When men stayed at home during the pandemic it seems their sperm became less active too.
Researchers came to the finding while investigating a widely held view that sperm counts in men are dropping around the world.
While they did not find any drop in numbers, they did discover the sperm collected during lockdown was swimming a lot less.
Scientists studied semen from 6,758 men aged between 18-45 collected by the biggest sperm bank in the world, Cryos International in Denmark.
The research in the journal Human Reproduction found that samples of sperm concentration, taken from men applying to be sperm donors between 2017 and 2022, ‘did not change significantly over a six-year period’.
Researchers studied semen from 6,758 men aged between 18-45 collected by the biggest sperm bank in the world, Cryos International in Denmark. The research in the journal Human Reproduction found that the samples, taken from men applying to be sperm donors between 2017 and 2022, found that sperm concentration ‘did not change significantly over a six-year period’
Research has previously suggested that sperm counts in men are falling. Pictured, one 2022 global study in the journal, Human Reproduction Update. Graph shows: The rate sperm concentration is falling globally from samples collected from 1972 to 2000 (orange) and since 2000 (red)
But they did find that there was a big difference in motility — the ability of sperm to swim spontaneously.
Co-author Professor Allan Pacey from The University of Manchester said: ‘It is commonly believed by that sperm counts in men are falling.’
He said a recent ‘metastudy’ — which collated data from 44 pieces of research — by Dr Hagai Levine of the Hebrew University of Jerusalem found sperm counts had fallen by as much as 2.64 per cent per year in men worldwide since 2000.
Professor Pacey, however, said: ‘We did not see such a change and that suggests that in this population of sperm donor applicants, in these four Danish cities, sperm concentrations have not changed between 2017 and 2022.’
But the total numbers of swimming sperm provided for testing had declined by 16 per cent and 22 per cent respectively from 2019 to 2022.
Co-author Professor Robert Montgomerie from Queen’s University, Canada said: ‘The decline in measures of sperm motility between 2019 and 2022 was an unexpected finding.
‘This decline roughly corresponds to the onset of the worldwide Covid pandemic.
‘While there is no evidence to suggest that the SARS-CoV-2 virus is directly affecting sperm, we speculate whether the widespread lockdowns may have led to changes in working pattens, diet, and levels of physical activity which we already know can impact sperm motility.’
The study authors were not able to collect information on the health or lifestyles of the men applying to be sperm donors that could help to identify factors that may account for the decline in sperm motility.
The current study only looked at samples collected in 2017 as from this date more accurate computational methods were used to count sperm — before this counting was carried out manually.
