With spermatozoa that are less motile, less concentrated, and with altered shapes, the sperm of men who have had a severe form of Covid-19 are of poorer quality, according to the results of a German study involving a small number of patients. Is the male reproductive system in the spotlight and being added to the list of sequelae of the disease? Further work is needed to find a link between fertility and Covid-19.
Covid-19 can alter sperm quality in men who have it. This is according to a German study published in the journal Reproduction, which involved only a small number of patients and whose results need to be confirmed by further work. The team of researchers from the Justus Liebig University of Giessen regularly examined the semen of 84 men (under 40 years old) infected with the coronavirus, most of them with a severe form, for two months and compared it with that of 105 people who did not have the disease.
Markers of inflammation and oxidative stress in semen were twice higher in men with the covid-19 disease compared to the control group. The authors also found significantly lower sperm concentration and motility and significantly more spermatozoa with altered shape in the covid-affected participants.
“These results are the first direct experimental evidence that the male reproductive system can be targeted by Covid-19,” they conclude. They note that the observed changes correspond to a condition of “oligoasthenoteratospermia, which is one of the most common causes of hypofertility in men.”
No evidence at this time
However, experts who were not involved in the study cautioned that more research is needed before conclusions can be drawn. “Men should not be overly concerned. There is currently no firm evidence of long-term damage to sperm or male reproductive potential from Covid-19,” said Alison Campbell, head of embryology at the specialty clinic group Care Fertility.
Fever can have a negative impact on sperm production, regardless of the disease that caused it.
The authors themselves note that one hypothesis is that the observed results may be due to the treatments some patients receive, particularly corticosteroids, antiviral drugs, as some studies have shown a negative impact on sperm quality. Forty-four percent of participants in the Covid group had been treated with corticosteroids and 69% with antiviral drugs.
Regardless of the effect of the coronavirus, “we already know that fever can have a negative impact on sperm production, regardless of the disease that caused it,” says Allan Pacey, a male fertility specialist at the University of Sheffield (UK).