Shortly after the corona vaccination, doctors detected traces of the mRNA preparation in breast milk in breastfeeding mothers – but both the researchers themselves and German experts continue to advise breastfeeding women to be immunized. In a small study, a team led by neonatologist Nazeeh Hanna from NYU Langone Hospital in New York analyzed milk samples from eleven women who had previously received the mRNA preparations from either Moderna or Biontech/Pfizer.
Using a very sensitive method, the team examined a total of 131 milk samples from the women, which were taken up to five days after the vaccination. The researchers found traces of the vaccines in a total of seven samples from five participants. None of the milk samples that tested positive for mRNA traces had been taken more than 45 hours after the vaccination.
The researchers speculate that nanoparticles containing the mRNA might reach the mammary glands via the bloodstream or the lymphatic system. The study did not examine whether the mRNA was still active, i.e. could theoretically lead to the formation of proteins. When asked, the German Society for Gynecology and Obstetrics (DGGG) emphasized that mRNA “is degraded in the stomach after oral intake, i.e. decomposed” and does not reach the bloodstream of the newborn.
The doctors around Hanna do not derive safety concerns from the evidence. Breastfeeding is safe even after an mRNA vaccination against Covid-19, they write in the journal “JAMA Pediatrics”. However, they advise caution in children up to the age of six months in the first 48 hours after vaccination until further study data on safety are available. Possible effects of vaccine mRNA on newborns have not been sufficiently studied.
The DGGG points out that the vaccination not only protects the mother from a severe course of Covid-19, but also reduces the risk of a Sars-CoV-2 infection in the child. “Based on these considerations, it does not seem sensible to limit the recommendation for vaccination of breastfeeding mothers,” emphasizes the specialist society.
