COVID-19 SCIENCE UPDATE

Study refutes anti-vaxxers' pregnancy, breast milk claims

Unfounded claims by anti-vaccine activists that COVID-19 shots from Pfizer/BioNTech and Moderna will damage the placenta and contaminate breast milk have been refuted by new data.

The vaccines deliver synthetic messenger RNA (mRNA), which instructs the body to make proteins that in turn induce antibodies to attack the coronavirus.

Anti-vaxxers claim, with no evidence, that mRNA also induces antibodies that attack a protein called syncytin-1, which is important for the developing placenta during pregnancy.

They also claim mRNA from the vaccines ends up in breast milk. When researchers studied blood samples from 15 women who received at least one dose of the Pfizer/BioNTech vaccine - including two pregnant women and five who were breastfeeding - they saw coronavirus antibodies but no antibodies against syncytin-1.

None of the breastfeeding women had vaccine mRNA in their milk, according to a report posted Tuesday on medRxiv ahead of peer review.

"This small study tells us that it is unlikely that COVID-19 mRNA vaccination will cause complications in pregnancy or fertility through cross-reacting antibodies against syncytin-1, or for breastfed infants through breast milk," the authors said. -- Reuters