A new research paper warns that COVID-19 can affect men's sperm, but it may not be that simple.
Researchers from the Justus-Liebig University in Giessen, Germany published a study in Reproduction, showing that the sperm of men who had been diagnosed with COVID-19 showed increased sperm cell death, inflammation and oxidative stress compared to the sperm of men who had not had the virus.
'These effects on sperm cells are associated with lower sperm quality and reduced fertility potential' said lead researcher Behzad Hajizadeh Maleki. 'Although these effects tended to improve over time, they remained significantly and abnormally higher in the COVID-19 patients, and the magnitude of these changes were also related to disease severity.'
The research looked at sperm samples from 84 men who previously had COVID-19 and 105 who had not. Samples were collected every ten days for 60 days, and were screened for a number of indicators of sperm quality. On average, the samples from men who had been ill with COVID-19 had reduced sperm concentration and mobility, and had four times more misshapen sperm.
It is known that the cells in the testes have the ACE2 receptor, which the SARS-CoV-2 virus uses to infect cells. This issue was discussed in December at the annual conference of the Progress Educational Trust (PET) – the charity that publishes BioNews (see BioNews 1077). However, it is unknown if this is related to the effect on sperm.
'Being ill from any virus such as flu can temporarily drop your sperm count (sometimes to zero) for a few weeks or months. This makes it difficult to work out how much of the reductions observed in this study were specific to COVID-19 rather than just from being ill' said Dr Channa Jayasena, a reproductive endocrinology and andrology specialist from Imperial College London, who was not involved in the study.
Professor Allan Pacey who spoke at the PET conference pointed out that 'sperm production takes just under three months (roughly) to be completed from start to finish... It would have been more useful to see whether there was a difference at 90 days between the two groups.'
He also added that the men with COVID-19 had been hospitalised and would have been given a number of medications, which the control group were not.