SAN FRANCISCO (KGO) -- A new study involving more than 2,000 couples trying to conceive shows men who got coronavirus had fertility issues after infection.
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A research paper funded by the National Institutes of Health shows men who tested positive for COVID-19 within 60 days of their partner's cycle were 18% less likely to conceive during that cycle.
"Our hypothesis is that getting COVID and potentially having a fever associated with COVID could affect spermatic genesis, which is the process by which sperm develops. Other studies have shown that fever, regardless of whether is COVID or from something else, can affect sperm quality for the next couple of months," said Amelia Wesselink, PhD, Co-author & Research Assistant Professor of Epidemiology at the Boston University School of Public Health.
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Dr. Wesselink was the co-author of this study. Her team followed 2,100 couples between 21 to 45 years old for roughly a year, 75% of them getting vaccinated during this time frame.
Luz Pena: "Did you notice any sort of fertility impacts in women who got COVID or who got vaccinated?"
Dr. Wesselink: "In our study we did not observe any effects of either vaccination or infection in women. That was regardless of time since vaccination or time since infection. We looked at the different brands of vaccination, and really across the board, very little association of either exposure with fertility in women."
They also didn't find any fertility setbacks in men who got vaccinated.
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Dr. Michael Eisenberg, Director of the Male Reproductive Medicine and Surgery program, at Stanford explains why the body's temperature is key.
Luz Pena: "Why is fever playing a role in this?"
Dr. Eisenberg: "As fever responds to infection as the body does normally, it can slow down sperm production and is sort of toxic for sperm."
Dr. Eisenberg also highlighted men who get COVID could also experience challenges beyond fertility within those 60 days after infection.
"There can be impacts not just in sperm production but also to sexual functions too. We are also seeing links to erectile dysfunction in some of these more acute episodes. All of those probably do contribute, to some extent, to this lower change of pregnancy in that first window," said Dr. Eisenberg.
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According to this study, that decline in fertility among men after getting COVID did get better after those 60 days.
These experts emphasized the importance of getting vaccinated to prevent these setbacks if you want to conceive.