Many scientists believe that spermatozoan counts across the world are on ageneral decline , with potentially serious ramifications for fertility and manful health – but what if they ’re improper ? A Modern subject field from researcher in the UK , Canada , and Denmark evoke the true situation may not be so straightforward , and that spermatozoon quality , rather than measure , should be the focus .

information suggesting that sperm count are dropping has attracted a lot of attention in recent years , with some going to far as to call it a looming “ spermageddon ” . Over the last 30 - plus years , a strand of study have raised the alarm about worsen spermatozoon quantity inindustrialized country , with vulnerability toeveryday chemicals , cannabis economic consumption , and recentlymicroplasticscoming under fire as possible suit .

But now , a new subject area has come in to a rather dissimilar stopping point .

The squad analyzed data from 6,758 men mature 18 - 45 from four cities in Denmark who had applied to become spermatozoan donors at the creation ’s largest sperm bank , Cryos International . The data cover the period between 2017 and 2022 , and all samples were assessed in the same way .

“ It is usually believed [ that ] sperm counts in men are falling , ” said co - source Professor Allan Pacey of the University of Manchester , in a statement email to IFLScience .

“ We did not see such a change and that evoke that in this population of sperm donor applicant , in these four Danish metropolis , sperm concentrations have not changed between 2017 and 2022 . ”

dig deeper into their findings , the squad did observe a belittled decrease in spermatozoon concentration and total sperm counting between 2019 and 2022 of around 0.1 - 5 percent year - on - year . This modification , however , was not statistically pregnant .

There was one outcome that surprised the team . “ The declivity in standard of sperm motility between 2019 and 2022 was an unexpected finding , ” commented conscientious objector - author Professor Robert Montgomerie .

Motile sperm concentration and total motile sperm count – both measures of spermqualityrather than absolute amount – decreased by 16 and 22 pct , severally , from 2019 - 2022 .

“ This decline roughly corresponds to the onset of the worldwideCOVID-19pandemic , ” Montgomerie noted . “ While there is no grounds to intimate that the SARS - CoV-2 virus is directlyaffecting spermatozoon , we job whether the far-flung lockdown may have led to changes in work patterns , dieting , and levels of physical natural action which we already hump can impact sperm motion . ”

It ’s an intriguing mesmerism , but one the authors stress in their newspaper can not be like a shot dictated from their information .

It ’s also not readable how well this universe of volunteer sperm donor can be generalized to men across Denmark as a whole , noted carbon monoxide - source Anne - Bine Skytte , Medical Director of Cryos International .

Any fresh inquiry that calls into motion a well - build melodic theme is adhere to comeunder scrutiny . But Professor of Reproductive Medicine Dr Chris Barratt , who is based at the University of Dundee and was not straight off involved in the study , praise the writer ’ glide slope in a input to theScience Media Centre :

“ study to date have badly investigated spermatozoon movement but this study has done a good job . This data is important as it evince , on a large sample position with high quality method acting , that we should be focussed on spermatozoan caliber , rather than spermatozoan quantity . ”

The selflessness of those who are willing to donate their sperm to help hoi polloi experiencing natality issues can also help advance scientific discovery – as Skytte put it , “ This is an unexpected benefit of their generosity . ”

The authors evoke that collecting more modus vivendi data point from bestower could help oneself us pinpoint the possible causes behind refuse spermatozoon quality at a universe level , which could then also be used to develop personalized interventions for bestower like to better their own sperm quality , make it a win - winnings .

In short , this sketch would propose that the old adage of “ tone , not quantity ” is blast on the money .

The bailiwick is publish in the journalHuman Reproduction .