Pregnant women vaccinated against Covid-19 could pass along protection to their babies, according to a study in Israel.
According to research in February, antibodies were detected in all 20 women administered both doses of the Pfizer-BioNTech vaccine during their third trimester of pregnancy and, through placental transfer, in their newborn babies.
"Our findings highlight that vaccination of pregnant women may provide maternal and neonatal protection from Sars-CoV-2 infection," the study said.
The findings by researchers from Jerusalem's Hadassah University Medical Centre were posted this month on medRxiv – an online distribution service for unpublished research manuscripts that have not been peer-reviewed – and reported by Israeli media on Tuesday.
The authors said the small size of the study meant further research was necessary to gauge the effect of vaccination at different stages of pregnancy, and the safety and efficacy of the different vaccines now available.
One of the researchers, Dana Wolf, told The Jerusalem Post the group would now start looking at how long the antibodies triggered by the vaccinations would last in the babies.
Pfizer and BioNTech said last month they had started a 4,000-volunteer international study to evaluate the safety and effectiveness of their Covid-19 vaccine in healthy pregnant women.
The trial will also assess whether vaccinated pregnant women transfer protective antibodies to their babies.
A separate US study posted last week and awaiting peer review, found that the antibodies induced in pregnant women from mRNA Covid-19 vaccines, such as the Pfizer/BioNTech and Moderna shots, were transferred to the babies through the placenta or breast milk.