Covid-19 may affect sperm quality and decrease fertility in men, according to a new study based on experimental evidence.
The viral disease, which has spread across the globe and kills almost 2.2 million people, can lead to increased sperm death, inflammation and so-called oxidative stress, researchers reported on Friday in the journal Reproduction.
“These results provide the first direct experimental evidence that the male reproductive system could be attacked and damaged by Covid-19,” the authors concluded.
However, experts who commented on the research said the virus’ ability to affect fertility in men remains unproven.
Covid-19 causes respiratory illness, especially in the elderly and people with underlying medical problems.
The world has seen more than 100 million confirmed cases since the disease emerged in central China in late 2019.
The disease is transmitted through respiratory droplets and affects the lungs, kidneys, intestines and heart.
It can also infect male reproductive organs, impair sperm development, and disrupt reproductive hormones, as previous studies have shown. The same receptors that the virus uses to access lung tissue are also in the testes.
However, the effects of the virus on male fertility remained unclear.
Behzad Hajizadeh Maleki and Bakhtyar Tartibian from the Justus Liebig University in Germany were looking for biological markers that could indicate a negative impact on fertility.
The analysis, performed at 84-day intervals for 60 days on 84 men with Covid-19, was compared with data for 105 healthy men.
In Covid-19 patients, sperm showed a significant increase in markers of inflammation and oxidative stress, a chemical imbalance that can damage DNA and proteins in the body.
“These sperm effects are linked to lower sperm quality and decreased fertility potential,” Maleki said in a statement.
“Although these effects tended to improve over time, they remained significantly and abnormally higher in Covid-19 patients.”
The more severe the disease, the greater the changes, he added.
The male reproductive system “should be viewed as a vulnerable route to Covid-19 infection and declared a high-risk organ by the World Health Organization,” said Maleki.
Experts not involved in the study welcomed the research but warned that more was needed before firm conclusions could be drawn.
“Men shouldn’t be unduly alarmed,” noted Alison Campbell, director of embryology for CARE Fertility Group in the UK.
“There is currently no definitive evidence of permanent damage to sperm or male reproductive potential from Covid-19,” she told the London-based Science Media Center.
The results may have been skewed by the fact that men who recovered from Covid were treated with corticosteroids and antiviral therapies, while the control group did not.
Allan Pacey, a male reproductive medicine specialist at the University of Sheffield, was “very careful” about how the data was interpreted.
Some of the indicators of decreased sperm quality could be due to factors other than Covid-19, he said, noting that more men in the Covid-19 group were overweight.
The simple fact that only one group – regardless of the cause – is very sick also needs to be considered, he added.
“We already know that a febrile illness can affect sperm production regardless of what caused it.”
(Except for the headline, this story was not edited by GossipMantri staff and posted from a syndicated feed.)