New research has discovered that the COVID-19 vaccine is not only safe for breastfeeding mothers, but it’s possible to pass antibodies to infants via breast milk.

The study was conducted by researchers at Wroclaw Medical University, located in Wroclaw, Poland. The researchers wanted to look at the immune system response lactating mothers have to the COVID-19 vaccination, and furthermore, how this impacts breastfeeding. The results were recently published in the journal Vaccine.

Over the course of the study, the researchers analyzed breastmilk samples from 32 women who were breastfeeding and chose to vaccinate. The breastmilk samples were “collected on days 8 ± 1, 22 ± 2, 29 ± 3, and 43 ± 4 after the first dose of the vaccine,” the study explains. The samples were then analyzed for the presence of IgA and IgG antibodies. The increased presence of these antibodies is caused by a spike in glycoprotein, which is a result of the coronavirus vaccine.

In conclusion, the researchers found higher levels of the IgA and IgG antibodies in the breastmilk of lactating mothers who had received the vaccine. The highest concentration of the antibodies was observed on day 29, though these levels started to decrease by day 43. The researchers determined that the immune system response to the coronavirus vaccine was strongest a week after receiving the second dose.

Perhaps even more ground-breaking, however, is the fact that the higher levels of antibodies present in the breastmilk of vaccinated mothers suggest they may be able to pass COVID-19 antibodies through their children by lactating.

The researchers hope that their findings will encourage more breastfeeding women to get vaccinated. As of now, the rates of pregnant and breastfeeding women opting to get the vaccine are very low in comparison to the rest of the population. Earlier this month, the Center for Disease Control and Prevention (CDC) released a report stating that only 16% of pregnant women in the United States had received their first dose, while only 11% had received a second shot.

The CDC is currently recommending pregnant and breastfeeding women to get the vaccine, especially due to the increased risk a coronavirus infection has on expecting and postpartum women as well as their offspring. Vaccine trials are currently underway in order to better understand the efficacy and safety of the vaccine during pregnancy and lactation. For more information and to make an informed decision for yourself, we encourage you to speak to your healthcare provider.