COVID-19 vaccine

Several types of vaccines are currently in development against COVID-19, among those in production there are:
(Drugbank.com online, CDC 2020/12/18 y 2020/12/13):
• Messenger ribonucleic acid vaccines (mRNA): BNT162b2, Tozinameran (Pfizer-BioNTech) and MRNA-1273 (Moderna & NIH). This type of vaccine uses portions of mRNA replicated from coronavirus n-19 to induce the synthesis and production of coronavirus n-19 surface proteins from muscle cells located at the site of injection that then act as triggers for the production of antibodies against the COVID-19 virus by the immune system.
• Viral vector-based vaccines: AZD1222 o ChAdOx1 nCoV-19 (Oxford Uni-AstraZeneca) and Gam-COVID-Vac (Gamaleya-Sputnik V). These vaccines use a non-pathogenic strain of human adenovirus that has been modified to contain genetic material that resembling a portion of coronavirus 2019-nCoV that can induce the immune system to react in a way similar to what was previously described with mRNA vaccines.

At the time this last update was completed, we did not find published data regarding the excretion of this substance through breast milk and of the impact that could have on lactation or the breastfeeding child. Currently breastfeeding women have been excluded from all clinical trials (Palacios 2020, Costantine 2020, CDC 2020/12/15, ABM 2020/12/14).

It is highly improbable that any of the components that are part of the vaccines produced against COVID-19 could be excreted through human breastmilk, and even in this could happen, they would all be digested in the gastrointestinal tract of the breastfeeding child (InfantRisk 2020/12/18).
It would seem reasonable to deduct that if the disease (COVID-19) is compatible with lactation then the vaccine developed against it would be even more so, since it does not carry the live virus within its components.

Neither of the types of vaccines currently in development against COVID-19 contain live viruses or preservatives within their components and therefore cannot provoke the disease or cause any alterations to the genetic material of their host (CDC 2020/12/18 y 2020/12/13).
Except for two live attenuated virus vaccines (small pox and yellow fever) that are known to rarely bring about negative effects on breastfeeding children, all vaccines are to be regarded as safe for use during lactation and therefore can be prescribed to breastfeeding women (CDC 2020/02/04).

Similar to what happens when vaccinating against other viruses, the use of a vaccine against COVID-19 would trigger the production of antibodies and the excretion through breastmilk of mainly the IgA type, which would likely help protect the breastfeeding child from COVID-19. (InfantRisk 2020/12/18, ABM 2020/12/14).

Breastfeeding women are not considered to be a high-risk group for COVID-19, specially since they tend to be young and usually healthy and therefore until now there are no specific reasons that would warrant the use of the vaccine in this group.
Several Health institutions, medical societies and also expert consensus have suggested that the vaccine should only be prescribed for breastfeeding women if they would also belong to a high-risk group such as healthcare workers or people afflicted by a chronic disease or condition known to be a risk factor (IHAN 2021, AELAMA 2021, NHS 2021, HIFN 2020, MS España 2020/12/30, ACOG 2020/12/13, CDC 2020/12/15 y 2020/12/13).

Vaccinating against COVID-19 should not be an impediment to begin lactation nor a cause for its interruption (ACOG 2020/12/13).

See below the information of this related product:

• Maternal Coronavirus 2019-nCoV infection (COVID-19) (Very Low Risk)