Vaccines are generally either inactivated vaccines made with antigens of the target organism or the organism’s RNA, or live-attenuated strains of the organism (1).

For more detailed information and references on specific medications, please refer to LactMed, e-lactancia, Infant Risk, or Mother to Baby.

Inactivated vaccines include influenza, hepatitis A, B, C, pneumococcal, polio, meningococcal, tetanus, diphtheria, pertussis, amongst others (1). There is no absolute indication to pump and dump with inactivated vaccines.

• COVID-19 vaccine: Very few side effects have been found among lactating mothers and their infants (2). There is no absolute indication to pump and dump with the COVID-19 vaccines. See the section on COVID-19 Vaccines & Medications.

There is no indication to pump and dump. Live attenuated vaccines include the measles, mumps and rubella (MMR) vaccine and the varicella vaccine. Live-attenuated vaccines are highly unlikely to infect the infant when given to the breastfeeding mother so there is no absolute indication to pump and dump with most live attenuated vaccines (1), although special considerations exist for the yellow fever and smallpox vaccines.

• Yellow fever vaccine: There are at least 2 case reports of probable transmission of yellow fever associated disease in infants whose breastfeeding mothers received the vaccine but the infants did not. The US Advisory Committee on Immunization Practices recommends that if a lactating parent must travel to a region endemic with yellow fever, and risk of disease in high, that the parent undergo vaccination (1).
• Smallpox vaccine: There are 2 forms of this vaccine and one is safe during lactation (3,4).
  • The JYNNEOS vaccine is safe, there is no absolute indication to pump or dump. This vaccine is live, but replication incompetent, so it is not expected to cause infant illness.
  • The ACAM2000 should not be used during lactation. This is a live virus vaccine that is able to replicate. It is contraindicated for infants under 1 year of age, and for immunocompromised patients.
• Monkeypox vaccine: The smallpox vaccines are used for monkeypox as well – see the section above. The JYNNEOS vaccine is safe, there is no absolute indication to pump or dump. This vaccine is live, but replication incompetent, so not expected to cause infant illness (3,4).