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COVID-19 vaccines not linked to infertility

By Kerry Goff

Carrie Michaels, a nurse practitioner in the Infectious Diseases Department at St. Jude Children’s Research Hospital, is pregnant with her first child. After speaking with her fertility specialist physician and obstetrician, Michaels felt comfortable about getting the COVID-19 vaccine for the health and safety of her and her unborn baby.

In addition to Carrie Michaels’ video testimonial above, view videos from Dylan Graetz, MD, Oncology and Global Pediatric Medicine, and Brittany Bedard, RN, Surgical Services, about why they got vaccinated during their pregnancies.

Walking down the hallways of St. Jude, Diego Hijano, MD, Infectious Diseases, often gets questions about the COVID-19 vaccine’s safety and side effects, and whether infertility is one of them. People are generally skeptical, especially when they may hear second-hand reports or misinterpreted information.

Hijano explained that the American College of Obstetrics and Gynecology has been a mainstay of information regarding the vaccine and concerns of infertility. Virtually all research outcomes have discredited infertility concerns. 

Hijano further sets the record straight on the scientific research to quell concerns many women and parents of daughters may have about the vaccine of any age group.

Unfounded fertility fears and misinformation have been spread before with other vaccines.

Vaccines, antibiotics, medications for high blood pressure or other conditions, do not undergo years of human trials to look for fertility concerns before they are made available publicly. Basically, drugs are studied in the lab to answer basic questions about safety, before moving to human studies to assess safety and efficacy. Once approved, they continue to be monitored for safety.

“Misinformation on the vaccines as a cause of infertility continues to be a major barrier for COVID-19 vaccination efforts everywhere. It is not about drug safety, but about scaring people away from the vaccine.” Hijano said. “In addition, this fear translates from mothers to daughters and results in vaccine hesitancy.”

Hijano explained that there are currently three specific myths related to COVID-19 vaccines and fertility. The first one claims that the vaccines cause infertility by generating antibodies that not only target the coronavirus spike protein, as designed, but also inadvertently react with a protein in the placenta called syncytin-1. The myth claims that the viral protein and human protein are so similar in structure that the protective antibodies against the coronavirus will also prevent the placenta from developing properly, causing infertility.

“This is false,” he explained. “Researchers from Yale compared the coronavirus’s spike protein to placental syncytin-1 and found no notable similarity between them.”

In addition, a study published in “Fertility and Sterility”, the official journal of the American Society for Reproductive Medicine reports showed that antibodies, either from the vaccine or from having had COVID-19, do not prevent early pregnancy development. Also, women have and continue to conceive after coronavirus infection and vaccination. 


I want to be a grandfather one day, so if I thought infertility could be an issue, I would not put my daughters in harm’s way. Their futures are very important to me and I trust the research. 

Diego Hijano, MD, Infectious Diseases


The second more recent myth is that the mRNA vaccines accumulate in the ovaries. Hijano explained that this is also false. He cites two studies from the European Medicines Agency’s research that shows “no accumulation of vaccine-related products in the ovaries.”

The third myth asserts that changes to the menstrual cycle observed after COVID-19 vaccination will persist and impair a woman’s ability to conceive. Temporary, short lived, menstrual changes have been reported after both mRNA and adenovirus vectored COVID-19 vaccines, as well as previously with other vaccines, suggesting that any possible connection is likely a result of the immune response to vaccination rather than a specific vaccine component. Furthermore, the menstrual cycle can be affected by immune activation in response to various stimuli, including viral infection, including COVID-19. One study showed that around 25% of women infected with SARS-CoV-2 experienced menstrual disruption.

“This effect is not unexpected as it has been observed with other vaccines and after infections. Immune cells play an important role in menstruation, so it is possible that the vaccine could temporarily alter that process, such as we temporarily have fever, or swollen lymph nodes after vaccination” Hijano said.

Finally, as these claims have been proven to be false, the message has shifted towards the unknown possibility of infertility, and other side effects, in the long term. More than a year of data for immunization against COVID-19 and decades of research show that side effects from vaccination generally occur within six weeks. There is no mechanism for which vaccines, or their components will cause health problems years after being given.

“The concept that vaccines need years of research comes from the need to vaccinate enough individuals to detect very rare side effects and not because these side effects appear many years after receiving the vaccine,” Hijano said.  “In the case of COVID-19 vaccines, with over 9.8 billion doses administered globally and over 530 million in the U.S. alone, no additional unexpected, rare side effects will be observed.”

“Claims linking COVID-19 vaccines to infertility are unfounded and have no scientific evidence supporting them,” Hijano said. “The best way to obtain factual information is to rely on scientific research. Relying on social media and general news reports can create confusion and actual false information.”

Beyond even the vaccine, Hijano said that it is important to point out that infertility is a common problem. There are well-known causes and risk factors, and there has never been a vaccine that has been linked with it.

Hijano is the father of two daughters, one is 13 and the other is 11. Both have now received the COVID-19 vaccine. Hijano makes it clear that he would not put his own daughters at risk if he was even remotely skeptical.

“Both of my daughters got the vaccine as soon as it was available for their age group,” he said. “My father passed before he could be a grandfather. He would have been a wonderful grandfather. I want to be a grandfather one day, so if I thought infertility could be an issue, I would not put my daughters in harm’s way. Their futures are very important to me, and I trust the research.” 


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