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What We Know About Vaccination, Breastfeeding, and Antibodies
An OB-GYN reviews the latest coronavirus research for lactating people

Many new moms and lactating people are searching for definitive answers about the Covid-19 vaccine and breastfeeding. Considering more than 3.7 million individuals give birth in the United States per year, clear evidence-based guidelines are needed as soon as possible.
Nearly 110 million doses have been administered in the United States. All adults are on schedule to be vaccinated by the end of May, but cities including Dallas and Minneapolis are seeing a surge in cases linked to dangerous Covid-19 variants. Lactating people need fast, reliable answers.
Experts agree that lactating individuals are candidates for vaccination. The American College of Obgyn unequivocally states that Covid-19 vaccines should be offered to those who are breastfeeding.
New evidence shows the vaccine benefits might be even better than we thought. Early data indicates vaccinated individuals may pass protective antibodies through breast milk. Vaccinating someone who plans to breastfeed may result in a “two-for-one special.”
A new preprint report titled “SARS-CoV-2 antibodies detected in human breast milk post-vaccination” is the first study to verify that moms pass protective antibodies through breast milk after vaccination. Most scientists anticipated breast milk would contain Covid-19 antibodies based on past vaccine experience. Antibodies are present in breast milk within five to seven days of other viral vaccinations such as Tdap and influenza.
Scientists have shown already that moms pass protective antibodies to their baby after Covid-19 infection. Previous research also demonstrated that these mothers produce antibodies and secrete them into their breast milk. An unanswered scientific question is “Do Covid-19 vaccinated individuals also secrete protective antibodies into breast milk?”
The small study evaluated breast milk samples from women after they had been vaccinated. Researchers tested the milk samples for SARS-CoV-2 specific IgG and IgA antibodies until 14 days after the mothers received their second dose of the Pfizer or Moderna vaccines.