I have gotten many questions from viewers asking whether a covid-19 infection or vaccination
can lead to male infertility.
There are scientific reasons to be concerned about covid infection affecting male fertility.
In this episode, I will review what we know about Covid 19 and male fertility.
Stay tuned.
Men produce sperm continuously all through their lives.
Sperm are produced in the testicles and it takes about three months from when sperm are
first created and when you can finally see them when a man ejaculates.
This is one of the reasons why it is very difficult to study the impact of any factor
on sperm production.
Another reason is that there is a tremendous amount of variation in sperm production from
day to day.
Watch this video for more information about that.
There are many things that can temporarily lower sperm production.
For example, if a man gets a fever or becomes severely ill for any reason, you can see his
sperm numbers will drop for a time afterward.
This may be due to harmful effects of heat on sperm production but it may be due to other
factors as well.
Is there any reason to suspect that Covid 19 infection might cause problems with sperm
production?
Yes.
In order to get into your cells, the SARS-CoV-2 virus needs two receptors.
One is called the ACE2 receptor.
The other is called the TMPRSS2 receptor.
Think of receptors as doorways on the surface of your cells.
Cells that don’t have these receptors, or have very low levels of them, will not let
the SARS CoV-2 virus inside.
The more receptors a cell has, the easier it is for the virus to get inside.
The lungs have a lot of these receptors which is why Covid 19 causes pneumonia in so many
people.
Where else can you find high amounts of these receptors?
Well, in men you can find lots of receptors in spermatogonia which are the cells from
which sperm are made, Sertoli cells, which help with the production of sperm and Leydig
cells which produce testosterone.
A Covid 19 infection could theoretically lower sperm production and testosterone production.
Some studies have found evidence of inflammation in the testicles of men who died from Covid
19.
One study compared 14 men with mild symptoms of COVID-19, 4 with moderate symptoms, and
14 healthy control men.
They found lower sperm numbers and lower sperm movement in the men with Covid compared to
healthy men
Another study of 23 men examined their semen about a month after they tested positive for
Covid-19 and did not find any impact on sperm numbers, movement or appearance.
In a 3rd study of 12 men with Covid, 11 had moderate symptoms.
A semen analysis done about 2 and a half months later was normal in 8 out of the 12.
Hormone changes in men were found.
Finally, a fourth study of 30 men showed that Covid infected men had a higher percentage
of abnormal appearing sperm.
None of these studies conclusively prove that male Covid infection caused their sperm problems.
Although some abnormal results were found, these could have been due to other factors
besides the virus, such as fever, natural variability, treatments given for Covid or
difference in the men themselves, like obesity.
Even if the abnormal results were due specifically to the SARS CoV-2 virus, we don’t know if
these changes were temporary or permanent.
Finally, even if we believe that the virus causes these problems and we think they are
permanent, we still don’t know if they are severe enough to affect male fertility.
As you can see there are many unknowns about Covid 19 infection and male fertility but
there are valid scientific reasons to be concerned.
There are no valid scientific concerns about Covid vaccination and male fertility.
A study performed here in the USA recruited healthy young men to give a semen sample before
and after receiving two doses of either the Pfizer or Moderna vaccines.
They found that the average sperm concentration and the total number of moving sperm actually
increased after vaccination.
Remember, there is much variability in sperm numbers so this does not prove that vaccination
improved their sperm quality.
It does make it very unlikely that vaccination has any negative effect.
Bottom line.
Infections may cause problems with sperm production.
Vaccinations do not.
Vaccination has been proven to significantly reduce the risk of infection in both men and
women.
Our InfertilityTV recommendation is this.
Don’t take the chance.
Get vaccinated as soon as vaccines are available to you.