COVID-19 Vaccine and Fertility: Demystifying the Myths (2025)

Common Concerns

Reports about the alleged negative effects of COVID-19 vaccines on fertility continue to circulate on Western social media, including claims of reduced fertility and pregnancy complications. These claims appear in posts on Twitter, Facebook, and Reddit, and have also been disseminated through videos on YouTube. In response to these claims, numerous studies conducted between 2020 and 2024 found no link between vaccinations and reproductive health issues.

How COVID-19 Vaccines Work

The COVID-19 vaccines created by Pfizer, Moderna, and other biotechnology companies are based on messenger RNA (mRNA). This technology allows the muscle cells of the body to produce the specific spike (S) protein of the SARS-CoV-2 virus, which is the causative agent of COVID-19. In response, the human immune system actively begins to produce antibodies against this protein, thus providing protection against infection.

Demystifying the Vaccine's Effect on the Placenta

A common myth is the claim that the S protein of the coronavirus is similar to the glycoprotein syncytin-1, which plays a key role in the attachment of the placenta to the uterine wall in women. This raises concerns that the antibodies produced in response to vaccination might attack syncytin-1, thereby interfering with the implantation process. However, these speculations are not backed by scientific evidence.

Studies published in Nature Communications, JAMA, and The Lancet in 2023 and 2024 show that vaccinated women and men do not experience a decrease in fertility compared to unvaccinated women and men.

Virology professor Ian Jones from the University of Reading (UK) explains that there is indeed a slight structural similarity between the S protein of SARS-CoV-2 and syncytin-1. However, this similarity is so minor that the likelihood of undesirable cross-reactive effects is extremely low. Furthermore, new research conducted by the University of Oxford in 2024 has proven that antibodies following COVID-19 vaccination do not affect the embryo implantation processes.

Expert Opinions

Mary Jane Minkin, an obstetrician-gynecologist and clinical professor of obstetrics and gynecology at Yale School of Medicine (USA), also emphasizes that the human immune system cannot confuse the S protein of the coronavirus with syncytin-1. She explains, “Yes, they share a slight structural similarity, but only in a small part of the molecule. This is not enough to trigger an unwanted immune response against the placental protein.”

Additionally, a study published in the British Medical Journal in 2024 showed that the rate of successful pregnancies among vaccinated women did not differ from that of unvaccinated women. Experts stress that the spread of misinformation can undermine confidence in vaccination, thereby jeopardizing public health.

In summary, allegations of a link between COVID-19 vaccination and fertility problems are not based on any scientific foundation. Two prominent experts, such as virology professor Ian Jones (University of Reading) and clinical professor of obstetrics and gynecology Mary Jane Minkin (Yale School of Medicine), agree that vaccines are safe and do not affect the ability to conceive a child.