Study Finds Vaccination During Pregnancy Decreases Baby’s COVID-19 Risk

Data from a study published in February's CDC Morbidity and Mortality Weekly Report suggest that COVID-19 vaccination during pregnancy provides substantial protection for mother and baby.

This study offers the first real-world evidence that COVID-19 vaccination during pregnancy can provide protection and keep infants safe.

Compared to babies born to women who were not vaccinated during pregnancy, babies of mothers who received a two-dose mRNA vaccine during pregnancy were 61% less likely to be hospitalized with COVID-19 within the first 6 months of life.

While the mRNA vaccines were effective whenever expectant mothers were vaccinated, they provided more protection when given 21 weeks or later into the pregnancy, according to the CDC study.

Because pregnant people are at high risk for complications if infected with COVID-19, the CDC recommends COVID-19 vaccination for those who are pregnant to prevent severe illness and death. The CDC assures vaccination is safe and effective for both mother and baby.

The American College of Obstetricians and Gynecologists also recommend COVID-19 vaccine and booster shots for all eligible pregnant people.

Vaccine-generated antibodies appear to pass from mother to baby in utero and provide protection against severe illness and hospitalization, say the authors of this study.

“Today’s news is highly welcome, particularly in the backdrop of the recent increase in hospitalizations among very young children,” exclaimed Dr. Dana Meaney-Delman, chief of the CDC’s Infant Outcomes Monitoring Research and Prevention Branch, during a press briefing.

“Unfortunately, vaccination of infants younger than six months old is not currently on the horizon, highlighting why vaccination during pregnancy is so important,” she explained.

The study examined data from nearly 400 infants less than 6 months old who were hospitalized in 17 states from July 2021 to January 2022 — roughly half of these infants were hospitalized due to COVID-19, while the other half served as a control group.

In both groups, the median age was 2 months old, and around 20% of the babies had at least one underlying condition, while another 20% were born prematurely.

The CDC study found that, among the infants hospitalized with COVID-19, 84% were born to mothers who had not been vaccinated during pregnancy.

Additionally, the study suggests that the timing of vaccination during pregnancy matters. Babies born to mothers who were vaccinated at least 21 weeks into their pregnancies were 80% less likely to be hospitalized with COVID-19 than those of unvaccinated moms. This number decreased to 32% for babies born to mothers who were vaccinated in the first 20 weeks of pregnancy.

Although the CDC has not recommended vaccination at any specific time during pregnancy, becoming vaccinated later in pregnancy might lead to greater protection for the baby. Meaney-Delman explained that pregnant individuals are susceptible to severe illness and pregnancy complications if infected with COVID-19, so being protected as early as possible is vital for the mother's health.

Pregnant COVID-19 patients are roughly 40% more likely to develop serious complications or die than their uninfected peers, according to a JAMA study.

Although vaccination rates have risen, given the robust data supporting the safety and effectiveness of mRNA vaccines, data shows vaccination rates among pregnant people are less than the general United States population.

Data, gathered by the Kaiser Family Foundation as part of its COVID-19 Vaccine Monitor, showed that 18% of all adults believe at least one piece of medical misinformation about the COVID-19 vaccine and pregnancy. When zooming in on pregnant people alone, that number jumps to 29%, underscoring not just a need for better patient education about vaccines, but the overall threat of medical misinformation.

Since children under 5 are ineligible for vaccination against COVID-19, the CDC's report provides reassuring data for new and expecting parents.

Because the FDA expert committee has postponed the meeting to discuss expanding the authorization of Pfizer­–BioNTech's vaccine to children aged from 6 months to 4 years, babies and toddlers may not be eligible for vaccination until more clinical data can be collected. Meanwhile, getting vaccinated during pregnancy provides protection otherwise not available to children.