LEXINGTON, Ky. (FOX 56) — Researchers at the University of Kentucky are learning more about the effectiveness of the vaccines for COVID-19.

For decades, doctors have been advising pregnant women to get vaccinated for various illnesses as a means to transfer antibodies from mom to baby to protect the newborn during the first six months of its life when it’s too young to receive certain vaccinations.

Their latest study from March 2021 to June 2022, in partnership with the Oregon Health & Science University, looked specifically at pregnant mothers to see if the same applies to COVID-19.

Studies show pregnant women are at a higher risk of getting severely sick from COVID-19 and have a higher risk for preterm birth.

Researchers tracked 120 women through their pregnancy, delivery, and postpartum. Each participant received two rounds of vaccinations and a booster shot.

The team monitored antibody response in blood samples and breast milk.

Researchers found that vaccine antibodies do transfer from mother to fetus in utero, offering protection to both mom and baby during and after pregnancy. With that, there was a greater number of antibodies transferred through the placenta during pregnancy than through breast milk afterward.

Roughly 90% of the women who partook in the study received the Pfizer vaccine. This was primarily due to the availability of vaccines.

But experts said any vaccine is better than no vaccine.

“It’s really important to get those one, two and then booster, because what we show within the study is the levels of antibodies, both in the maternal circulation, which then know of course was reflected in the cord blood when we looked at it, but also in the breast milk dramatically increased with the booster,” said Dr. Illhem Messaoudi from UK’s Microbiology, Immunology, and Molecular Genetics department. “It doesn’t do you any good to get the first two and then stop.”

The study also tested the difference between getting vaccinated early in a women’s pregnancy versus later on and saw little to no difference.

Dr. Messaoudi said it is best to proactive.

“I know that some of the women I talked to you at the beginning of the pandemic were saying that they were going to wait till they got close to delivery so they could maximize the amount of antibodies. It’s really, really important to get vaccinated as soon as you can because if you wait, and you get COVID, and you end up in the ICU, that’s not going to help anybody,” Messaoudi explained.

Messaoudi also noted the study saw little difference between women who were in their first pregnancy, second, or third.


The findings come as COVID-19 cases continue to climb.

The Lexington-Fayette County Health Department saw 380 new COVID cases in the second week of January, 25 more than the week prior.

Researchers said they’ll continue to monitor study participants to learn more about the boosters’ effectiveness against the new omicron variant as well as if a woman gets pregnant for a second time after being vaccinated.

To learn more about the study, you can find it here.