Yes, data show that after receiving mRNA COVID-19 vaccines, pregnant people can pass on their antibodies to the child. These antibodies have been found in umbilical cord blood, which means that the placenta has transferred protective immune cells from the vaccinated person to the infant. They have also been found in breastmilk.
This transfer of antibodies to infants helps strengthen their vulnerable immune system when they’re too young for vaccination. In both of these cases, during pregnancy and while breastfeeding, more data are needed to determine how much protection these antibodies may provide to the baby.
Added December 14, 2023