Infants are 61% less likely to be hospitalized with COVID-19 during their first six months of life when their mother had been vaccinated with an mRNA primary vaccine series during pregnancy, according to a study conducted in pediatric hospitals across the country.* Scientists had previously suspected that COVID-19 antibodies from mothers vaccinated during pregnancy would be passed to the baby across the placenta and protect the baby, but this is the first real-world evidence to support it. 

“This is huge,” said Dr. Barbra Fisher, M.D., Ph.D., maternal-fetal medicine specialist and surgeon at Northwest Perinatal Center in Portland. “A mother can get vaccinated to protect their baby, so you are getting vaccinated both for yourself and your baby.” 
 
Being vaccinated against COVID-19 can also help ensure a smooth pregnancy. If a pregnant person contracts COVID-19 and ends up hospitalized or on a ventilator, they may need to have the baby prematurely. There is also growing evidence, Fisher says, that having COVID-19 while pregnant increases the risk of still births and other pregnancy complications.  

When a pregnant person is vaccinated against COVID-19 during pregnancy, they develop antibodies against the virus and pass them on to the fetus through the placenta. Without those antibodies, newborns are also at risk for COVID-19-associated complications, including respiratory failure and other life-threatening complications. 

“There is less chances of complications during pregnancy, including pre-term birth, and we are passing antibodies across the placenta, so your baby will be healthier and have less chance of being infected during infancy,” Fisher said.  

Every pregnant patient Fisher has treated in hospital for COVID-19-related complications has been unvaccinated. “They have 100 percent been unvaccinated. I have not seen hospitalized, sick, pregnant, vaccinated people,” Fisher said.  

Some people have expressed concerns that the vaccines may cause infertility, but “there are no data to support this,” Fisher said. Fisher recommends listening to the guiding organizations** who all “unequivocally” recommend that people who are pregnant, trying to get pregnant now or might become pregnant in the future be vaccinated against COVID-19.  

The best period of pregnancy to be vaccinated in order to pass on the most antibodies to protect infants is not currently known, according to the Centers for Disease Control and Prevention (CDC). Pregnant people should get vaccinated as soon as possible and not wait until, for example, the third trimester, because the benefit of avoiding a COVID-19 infection outweighs any potential benefit of waiting, according to Fisher.   

*The study included data on 379 infants at 20 pediatric hospitals in 17 states between July and January, including 176 who had COVID-19.   

**These include the American College of Obstetricians and Gynecologists, Society for Maternal Fetal Medicine and the CDC.