During the pandemic, Dr. Anthony Fauci, the former top medical adviser to the White House, publicly reassured women that COVID-19 vaccines were safe for pregnant women, stressing that there were "no warning signs" to worry about.
But leaked messages recently revealed that he may have been secretly questioning this assessment, sparking a storm of controversy over the veracity of official recommendations and reigniting the debate about the safety of vaccines for pregnant women, especially after several women came forward with testimonies about having miscarriages after receiving the vaccination.
Privately over text, Fauci admitted concerns about COVID vaccine side effects “associated with miscarriage in the 1st trimester,” yet told the public there was nothing to worry about.
Television presenter Megyn McCain and billionaire investor Bill Ackman topped the list of prominent voices sharing personal stories of pregnancy loss. McCain said she suffered a miscarriage during the pandemic, while Ackman said his wife, Neri Oxman, lost seven babies. However, neither specified whether the miscarriages occurred immediately after vaccination. Other women also shared heartbreaking stories on social media about miscarriages occurring days after receiving the booster shot
The claim of an increased risk of miscarriage stems from a 2021 study, where critics argued that available data suggested a miscarriage rate of approximately 82% among women who received the vaccine during the first trimester. However, this figure was later found to be misleading, as the study's authors acknowledged a flaw in their method of calculating the miscarriage rate, and the Centers for Disease Control and Prevention (CDC) confirmed that the 82% figure was inaccurate.
To explain how this figure came about, the scientific detail reveals that the 82% conclusion did not stem from a standalone study, but rather from a selective reanalysis of data from the Centers for Disease Control and Prevention.
Scientists contacted nearly 4,000 pregnant women who had received the vaccine three months prior and found that 712 of them had healthy babies, while 104 had miscarriages and one had a stillbirth. The vast majority of the participants were still pregnant. The average miscarriage rate was 12.6%, which is within the normal range. However, critics decided to exclude women in their third trimester from the calculation, arguing that they were less likely to miscarry than those in earlier stages. This left 127 full-term pregnancies and 104 miscarriages, resulting in an 82% rate. This exclusion ignored more than 3,000 women who were in their first or second trimester and were still pregnant, making the figure completely detached from sound scientific analysis.
This calculation was widely criticized, with the Centers for Disease Control and Prevention (CDC) describing it as "inappropriate." Immunologist Vicki Malley also emphasized that the figure does not reflect the true miscarriage rate, but rather the impossibility of a woman transitioning from the first trimester to delivery in just three months.
Since then, scientific evidence has accumulated to refute these concerns. Additional research and separate studies have found that the COVID-19 vaccine is safe for pregnant women, and there is no evidence that it increases the risk of miscarriage. A large 2021 study from Minnesota involving 105,000 pregnant women found that the miscarriage rate among vaccinated women was 8.6% compared to 8% among unvaccinated women—a negligible difference that does not indicate any increased risk. Another Norwegian study analyzed data from 18,000 pregnant women and found that the miscarriage rate among vaccinated women was 5.1% compared to 5.5% among unvaccinated women, further confirming that there is no link between vaccination and miscarriage.
Experts explain that the natural miscarriage rate ranges between 10 and 20% of all pregnancies, with 80% of these occurring before the 12th week. Miscarriage can happen for many reasons, including problems with the developing fetus, hormonal imbalances, advanced maternal age, diabetes, obesity, or smoking. Since miscarriage is not uncommon, doctors point out that many cases mistakenly believed to be linked to the vaccine would have occurred regardless, and that the timing is what has led some to make an unfounded connection.
Research also confirms that the vaccine poses no other risks to the mother or fetus. There is no evidence that it increases the risk of premature birth, low birth weight, or birth defects. A 2022 study involving 40,000 pregnant women found no link between the vaccine and these complications. In fact, the benefits of vaccination outweigh the risks, especially since pregnant women with COVID-19 are three times more likely to be hospitalized and three times more likely to require advanced life support compared to non-pregnant women. Furthermore, vaccination helps protect newborns through the transfer of antibodies from mother to fetus.
Ultimately, scientists emphasize that there is no evidence that the COVID-19 vaccine affects future fertility, as the virus primarily affects the respiratory system, and there is no evidence of a direct impact on the reproductive organs. During the pandemic, Dr. Anthony Fauci, the former White House chief medical advisor, publicly reassured the public that COVID-19 vaccines were safe for pregnant women, stating that there were "no warning signs" indicating any risk.
