Vaccinated Nursing Moms Produce COVID-19 Antibodies In Breastmilk – Israeli Study

An Israeli study has found that vaccinating breastfeeding mothers promotes the production of important antibodies in their breastmilk, potentially contributing to the protection of their nursing babies.

The study was conducted jointly by Tel Aviv University and the Tel Aviv Sourasky Medical Center – Ichilov to discover whether the Pfizer/BioNtech COVID-19 vaccine was effective in producing antibodies in breastmilk, and to determine the qualities of these antibodies.

The initial findings were released this week in a pre-print. The article has not yet undergone peer review.

The research included 10 breastfeeding mothers in their 30s and took place during January and February 2021, soon after the vaccines became available in Israel. The women received two shots of the vaccine, 21 days apart, and the levels of antibodies in both their blood and breastmilk were tested at four points in time following vaccination, according to the study.

The researchers found that the women’s blood and breastmilk were well synchronized with one another, with regard to the rise of the levels of the specific antibodies generated by the vaccine. In both blood and breastmilk, the significant increase occurred 14 days after the first jab, and continued seven days after the second shot.

Moreover, they found that the antibodies in breastmilk hold the potential to neutralize the virus. Specifically, they can block the virus from binding with receptors on host cells and are important for preventing the disease.

In the study, the scientists wrote that “neutralizing capacity was observed in all samples.”

“The encouraging data show that vaccinating breastfeeding mothers promotes the production of important antibodies in their breastmilk, potentially protecting their nursing babies from the disease,” said Dr. Yariv Wine who led the research team at Tel Aviv University with PhD student Aya Kigel from the Shmunis School of Biomedicine and Cancer Research at the Faculty of Life Sciences.

The team at the Lis Maternity and Women’s Hospital at the Tel Aviv Sourasky Medical Center was led by Dr. Michal Rosenberg-Friedman and Professor Ariel Many.

For previous, unrelated studies on COVID-19, pregnancy, and lactation, see:

• Robust and Specific Secretory IgA Against SARS-CoV-2 Detected in Human Milk
• Characterization of SARS-CoV-2 RNA, Antibodies, and Neutralizing Capacity in Milk Produced by Women with COVID-19
• Early Identification of IgA Anti-SARSCoV-2 in Milk of Mother With COVID-19 Infection
• COVID-19 Vaccination in Pregnant and Lactating Women