“This report provides the first direct evidence to date that COVID-19 infection impairs semen quality and male reproductive potential,” said the study.
However, experts not involved in the study were immediately skeptical of the report’s conclusion and urged caution in over-generalizing the survey results.
“I need to raise a strong note of caution in their interpretation of these data. For example, the authors claim that their data demonstrate that ‘COVID-19 infection causes significant damage to male reproductive function’, although it only really shows an association,” said Allan Pacey, professor of andrology at the University of Sheffield in South Yorkshire, UK, by email.
“Being sick from any virus, like the flu, can temporarily lower your sperm count (sometimes to zero) for a few weeks or months. This makes it difficult to find out how much of the reductions observed in this study were specific to COVID-19, rather than just being sick, “said Dr. Channa Jayasena, a consultant in reproductive endocrinology and andrology at Imperial College London, via email.
In addition, “it is important to note that there is no evidence of the Covid-19 virus in semen and that there is no evidence that the virus can be transmitted via semen,” said Alison Murdoch, who runs the Newcastle Fertility Center at the International Center for Life, Newcastle University, UK, by email.
Small study of 84 men
The study compared 105 fertile men without Covid-19 with 84 fertile men diagnosed with coronavirus and analyzed their semen at intervals of 10 days for 60 days.
Compared to healthy men without Covid-19, the study found a significant increase in inflammation and oxidative stress in sperm cells belonging to men with Covid-19. The concentration, mobility and shape of your sperm were also negatively affected by the virus.
The differences increased with the severity of the disease, the study concluded.
“These effects on sperm cells are associated with poorer sperm quality and reduced fertility potential. Although these effects tend to improve over time, they have remained significantly and abnormally greater in patients with COVID-19, and the magnitude of these changes has also increased. were related to disease severity, “said principal investigator Behzad Hajizadeh Maleki, a doctoral student at Justus Liebig University Giessen in Hesse, Germany, in a statement.
There were also much higher levels of ACE2 enzyme activity in men with Covid, the study found. ACE2, or angiotensin-converting enzyme 2, is the protein that provides the entry point for the new coronavirus to connect and infect a wide range of human cells
However, it is not surprising that Covid-19 can impact the male reproductive system because ACE2 receptors, or “the same receptors that the virus uses to gain access to lung tissue, are also found in the testes,” said Pacey, who also is editor in chief of Human Fertility magazine.
A constant concern
“Since the beginning of the Covid-19 pandemic, there has been an understandable (but theoretical) concern about whether this coronavirus could have a detrimental impact on the fertility of men who are infected,” said Pacey.
After reviewing about 14 published studies on the subject, Pacey said he concluded that “any measurable effect of coronavirus on male fertility was probably only mild and temporary”.
The findings of this study, he added, may be due to other factors, such as the use of drugs to treat the virus, which the authors also recognized in the study.
“So, all I see in this data set is possible differences in sperm quality between men who are sick with febrile illness (fever) and those who were fine. We already know that a febrile illness can affect sperm production, regardless of what caused it, “said Pacey.
Sheena Lewis, professor emeritus at Queen’s University Belfast, Ireland, shared similar thoughts by email: “My concern is that men with COVID had substantially more body weight and were on various therapeutic treatments.
“We know that obesity alone reduces the quality of sperm. COVID treatments may also have affected the sperm quality of these men, rather than COVID itself,” said Lewis.
“Thus, long-term studies are needed before the testicles are considered a high-risk organ specific to Covid-19,” said Murdoch of Newcastle.