Updated December 22, 2020
Recently we have had many consultations about the compatibility of the COVID-19 vaccine with breastfeeding. In some countries like the UK it has already been given to certain groups of people, such as health professionals or people who are at increased risk. If you have been recommended the vaccine because of your personal situation/condition and you are breastfeeding, is the vaccine compatible with breastfeeding?
On 21/12/2020 the European Medicines Agency (EMA) has published on the safety of the vaccine with mRNA technology marketed by the pharmaceutical companies Pfizer and Moderna for breastfeeding mothers: “It is unknown whether Comirnaty is excreted in human milk. If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before you receive this vaccine” (1). Even so, many international organisations point out that it could be safe.
There is no clear position on this issue due to the fact that research has not been carried out on breastfeeding mothers. But it is known that no viruses capable of causing the disease have been used in the manufacturing process of the vaccines and the components of the vaccine are, according to the manufacturers, safe. This is the case with other vaccines that are considered compatible with breastfeeding, such as vaccines against the flu, rabies or zika (2).
According to the Texas Infant Risk Center, it is very unlikely that the substances in these vaccines will reach the milk, and there is the possibility that the baby may obtain some immunity to COVID-19 (3).
The US Centers for Disease Control and Prevention (CDC) published on 12/12/2020 that although there are no data on the safety of COVID-19 vaccines in breastfeeding people or on the effects for the baby, vaccines of this type do not carry viruses capable of producing the disease and are not believed to be a risk to the baby. If a breastfeeding woman is part of a group that is recommended to receive the COVID-19 vaccine, such as health care workers, she may choose to be vaccinated (4).
On 14/12/2020, the American College of Obstetricians and Gynecologists published an article on its website recommending that breastfeeding women should be offered the COVID-19 vaccine if they are part of a risk group for which the vaccine is indicated, as the benefits of vaccination outweigh the possible side effects. This organisation points out that it is not necessary to avoid the start or interrupt breastfeeding in people who receive the COVID-19 vaccine (5).
The Academy of Breastfeeding Medicine (ABM) is in favour of vaccination against COVID-19 during breastfeeding, stating that vaccines during breastfeeding do not affect the safety for mother or baby (except for smallpox and yellow fever vaccines) (6).
On the same day, the UK Medicines & Healthcare products Regulatory Agency, pointed out in the Pfizer/BioNTech COVID-19 vaccine data sheet that it is not known whether the vaccine passes into breastmilk and therefore a risk to newborns cannot be excluded and that it is not recommended during lactation (7). This is, so far, the only official agency that has rejected the use of the vaccine in breastfeeding women.
On 20/12/2020, the website e-lactancia, which reviews the compatibility of diseases and medicines with breastfeeding, has rated the Covid-19 vaccine as “low risk for breastfeeding” (8), and therefore considers it quite safe, probably compatible and of low or unlikely risk. According to e-lactancia, it is highly unlikely that Covid-19 vaccine components will be passed into breast milk. On the contrary, it considers that antibodies generated by the vaccine could be passed as IgA, which would protect the infant from the disease, as is the case with vaccines against other viruses.
Furthermore, e-lactancia adds that “the position against vaccination of breastfeeding mothers taken by the UK National Health Service, the same as that of the manufacturers (NHS 2020/12/18), lacks scientific rigour as it does not take into account what is already known about vaccines and breastfeeding. It is hoped that they will change their position in future updates.”
One day later, on 22/12/2020, the Spanish Agency of the Medicine underlined that although there are no studies available on lactation, no risk is expected (9). It added that in the decision to vaccinate breastfeeding women, the benefits and risks should be evaluated individually by a health professional.
In many cases, medicines or vaccines are taken out of the reach of breastfeeding mothers due to a lack of data on their safety during breastfeeding. Research in the field of breastfeeding and the compatibility of different medicines is complicated, as clinical trials with breastfeeding mothers are usually not possible. Even so, there is experience with vaccines that have been on the market for years with a technology similar to that now used in the COVID-19 vaccine. It is essential that further research and common sense of health professionals does not lead to breastfeeding women being forced to decide between protection from COVID-19 or continuing with their breastfeeding journey.
(1) Committee for Medicines Products for Human Use. European Medicine Agency. Product Information as approved by the CHMP on 21 December 2020, pending endorsement by the European Commission. European Medicines Agency. Sciences Medicine Health. 21/12/2020. Available here: https://www.ema.europa.eu/en/documents/product-information/comirnaty-product-information-approved-chmp-21-december-2020-pending-endorsement-european-commission_en.pdf. 21/12/2020
(2) Centers for Disease Control and Prevention. COVID-19 (Coronavirus Disease). Understanding mRNA COVID-19 Vaccines. 18/12/2020. Available here: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines/mrna.html. 21/12/2020.
(3) Infant Risk. COVID-19 Vaccine in Pregnancy and Breastfeeding. Infant Risk Center at Texas Tech University Health Sciences Center. 18/12/2020. Available here: https://www.infantrisk.com/covid-19-vaccine-pregnancy-and-breastfeeding?fbclid=IwAR1ENvFsHmeDMRr138wJFZkbWFRIeLSfJ2ciuwrkQ3ZzdMALM-XqPcWGHes. 20/12/2020.
(4) Center for Disease Control and Prevention. Interim Clinical Considerations for Use of mRNA COVID-19 Vaccines Currently Authorized in the United States. Vaccines & Immunizations. 20/12/2020. Available here: https://www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html?CDC_AA_refVal=https://www.cdc.gov/vaccines/covid-19/info-by-product/pfizer/clinical-considerations.html. 21/20/2020.
(5) Riley, Laura; Beigi, Richard; Jamieson, Denise J. ; Hughes, Brenna L.; Swamy, Geeta; O’Neal Eckert, Linda; Gyamfi-Bannerman, Cynthia; Turrentine, Mark.. Vaccinating Pregnant and Lactating Patients Against COVID-19. ACOG. American College of Obstetricians and Gynecologists. 13/12/2020. Available here: https://www.acog.org/en/Clinical/Clinical%20Guidance/Practice%20Advisory/Articles/2020/12/Vaccinating%20Pregnant%20and%20Lactating%20Patients%20Against%20COVID%2019. 20/12/2020.
(6) Academy of Breastfeeding Medicine. ABM STATEMENT Considerations for COVID-19 Vaccination in Lactation. American Breastfeeding Medicine. 14/12/2020. Available here: https://www.bfmed.org/abm-statement-considerations-for-covid-19-vaccination-in-lactation. 19/12/2020.
(7) Medicine and Health Care products Regulatory Agency. Decision. Information for Healthcare Professionals on Pfizer/BioNTech COVID-19 vaccine. Medicine and Health Care products Regulatory Agency. 16/12/2020. Available here: https://www.gov.uk/government/publications/regulatory-approval-of-pfizer-biontech-vaccine-for-covid-19/information-for-healthcare-professionals-on-pfizerbiontech-covid-19-vaccine. 19/12/2020.
(8) e-lactancia.org. APILAM, Association for Promotion of and cultural and scientific Research into Breastfeeding. Vacuna contra la COVID-19. e-lactancia. 21/12/2020. Available here: http://e-lactancia.org/breastfeeding/covid-19-vaccine/product/. 21/12/2020.
(9) Agencia Española del Medicamento y Productos Sanitarios. Preguntas y respuestas sobre Comirnaty. Agencia Española del Medicamento y Productos Sanitarios. 21/12/2020. Disponible en: https://www.aemps.gob.es/la-aemps/ultima-informacion-de-la-aemps-acerca-del-covid%e2%80%9119/preguntas-y-respuestas-sobre-comirnaty/. 22/12/2020.