According to a new study which is based on experimental evidence, Covid-19 could harm sperm quality and decrease fertility in men.
The viral disease — which has swept the globe, claiming nearly 2.2 million lives — can cause increased sperm cell death, inflammation and so-called oxidative stress, according to a new study published Friday in the journal Reproduction.
The authors concluded, “These findings provide the first direct experimental evidence that the male reproductive system could be targeted and damaged by Covid-19,”
Commenting on the study, authors said the virus’s potential to compromise fertility in men remains unproven.
Covid-19 causes respiratory disease, especially in the elderly and those with underlying medical issues.
Since the disease originated in central China at the end of 2019, the world has seen more than 100 million confirmed cases.
The disease, transmitted through respiratory droplets, attacks the lungs, kidneys, bowels, and heart.
Earlier studies have shown it can also infect male reproductive organs, impair sperm cell development and disrupt reproductive hormones. Often present in the testicles are the same receptors the virus uses to enter lung tissue.
However, the impact of the virus on men’s ability to reproduce remains unknown.
Behzad Hajizadeh Maleki and Bakhtyar Tartibian from the University of Justus-Liebig in Germany were looking for biological markers that could have a detrimental effect on fertility.
In 84 men with Covid-19, a study conducted at 10-day intervals for 60 days was compared to results for 105 healthy men.
Sperm cells showed a large increase in signs of inflammation and oxidative stress in the Covid-19 patients, a chemical imbalance that can harm the body’s DNA and proteins.
‘Strong caution note’
“These effects on sperm cells are associated with lower sperm quality and reduced 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.”
He said, the more serious the disorder, the bigger the changes.
Maleki said that the male reproductive system “should be considered a vulnerable route of Covid-19 infection and declared a high-risk organ by the World Health Organisation,”
Experts not involved in the research welcomed the study but cautioned that before drawing hard and fast conclusions, more was required.
“Men should not be unduly alarmed,” noted Alison Campbell, CARE Fertility Group’s director of embryology in Britain.
“There is currently no definitive evidence of long-lasting damage caused by Covid-19, to sperm or male reproductive potential,” she told the London-based Science Media Centre.
The findings may have been skewed, she said, by the fact that corticosteroids and antiviral therapies were treated by men suffering from Covid, while the control group was not.
Allan Pacey, a specialist in male reproductive medicine at the University of Sheffield, gave a “stong note of caution” on the interpretation of the results.
Apart from Covid-19, some of the measures of decreased sperm quality may be due to variables, he said, noting that more men were overweight in the Covid-19 sample.
The simple fact that only one group was very sick — no matter the cause — also needed to be taken into account, he added.
“We already know that a febrile illness can impact on sperm production, regardless of what caused it.”