Health Highlights: Jan. 29, 2021

Study Suggests COVID-19 Harms Men's Fertility, But Experts Question Findings

Severe COVID-19 might harm men's fertility by reducing the quality of their sperm, a new study says, but some experts were skeptical about the findings.

In the study, researchers analyzed semen from 84 men with COVID-19 and 105 uninfected men. Their semen was examined every 10 days for 60 days, CNN reported.

Compared to the uninfected men, those with COVID-19 had significant increases in inflammation and oxidative stress in sperm cells, and the virus was also tied to lowered sperm concentration, mobility and shape.

The differences grew with the severity of COVID-19, according to the study published in the journal Reproduction.

"This report provides the first direct evidence to date that COVID-19 infection impairs semen quality and male reproductive potential," lead researcher Behzad Hajizadeh Maleki, a doctoral student at Justus Liebig University in Giessen, Germany, and colleagues wrote, CNN reported.

But experts who weren't involved in the study expressed concerns about the findings.

"I need to raise a strong note of caution in their interpretation of this data. For example, the authors state that their data demonstrates that 'COVID-19 infection causes significant impairments of male reproductive function,' yet it only actually shows an association," Allan Pacey, professor of reproductive endocrinology and andrology at the University of Sheffield in South Yorkshire, U.K., told CNN.

"Being ill from any virus such as flu can temporarily drop your sperm count [sometimes to zero] for a few weeks or months. This makes it difficult to work out how much of the reductions observed in this study were specific to COVID-19 rather than just from being ill," Channa Jayasena, a consultant in reproductive endocrinology and andrology at Imperial College London, U.K., told CNN.

It's "important to note that there is no evidence of COVID-19 virus in the semen and that there is no evidence that virus can be transmitted via semen," Alison Murdoch, head of the Newcastle Fertility Centre at the International Centre for Life, Newcastle University, U.K., told CNN.