Neither Rösti nor urban-rural divide Sperm quality in Swiss recruits remains stable
Good news for young Swiss men: contrary to the global trend, the sperm quality of Swiss recruits remains stable.
04.06.2026, 07:44
SDA
No time? blue News summarizes for you
- Compared to 2021, the sperm quality of Swiss recruits has hardly changed.
- In contrast to countries such as the USA or France, there is no urban-rural divide when it comes to sperm in this country.
- Why researchers believe the pandemic has affected sperm.
The quality of the sperm of Swiss recruits has not deteriorated: The study by the University of Zurich published in the June issue of the journal "New Microbes and New Infections" compares the data of 194 army recruits from 2021 with the data of 2523 young men examined between 2005 and 2017.
"The results showed that sperm quality parameters have not changed significantly in young Swiss men," the researchers wrote in the study. Important measured values such as semen volume, total sperm count, concentration, motility and morphology (shape) of the sperm remained relatively constant over the years.
In 2021, only 41% of recruits had at least one sperm parameter below the World Health Organization (WHO) guidelines. In the older study group (2005-2017), this proportion was still 62%.
Fitter soldiers in 2021
However, according to the researchers, this seemingly positive trend could also be explained by a bias in the selection of participants. The men in the 2021 study were active soldiers who had already successfully completed the recruitment process and therefore presumably had a higher level of basic physical fitness than the previous group.
The comparison group (2005-2017), on the other hand, also included men who had not yet undergone medical screening at enlistment. The researchers therefore concede that the current study is "possibly biased in favor of healthier and more physically fit men" in a direct comparison.
According to this study, place of residence and language do not appear to play a role in male fertility in Switzerland. There were no statistically relevant differences between urban and rural areas or between German-speaking Switzerland and French-speaking Switzerland and Ticino.
Unlike the USA or France
This is in contrast to international studies from the USA or France, which have repeatedly shown that men in rural regions exposed to intensive agriculture have poorer sperm values than urban population groups.
An analysis of Swiss recruit data from 2005 to 2017 published last year also showed regional differences and lower sperm values in areas with a high proportion of agriculture.
However, the Zurich research team admits that the small number of participants (194 men) in the current study is not sufficient to identify such subtle geographical "hotspots" or "coldspots" in a statistically reliable way.
Corona temporarily reduced the sperm count
A special focus of the study was on the effects of the coronavirus pandemic. The evaluations showed that the subgroup of recruits who tested positive for Sars-CoV-2 less than six months before the test had the lowest sperm concentration and the lowest total sperm count.
According to the study, this suggests "that COVID-19 may have had a transient effect on sperm quality". However, this negative effect did not prove to be permanent: in men whose Covid infection was more than 180 days ago, these losses were no longer detectable.
