One of the most repeated myths of COVID-19 vaccination concerns fertility. Do the COVID-19 vaccines cause swollen testicles, erectile dysfunction (ED) and lower sperm count? No, but COVID-19 infection can cause each of these issues.
Nebraska Medicine Urologist Chris Deibert, MD, who treats ED and other men's health conditions, walks through the research on this issue.
Swollen testicles
After COVID-19 infection
Many people with testicles will experience testicular swelling or swelling of the epididymis after symptomatic COVID-19 infection. A recent review estimates that "10% to 22% of men with acute COVID-19 infection develop orchitis or epididymo-orchitis." Orchitis is the medical term for testicular swelling or inflammation. COVID-19 isn't the first infection to cause swollen testicles. A lot of infections can cause testicular swelling, including E. coli bacteria, gonorrhea, chlamydia and mumps.
After vaccination
Except for unconfirmed reports on social media, there's no evidence that the COVID-19 vaccination is linked to testicular swelling. It's important to treat personal stories differently than scientific research. Dr. Deibert says he hasn't seen any evidence locally or nationally linking swollen testicles and COVID-19 vaccination. If you're curious about how mRNA vaccination works, find out how long spike proteins last in the body.
Erectile dysfunction
After COVID-19 infection
A small, self-reported survey of Italian men suggests a link between ED and COVID-19 infection. This study found that reported ED was higher in COVID-19 positive people. People reporting erectile dysfunction with prior COVID-19 infection was 28% while those with no COVID-19 infection was 9%.
It appears that the virus can go to all parts of the body when someone is symptomatically ill. Dead virus has been found in erectile tissues after severe, acute infection, but it's not totally clear if or how the virus causes erection issues.
Researchers found viral particles in penis biopsies, taken from two people who previously had COVID-19. Both had "normal erectile function" before their COVID-19 infections. See the images here. The researchers did not find viral particles in penis biopsies of two other people with no history of COVID-19 infection.
After vaccination
Dr. Deibert has not seen any patients who developed erectile issues after vaccination alone, and he hasn’t heard any reports of that happening. After reviewing research databases, the American Society for Reproductive Medicine says, "No evidence of any connection between COVID-19 vaccines and male infertility was found, but there were 50 reviews, 17 commentaries/letters to editors and nine original articles on how COVID-19 disease could possibly impact male fertility."
Sperm count
After COVID-19 infection
COVID-19 infection can lower sperm counts, at least temporarily. A small study compared the median sperm counts of COVID-19-positive men with sperm counts of COVID-19-negative men. The median sperm count of those without infection was 21.5 million and with infection was 12.5 million.
After vaccination
There is some reassuring data that the vaccine doesn't change sperm count.
A small, peer-reviewed study measured 45 people's sperm counts before and after COVID-19 mRNA vaccination. The study reported that there were "no significant decreases in any sperm parameter among this small cohort of healthy men" after two doses of either Moderna or Pfizer vaccines.
In summary, COVID-19 vaccines do not affect men’s fertility, but COVID-19 infection does. To sum up what we know so far:
- COVID-19 vaccines are not linked to swollen testicles, erectile dysfunction or lower sperm counts
- Billions of COVID-19 vaccines have been given worldwide. If a link between fertility and vaccination exists, where is the clinical evidence?
- COVID-19 infection can cause swollen testicles, erectile dysfunction and lower sperm counts