Effect of BNT162b2 mRNA COVID-19 vaccine on human semen

Italian scientists recently analyzed the effect of the mRNA-based coronavirus disease 2019 (COVID-19) vaccine on the quality of semen in adult men. No significant differences were observed in sperm quality and semen plasma parameters (oxidative stress, inflammation, electrolyte levels) after vaccination.The study was published in the journal Andrology..

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the COVID-19 pandemic, is a deadly member of the human beta coronavirus family. The virus is known to cause a variety of symptoms in infected individuals, from mild respiratory symptoms to severe pneumonia, respiratory failure and death. Apart from infections of the respiratory tract, the virus can impair the function of other organs such as the heart, liver, gastrointestinal tract, kidneys, and brain.

In a few studies, people infected with SARS-CoV-2 may develop testicular abnormalities such as structural changes in testicular cells, loss of basement membrane and seminiferous tubule integrity, and infiltration of pro-inflammatory mediators. It is shown that there is. However, there are currently no comprehensive data available to understand the effects of the COVID-19 vaccine on reproductive function.

In the current study, scientists evaluated the effects of the mRNA-based COVID-19 vaccine BNT162b2 (Pfizer / BioNTech) on human semen.

Research design

The study was conducted on a total of 47 adult men who received a double Pfizer vaccine regimen between February and July 2021. Semen samples were collected from participants before the first vaccination and 70 days after the second vaccination. dose.

All semen samples were analyzed to measure sperm concentration, motility, and morphology. In addition, the concentrations of reactive oxygen metabolites, electrolytes, and interleukin 6 (IL-6) were determined using serum samples.

Important findings

Of all registered participants, 10% reported moderate smoking and 38% reported social drinking. None of the participants reported systemic side effects such as fever, allergies, or swollen lymph nodes.

No significant changes were observed in semen volume, sperm concentration, motility, and morphology in participants after COVID-19 vaccination compared to before vaccination.

Another series of experiments was performed on male participants with low sperm counts or impaired sperm motility. No significant differences in sperm parameters were observed in these participants after vaccination. However, sperm parameters tended to improve in these participants.

As with sperm parameters, no significant changes in electrolytes (calcium, chlorine, potassium, magnesium, and sodium), reactive oxygen metabolites, and IL-6 levels were observed among participants after vaccination.

In addition, no significant correlation was observed between the sperm parameters tested and the electrolytes and reactive oxygen metabolites of IL-6.

Significance of research

Research results show that the mRNA-based COVID-19 vaccine (Pfizer) does not adversely affect sperm quality. In addition, the vaccine does not alter the levels of electrolytes (an indicator of good cell membrane activity), reactive oxygen metabolites (an indicator of oxidative stress), and IL-6 (an indicator of inflammation).

Overall, this study emphasizes that the COVID-19 vaccine can be safely used among men. However, this study included only a few men with poor sperm quality who were prone to worsening sperm parameters. In addition, survey participants belong to a particular population, so survey results cannot be generalized to the global population.