Evidence Points to Safety of COVID-19 Vaccines for Pregnant People


SciCheck Digest

Clinical trials and medical studies have indicated that the COVID-19 vaccines are safe for pregnant people. But online posts misrepresent unverified reports submitted to vaccine monitoring systems in the U.S. and Europe to misleadingly suggest “920 women” lost babies because they received COVID-19 vaccines.

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The United States, the United Kingdom and the European Union each have systems for reporting side effects that may have been caused by a vaccine.

The U.S. has the Vaccine Adverse Event Reporting System, or VAERS; the U.K. has Yellow Card; and the EU has EudraVigilance.

Anyone can submit a report to those systems, even if it’s not clear that the vaccine caused the problem. Public health officials use those submissions to detect patterns that may indicate potential safety issues or side effects.

All three systems clearly state that the information they record may not actually be related to the administered vaccine, but could, instead, be coincidental.

Despite that fact, social media posts present information from these systems as evidence to support an unsubstantiated claim that COVID-19 vaccines harm pregnancies. One headline that was shared on Instagram as a screenshot meme has been liked more than 72,000 times. It says: “920 Women Lose Their Unborn Babies After Getting Vaccinated.”

That post was shared by Shannon Kroner, who uses the title of doctor, although The Chicago School of Professional Psychology, where she got her degree, confirmed to us in a phone interview that she received a Ph.D. in psychology, not a medical degree. Kroner runs an organization that advocates for the right to use religious exemptions to avoid childhood vaccines. She did not return a call seeking comment about the claim.

The headline she shared came from a conservative website called The True Defender, which published a story taken largely from a British website that published the original claim and describes itself as an alternative to “the lying mainstream media.”

The original claim cited unverified reports submitted to VAERS, Yellow Card and EudraVigilance.

As we said, submissions to those systems are unverified and the reported issue is not necessarily related to the vaccine.

The VAERS website says: “A report to VAERS generally does not prove that the identified vaccine(s) caused the adverse event described. It only confirms that the reported event occurred sometime after vaccine was given. No proof that the event was caused by the vaccine is required in order for VAERS to accept the report. VAERS accepts all reports without judging whether the event was caused by the vaccine.”

Similarly, the U.K.’s Medicines & Healthcare products Regulatory Agency, which runs Yellow Card, explained in a recent report: “The nature of Yellow Card reporting means that reported events are not always proven side effects. Some events may have happened anyway, regardless of vaccination. This is particularly the case when millions of people are vaccinated, and especially when most vaccines are being given to the most elderly people and people who have underlying illness.”

And the site for EudraVigilance, says (emphasis theirs): “The information on this website relates to suspected side effects, in other words, effects that have been observed following administration of, or treatment with, a medicine. However, these suspected side effects may not be related to or caused by the medicine.”

It’s also worth noting that, in the case of the VAERS data cited in the meme, most of the reported miscarriages happened in the first trimester. That’s the most common time for a miscarriage to happen and, according to the March of Dimes and the Mayo Clinic, about 10% to 20% of known pregnancies end in miscarriage. The actual number is probably higher, though, since many women don’t know they’re pregnant at that early stage.

More importantly, there is no evidence that the COVID-19 vaccines pose a risk to pregnancy.

Both the CDC and the American College of Obstetricians and Gynecologists have noted that data is limited on this issue, but there have been no indications that the vaccines are dangerous to pregnant people. They both also note that animal studies showed no safety concerns for the pregnancy or the fetus.

Pregnant people were excluded from the clinical trials for the three vaccines available in the U.S., but some pregnancies occurred over the course of the trials and their outcomes were tracked. In the Pfizer/BioNTech trial, 23 pregnancies were reported with no miscarriages in the group that received the vaccine and one in the placebo group. Similarly, in the Moderna trial, there were 13 pregnancies and no miscarriages reported in the group that got the vaccine, with one miscarriage in the placebo group. And in the Johnson & Johnson trial, there were eight pregnancies and two miscarriages — one each in the vaccine and placebo groups.

Since then, studies have suggested that the vaccines are safe during pregnancy. An article published in the New England Journal of Medicine in April evaluated data from more than 35,000 pregnant people who received the Pfizer or Moderna vaccines and submitted reports to three different reporting systems — including VAERS. While it called for further study, the preliminary report found that there was no increased risk during pregnancy for those who received the vaccines.

Another study, published in the journal Obstetrics & Gynecology in May, found no evidence that those two vaccines would damage the placenta during pregnancy.

“[T]hese findings add to the growing literature supporting the safety of SARS-CoV-2 vaccination in pregnancy,” it concluded.

Public health officials continue to gather information about the effect of the vaccines on pregnancy to capture any safety signals that might crop up.

Conversely, there is evidence that pregnant people are at an increased risk for pregnancy complications if they contract COVID-19. While the overall risk of severe illness is low, the Centers for Disease Control and Prevention warns that “pregnant people with COVID-19 are at increased risk of preterm birth and might be at increased risk of other adverse pregnancy outcomes compared with pregnant women without COVID-19.”

Still, misinformation peddlers have continued to spread unsupported claims tying the vaccines to fertility issues. For more, see our SciCheck stories, “No Evidence Vaccines Impact Fertility” and “No Scientific Basis for Vaccine ‘Shedding’ Claims.”

Editor’s note: SciCheck’s COVID-19/Vaccination Project is made possible by a grant from the Robert Wood Johnson Foundation. The foundation has no control over our editorial decisions, and the views expressed in our articles do not necessarily reflect the views of the foundation. The goal of the project is to increase exposure to accurate information about COVID-19 and vaccines, while decreasing the impact of misinformation.


Vaccine Adverse Event Reporting System. Frequently Asked Questions. Vaers.hhs.gov. Accessed 8 Jun 2021.

Yellow Card. About Yellow Card. Yellowcard.mhra.gov.uk. Accessed 8 Jun 2021.

EudraVigilance. How to report a side effect. Adrreports.eu. Accessed 8 Jun 2021.

Abalos, Victor. Spokesman, The Chicago School of Professional Psychology. Telephone interview with FactCheck.org. 10 Jun 2021.

920 Women Lose Their Unborn Babies After Getting Vaccinated.” Thetruedefender.com. 3 Jun 2021.

Are the Covid Vaccines safe for use during pregnancy? – We doubt the 920 Women who’ve lost their baby due to them think so.” Dailyexpose.co.uk. 29 May 2021.

Vaccine Adverse Event Reporting System. Guide to Interpreting VAERS Data. Vaers.hhs.gov. Accessed 8 Jun 2021.

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Shimabukuro, Tom T., et al. “Preliminary Findings of mRNA Covid-19 Vaccine Safety in Pregnant Persons.” The New England Journal of Medicine. 21 Apr 2021.

Shanes, Elisheva D., et al. “Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Vaccination in Pregnancy.” Obstetrics & Gynecology. 11 May 2021.

Centers for Disease Control and Prevention. COVID-19 Vaccines While Pregnant or Breastfeeding. Updated 9 Jun 2021.

Jaramillo, Catalina. “No Evidence Vaccines Impact Fertility.” FactCheck.org. Updated 3 Mar 2021.

Jaramillo, Catalina. “No Scientific Basis for Vaccine ‘Shedding’ Claims.” FactCheck.org. 11 May 2021.

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