. Urology2022
Spatiotemporal trends in human semen quality.
Review in Nature reviews. Urology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 34 papers, 2 of them syntheses that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
34 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Association between body mass index and semen quality: a systematic review and meta-analysis.International journal of obesity (2005) · 2024Pooled it
- Global trends in semen quality of young men: a systematic review and regression analysis.Journal of assisted reproduction and genetics · 2023Pooled it
- A decade of semen quality trends in Libya: nonlinear temporal patterns, age effects, and WHO 2010-2021 reclassification.Reproduction & fertility · 2026Article
- Integrating Sperm Microscopy, Environmental Exposures, and Lifestyle Factors for Male Fertility Analysis: Protocol for the Nippon Semen and Environmental Exposure Database (N-SEED) Cross-Sectional Study.JMIR research protocols · 2026Article
- Epigenetic sperm quality testing for predicting fertility treatment success: a real-world and multi-site analysis.Journal of assisted reproduction and genetics · 2026Article
- Physiological interplay among obesity, male fertility, and aryl hydrocarbon receptor in human and mice: A mini review.Open veterinary journal · 2026Review
- Declining semen quality in North Africa: from 2019 to 2024: retrospective multicentric study of 21,585 patients.Reproduction & fertility · 2026Article
- Environmental determinants of male infertility: emerging threats and technological interventions.Frontiers in medicine · 2026Review
- Exploring geographical differences in semen quality of young men using spatial dependence analysis.Human reproduction (Oxford, England) · 2025Article
- Decrease or increase in sperm concentration? The data among fertile Chinese males in 40 years.Journal of assisted reproduction and genetics · 2025Article
- Perceived stress in relation to testicular function markers among men attending a fertility center.Fertility and sterility · 2025Observational
- Urology on a changing planet: links between climate change and urological disease.Nature reviews. Urology · 2025Review
- A comparative study of the effects of the COVID-19 pandemic on semen quality based on a nationwide relaxation of COVID-19 restrictions in China at the end of 2022.Translational andrology and urology · 2025Article
- Correlation of IGF2 levels with sperm quality, inflammation, and DNA damage in infertile patients.Asian journal of andrology · 2025Article
- Impact of Endocrine Disruptors on the Genitourinary Tract.Journal of xenobiotics · 2024Review
- The moderation effect of GSTM1/GSTT1 gene polymorphisms on the association of sperm mitochondrial DNA copy number and sperm mobility.Scientific reports · 2024Article
- Microplastic presence in dog and human testis and its potential association with sperm count and weights of testis and epididymis.Toxicological sciences : an official journal of the Society of Toxicology · 2024Article
- Recent decline in sperm motility among donor candidates at a sperm bank in Denmark.Human reproduction (Oxford, England) · 2024Article
- Article
- Association between Sperm Mitochondrial DNA Copy Number and Concentrations of Urinary Cadmium and Selenium.Biological trace element research · 2024Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Over the past four decades, studies of various designs have reported spatial and temporal trends in human semen quality. Several standardized-methodology studies in homogeneous populations that compare specific cities within a country or a continent provide clear evidence of geographical differences in sperm production, even over short distances within the same country. Human sperm production is widely believed to be declining over time, but evidence from the scientific literature is less clear. Studies based on repeated cross-sectional data from a single centre have shown mixed results. Among the numerous retrospective studies conducted in a single centre, only some included homogeneous groups of men and appropriate methods, and most of them suggest a temporal decrease in human sperm production in the geographical areas considered. Conclusions reporting temporal trends in sperm production that came from existing retrospective multicentre studies based on individual semen data and those using means, medians or estimates of sperm production are questionable, owing to intrinsic limitations in the studies performed. Regardless of study design, studies on the percentage of motile or morphologically normal spermatozoa are still limited by the inherent variability in assessment. Overall, available data do not enable us to conclude that human semen quality is deteriorating worldwide or in the Western world, but that a trend is observed in some specific areas. To understand these trends and contrasts in sperm and semen quality, prospective studies should be encouraged and combined with assessment of the male exposome.
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