CLAIM
COVID-19 vaccines increase the risk of miscarriage and stillbirth
DETAILS
Factually inaccurate: The claim is contradicted by many scientific studies showing that COVID-19 vaccines are not associated with an increase in negative pregnancy outcomes.
TAKE THE KEY WITH YOU
Scientific studies have shown that COVID-19 vaccines do not cause miscarriage or stillbirth. Pharmacosurveillance databases such as VAERS cannot be used alone to establish a causal relationship between vaccinations and a medical condition. Health authorities and medical associations recommend pregnant women to be vaccinated against COVID-19.
FULL CLAIM: COVID-19 vaccines increase the risk of miscarriage and stillbirth
REVIEW
Misinformation about vaccines based on misleading representations of data from adverse event databases is still rife on social media. An example of this is a graph posted by Instagram users in March 2023 showing a sharp increase in miscarriages and stillbirths reported to the US Vaccine Adverse Events Reporting System (VAERS).
The post includes the hashtag #FauciForPrison, which refers to the former director of the US National Institute of Allergy and Infectious Diseases (NIAID) and senior medical adviser to the US President during the COVID-19 pandemic. Together, these elements implied that COVID- 19 vaccines were responsible for the surge in reports of miscarriage and stillbirth.
However, such claims are inaccurate and contradicted by scientific evidence that misuses VAERS data in a way that promotes misinformation about vaccines. This review explains why.
Scientific data shows that COVID-19 vaccines are safe for pregnant women
The first clinical trials conducted to approve the COVID-19 vaccines excluded pregnant women due to ethical and legal concerns[1]. This is common practice with new medicines and vaccines, but results in a lack of data on this population. However, this information gap has now been filled by later studies and there is now a wealth of data showing that pregnancy outcomes are similar between vaccinated and unvaccinated women.
In a retrospective study of more than 85,000 births in Canada, researchers found that COVID-19 vaccination did not increase the risk of adverse pregnancy outcomes such as stillbirth, preterm birth, or low gestational age at birth[2].
Another study of women who gave birth in England between March 2020 and July 2021 found no differences in the risk of stillbirth and other perinatal safety outcomes, such as: B. fetal abnormalities or small for gestational age[3].
Another study analyzed the risk of miscarriage or ectopic pregnancy in vaccinated women compared to unvaccinated women and to historical data from before the pandemic. They found that the COVID-19 vaccination was not associated with an increased risk of miscarriage and ectopic pregnancy[4]. A Swiss study comparing the rate of negative pregnancy outcomes in vaccinated women to historical data from before the pandemic came to similar conclusions[5].
Other studies went the opposite way. Instead of comparing how many women had a miscarriage between the vaccinated and unvaccinated categories, they compared how many women were recently vaccinated between the miscarriage and ongoing pregnancy categories. Consistent with all of the above results, they found no over-representation of vaccinated women in the miscarriage category. In other words, there was no connection between vaccination and miscarriage[6,7].
Systematic reviews of the available scientific literature on the subject also found that COVID-19 vaccination does not increase the risk of miscarriage or stillbirth[8,9].
Not only was COVID-19 not associated with a risk of pregnancy loss, it also did not increase the risk of other adverse pregnancy outcomes. In fact, studies from the US and Israel found that vaccinated and unvaccinated women had the same risk of outcomes such as preterm birth or young gestational age[10,11].
In summary, all of these studies have consistently shown that COVID-19 vaccines do not cause miscarriage or stillbirth.
Pharmacosurveillance databases such as VAERS alone cannot prove that a vaccine caused the adverse event
Using VAERS data showing an increase in miscarriages in 2021 and 2022 to imply that COVID-19 vaccines are dangerous is misleading and an abuse of the database. VAERS provides a way for the public and medical professionals to report adverse events that have occurred in people after vaccination. The system is jointly managed by the US Centers for Disease Control and Prevention (CDC) and the US Food and Drug Administration (FDA). It serves as a “national early warning system to identify potential safety issues with US-approved vaccines” that “can provide valuable information to the CDC and FDA that additional work and evaluation is needed to further assess potential safety concerns.”
However, the database alone cannot be used to indicate that a vaccine is dangerous, as Health Feedback explained in previous reviews. First, because anyone can submit a report to VAERS, the information in the report is not verified. VAERS clearly warns users who rely on the database of this caveat: “Some reports may contain information that is incomplete, inaccurate, random or unverifiable. Most reporting to VAERS is voluntary, meaning it is biased.”
Second, VAERS data alone cannot show whether an adverse event is the result of vaccination. In fact, the mere fact that Event A occurs before Event B does not mean that the first caused the second. Proposing otherwise is known as a post hoc ergo propter hoc fallacy. Further research on VAERS reporting is needed to determine if there is a causal relationship.
Finally, the number of adverse events such as death or miscarriage reported in VAERS is influenced by people’s propensity to submit such reports. Intense media attention to COVID-19 vaccines and their safety has likely led to greater public awareness, which plausibly has also led to more reports being filed, biostatistician Jeffrey Morris told FactCheck.org. Therefore, the greater number of reports being filed for the COVID-19 vaccines compared to previous vaccines is not necessarily indicative of a more dangerous vaccine.
