Misleading: Covid vaccine particles are present in breast milk.

By: Laura Vitelli
October 10 2022

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Misleading: Covid vaccine particles are present in breast milk.


The Verdict Misleading

Although new research has shown this to be true, this does not mean that the vaccine is unsafe.

Claim ID 22fb3ea0


A recent article in JM Pediatrics reports recent findings that show that COVID-19 vaccine mRNA can be detected in the breast milk of some lactating women who received the vaccination within six months after giving birth. Another recent study has shown that the vaccine can cause a temporary increase in menstrual cycle length in some women. 


Some social media users have interpreted these studies as a warning against vaccination or against breastfeeding after receiving the vaccination, while others are claiming that this validates claims about the vaccines' ability to cause harm. These findings were also recently referred to in an interview with author Naomi Wolf on GB News. In the interview, Wolf stated that several claims she made a year ago about the COVID-19 vaccine's negative consequences for female reproductive health had been proven true by recent studies.


In fact

These claims misrepresent the findings of the studies in question. While it is true that the findings contradict previous assertions about the vaccine's effects, this is to be expected as the COVID-19 vaccine is a relatively new treatment and was introduced under emergency conditions. As further research is carried out, more detailed information will likely emerge about the vaccine's interactions with the human body. 


The recent study by JM Pediatrics concerning the presence of breast milk is one such example. The study took samples of expressed breast milk from 11 breastfeeding mothers who had given birth within six months before the study. Samples were taken before and after participants received the COVID-19 vaccine to determine whether or not vaccine mRNA was present in the breast milk after the vaccine was administered. Researchers found trace amounts of vaccine mRNA in 7 samples from 5 participants at various times up to 45 hours post-vaccination. However, the study also found no vaccine mRNA was detected in prevaccination or postvaccination samples of expressed breast milk beyond 48 hours of collection.


The study affirms that it is safe for breastfeeding women to receive the COVID-19 vaccine but suggests that it may be advisable to wait for 48 hours after vaccination before resuming breastfeeding, as there is not yet any research on the safety and suitability of administering the COVID-19 vaccine to infants under six months of age. This is in line with guidelines given by various medical organizations. 

Some social media users have noted that this study demonstrates that the lipid nanoparticles in the COVID-19 vaccine can be transported to areas of the body far from the injection site. This contradicts previous research that indicated that the vaccines remain near the site of injection and local lymph nodes. Although this shows a need for further research, there is not yet any evidence that this is cause for alarm, nor is there evidence that the spike protein created by the mRNA vaccines causes damage to the human body. 


Another recent study in BMJ Medicine has shown that the vaccine can cause a temporary increase in menstrual cycle length and heavier bleeding in some women. An article in Science.org notes that this is not unheard of among vaccine side effects and offers the explanation that "Just like infections and fevers, which are known to affect periods, the immune system's response to vaccination may alter sex hormone patterns or the cells that build up and break down the uterine lining, both of which are interlinked with immunology."


In the aforementioned interview with GB News, Naomi Wolf and interviewer Mark Steyn suggested that these studies prove that the COVID-19 vaccine does indeed cause fertility problems among both men and women. The studies referenced do not support this claim. Studies have shown that the COVID-19 virus impacts male testosterone levels and sexual function. There is not yet any scientific evidence that the COVID-19 vaccine has similar effects. 



Although recent studies have advanced our understanding of the COVID-19 vaccine's effects on the human body, these findings are limited and do not support the anti-vaccine claims in which they are referenced. There is no evidence that the vaccine does damage the human reproductive system. These claims have therefore been found to be misleading.

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