Publications, shared thousands of times, on social networks claim that Pfizer’s vaccine against Covid-19 could cause infertility in women. But several scientists explained that this hypothesis was to date scientifically unfounded and even almost impossible.
“Former head of respiratory research at Pfizer, Dr Yeadon, and lung specialist and former head of the MS department, Dr Wodarg; have filed a petition with the EAJ warning that COVID vaccines can cause female STERILITY“.
Publications, shared thousands of times, on social networks claim that Pfizer’s vaccine against Covid-19 could cause infertility in women. But several scientists explained that this hypothesis was to date scientifically unfounded and even almost impossible. so Pfizer’s vaccine against Covid-19 could not cause infertility in women .
The placenta is the organ that allows exchanges between the fetus and the mother. It is formed during pregnancy and is expelled at the time of childbirth.
Similar claims are also circulating in German and Portuguese. The publications mentioned in particular Michael Yeadon, a former researcher at Pfizer, who left the company in 2011 (according to his LinkedIn profile); after having worked there on allergies and respiratory research.
The publications claim that one of the vaccines against Sars-Cov-2, the virus that causes Covid-19, can cause the immune system to attack a protein involved in the development of the placenta, syncytin-1, thus leading to infertility in women.
According to this theory, because the vaccine teaches the body to fight a protein of the virus (the Spike protein) by producing antibodies; these could also attack syncytin-1 because it looks like the Spike protein of Sars-CoV-2.
It comes from this article (page 5), In passage XI mentioned the question of the syncytin-1 protein, dated December 1; signed by Michael Yeadon and a certain Wolfgang Wodarg, presented as a doctor. 43 pages long, the text is addressed to the European Medicines Agency (EMA); and intends to list the uncertainties and potential dangers linked to the Pfizer / BioNTech vaccine, according to its authors.
This vaccine has received the green light from health authorities in several countries. It began to be administered on December 8 in the United Kingdom while the United States is to begin vaccination on December 14.
It can be noted that the text itself states that “there is no indication” in the direction of anti-Spike protein antibodies “which would also act as an anti-Syncytin-1 antibody”.
He continues: “However if this were to be the case, it would also prevent the formation of a placenta, which would result in the vaccinated women being infertile.”
We can see, from the outset, that this is only a simple guess.
A theory that nothing comes to support to date and which is even more than improbable according to several specialists.
Like all vaccines, the goal of Pfizer’s vaccine is to teach the body to recognize the Sars-CoV-2 virus in order to fight it using antibodies. The idea is to “mimic” a real infection but with a harmless molecule.
The specificity of this vaccine is to use the technique known as messenger RNA or mRNA.
“The mRNA vaccine provides the body with a component that tells human cells how to synthesize a protein“, the Spike protein, which, by spiking on the surface of Sars-CoV-2, allows it to enter the cell and attacks it, explains Dansantila Golemi-Kotra, associate professor of microbiology at York University in Canada.
Concretely, we inject a so-called messenger RNA molecule which will “ask” our cells to manufacture this Spike protein, harmless as such.
By recognizing it, the body will trigger an immune response and produce antibodies capable of neutralizing Sars-CoV-2 if it were to infect us.
Could these antibodies “be wrong” and attack another type of protein that looks like it?
“The concern that antibodies targeting Spike proteins could attack the syncytin-1 protein of the placenta because the spike protein of the novel coronavirus shares a very short amino acid sequence with it, is very weak“, according to Dansantila Golemi-Kotra.
The body’s identification of the Spike protein “s rarely limited to a single short sequence of amino acids; explains the scientist.
Sanjay Mishra, the research fellow at Vanderbilt University in Nashville, USA, agrees: “A large number of studies have shown that infection with Sars-Cov-2 results in the production of antibodies against the protein peak virus. Thus, one can legitimately expect that a vaccination inducing the production of the viral protein will also direct the antibodies against this viral peak protein and nothing else“.
Even if sequences are common between the two proteins, “these sequences reorganize themselves in the proteins (…) to give a kind of three-dimensional shape. It is this shape that is recognized by the antibodies”, he explains.
Finally, underlines Annette Beck-Sickinger, professor at the University of Leipzig in Germany: “if the argument concerning syncytin were true, every woman infected with the virus would therefore have become sterile, but this is not the case. “
People infected with Sars-Cov-2″ have all produced anti-spike antibodies and there is no recovery indicating that it prevented women from getting pregnant, “abounds Frédéric Altare.
“If that does not happen naturally with the virus, there is no reason that it should do with something else”, insists the specialist.
“It has been suggested that the anti-Covid vaccines will cause infertility because of a short amino acid sequence in the spike protein of Sars-CoV-2; common to the syncytin-1 protein. But this sequence is too short – 4 amino acids in common – to plausibly risk generating an autoimmune reaction, “said Dervila Keane, spokesperson for Pfizer.
“There is no data to suggest that the Pfizer / BioNTech vaccine candidate causes infertility,” she continued.
More than 140 pages of data were released on Dec. 8 by Pfizer and the U.S. drug agency, FDA, detailing observations from clinical trials of the vaccine. On the 10th, these results were published in the medical journal New England Journal of Medicine.