Researchers find no signs of Pfizer, Moderna COVID-19 vaccines in breast milk in new study

In a study, researchers detected no evidence of Pfizer or Moderna COVID-19 vaccinations in human breast milk, implying that the mRNA preventives are safe during lactation. The study, which was published in the journal JAMA Pediatrics, provides the first direct evidence of vaccine safety while breastfeeding, which may allay fears among people who have refused vaccination or stopped breastfeeding because they are concerned that vaccination would change human milk.

No sign of COVID vaccines in breast milk

The breast milk of seven women who had received the Pfizer and Moderna mRNA vaccines was examined by researchers at the University of California, San Francisco (USCF), and no sign of the preventives was identified. Vaccines containing mRNA have been shown in the past to prevent the virus that causes COVID-19 from spreading. The World Health Organization (WHO) recommends that persons who are breastfeeding get vaccinated, according to the study.

There is little chance of vaccination nanoparticles or mRNA entering breast tissue or being passed to milk, according to the Academy of Breastfeeding Medicine, which might possibly impair newborn immunity.

Study corresponding author Stephanie L Gaw, an assistant professor at UCSF, stated, "The results strengthen current recommendations that the mRNA vaccines are safe in lactation, and that lactating individuals who receive the COVID vaccine should not stop breastfeeding."

Study lead author Yarden Golan, a postdoctoral fellow at UCSF, said, "We didn't detect the vaccine-associated mRNA in any of the milk samples tested."

No traces of Pfizer, Moderna in breast milk

The study, which took place between December 2020 and February 2021, provides experimental evidence for the safety of using mRNA-based vaccinations during lactation. The moms in the study were on average 37.8 years old, with children ranging in age from one month to three years old. Milk samples were taken before and after vaccination at various periods up to 48 hours later. 

Researchers discovered no measurable quantities of vaccination mRNA in any component of the milk in any of the samples. The researchers acknowledged that the study was restricted by the small sample size and that more clinical data from bigger populations was needed to better quantify the vaccinations' effect on lactation outcomes.

(With inputs from PTI)

Picture Credit: AP/PTI