Right now, there is no data to help breastfeeding mothers decide whether or not to get vaccinated against COVID-19. Yet vaccination could protect not only them, but also their breastfed infants – thanks to antibodies in their breastmilk.

To find out, the University of California San Diego School of Medicine is launching an urgent study with a USD 200,000 donation from the Family Larsson-Rosenquist Foundation.

Scientists expect first results this spring. The data should provide critical answers and clear up uncertainties for mothers worldwide. The study will begin with vaccines from Pfizer-BioNTech and Moderna, then expand to include vaccines from other suppliers, ensuring there will be relevant data for women getting vaccinated in LMICs.

“We want this study to bring peace of mind to mothers in every single country,” says Dr. Katharina Lichtner, FLRF Managing Director. “No woman should be left behind.”

Tune in to an interview with Dr. Lars Bode, Professor of Pediatrics and Director of the Larsson-Rosenquist Foundation Mother-Milk-Infant Center of Research Excellence at UC San Diego, to learn more:

23 January 2021 - NBC 7, by Mari Payton: "One-of-a-Kind Study Could Be Life-Saving for Breastfeeding Women and Their Babies During COVID-19"

22 January 2021 - CBS 8, by Heather Hope: "UCSD study looks at impact vaccines have on breastfeeding mothers and their babies"

21 January 2021 - KUSI TV, by Ginger Jeffries: "San Diego Researchers Looking into Effects of Vaccine from Breast Milk"

You can also discover more about MOMI CORE here and keep current on related developments by subscribing to our newsletter.


University of California San Diego launches urgent study on COVID-19 vaccines and breastfeeding, with donation from Family Larsson-Rosenquist Foundation

San Diego, USA and Frauenfeld, Switzerland, 19 January 2021 – The University of California San Diego School of Medicine is investigating how COVID-19 vaccines may not only benefit breastfeeding mothers, but also their breastfed infants, thanks to a USD 200,000 donation from the Family Larsson-Rosenquist Foundation.

So far, breastfeeding women have not been included in any SARS-CoV-2 vaccine trials. The lack of data has led to some concerns about whether breastfeeding women should get vaccinated.

“Recommending that breastfeeding women forego either vaccination or breastfeeding will have tremendous global public health consequences, particularly in low- and middle-income countries,” says Dr. Lars Bode, Professor of Pediatrics and Director of the Larsson-Rosenquist Foundation Mother-Milk-Infant Center of Research Excellence (MOMI CORE) at UC San Diego. “In fact, we believe that vaccinating breastfeeding women will also benefit the breastfed infant.”

The study being conducted at MOMI CORE in collaboration with Mommy’s Milk Human Milk Research Biorepository led by Dr. Christina Chambers, also at UC San Diego, aims to investigate whether maternal antibodies generated in response to the vaccine are transferred through breastmilk and protect the breastfed infant from COVID-19.

Results from this study could inform guidance by global health organisations that would help women make informed decisions about receiving a COVID-19 vaccination while breastfeeding their children. 

“Women should not have to choose between vaccination and breastfeeding,” says Dr. Katharina Lichtner, Managing Director, FLRF. “By supporting this study, we hope to clarify public health recommendations and bring peace of mind to mothers.”

Sample collection from volunteers is underway. The study will run for approximately one year, with first data expected this spring for immediate publication.  

To ensure critical information is also directly relevant to women in LMICs, FLRF will consider further donations to investigate vaccines with delivery mechanisms expected for rollout in LMICs. FLRF is now working with investigators to determine next steps, and it will announce details as soon as they are confirmed.

“The topic of vaccination and breastfeeding is a worldwide concern,” says Göran Larsson, Chairman of the Board, FLRF. “Breastfeeding has lifelong benefits for children and mothers, so the decisions mothers must make today about vaccination and breastfeeding will affect generations of children to come.” 

In 2020, FLRF donated CHF 100,000 to the collaborative study by UC San Diego and the University of California Los Angeles that showed SARS-CoV-2 is not transmitted via breastmilk (Chambers et al. 2020 JAMA; Krogstad et al. 2021, in preparation). Their data contributed to changes in global World Health Organization recommendations on breastfeeding.

FLRF and UC San Diego have an established relationship of working together to advance research in breastfeeding and breastmilk, beginning when LRF MOMI CORE was founded in 2017. The partners believe that knowledge generated today will inform global health tomorrow, so the pursuit of new knowledge must be ongoing.

In fact, a method that will be critical to study COVID-19 vaccines and breastfeeding was developed as part of a 2020 MOMI Seeds pilot grant project (The Role of Early Food and Environmental Exposures through Breastmilk in the Development of Atopic Conditions in a Preterm Population). MOMI Seeds grants, born in 2018, fund early-stage, innovative multidisciplinary breastmilk research projects.


About the Larsson-Rosenquist Foundation Mother-Milk-Infant Center of Research Excellence at the University of California San Diego School of Medicine
The Larsson-Rosenquist Foundation Mother-Milk-Infant Center of Research Excellence (LRF MOMI CORE) at the University of California San Diego School of Medicine was established in 2017 to create an engine of discovery focused on understanding human milk by fostering collaborative investigation across research, education and clinical practice to improve the health and development of infants, mothers, and society as a whole.

About the Family Larsson-Rosenquist Foundation
The Family Larsson-Rosenquist Foundation was established in 2013, born from the vision of a world in which every child is granted an optimum start in life through the benefits of breastmilk. Based in Frauenfeld, Switzerland, it is one of the world’s only philanthropic foundations dedicated entirely to supporting and promoting breastfeeding and breastmilk.

Backed by sound science, its objective is to drive changes in practice that will increase rates of breastfeeding and improve the health of mothers and children worldwide. It furthers this objective by contributing to the long-term discovery, dissemination and deployment of evidence-based knowledge. Together with a global network of leading experts, it is creating publicly available, sustainable resources and educational tools that help healthcare providers, governments, communities and families overcome obstacles and achieve their breastfeeding goals.


Michelle Brubaker
Phone: +1 858-249-0456

Cassandra Petrakis Zwahlen
Phone: +41 41 510 05 15