Covid infections can have a negative impact on sperm quality for up to three months, according to newly released research which found that the coronavirus reduces sperm count by up to 37% while also slowing its movement.
The study, which hasn’t been peer reviewed yet, was conducted by academics in Belgium on 120 men who had suffered symptomatic cases of Covid, and was published in the Fertility and Sterility journal on Monday.
Samples from all of the study participants, who had an average age of 35 and had been symptom-free for an average of 52 days by the time the samples were taken, showed a 37% reduction in their sperm count following infection by the virus.
The impact of Covid on male fertility lasted for three months, the researchers found, by which time the sperm count had returned to a normal level. Alongside the reduced sperm count, there was a 60% drop in the ability of semen to move.
“Couples with a desire for pregnancy should be warned that sperm quality after Covid-19 infection can be suboptimal,” the study concluded, although the scientists accepted that more research was required to look at the long-term impact on fertility.
The situation reflects what’s already known about other viruses, like influenza, which are known to damage sperm. As regards the flu, scientists have previously blamed the adverse impact on higher body temperatures caused by virus-induced fevers. However, with Covid, the study suggested that fever was not to blame, rather that the knock-on sperm issues are due to the body’s immune response to the virus.
Tests conducted on the individuals involved in the study saw a correlation between higher concentrations of Covid antibodies in the blood of patients and reduced sperm function, known as temporary sperm dysfunction.
Despite the negative effects of Covid on sperm count, researchers noted there is “strong evidence” that the virus can not be sexually transmitted through the semen of those who have recently recovered from infection.