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COVID-19 vaccine safe for pregnant, nursing mothers: experts

Hinshaw hosts town hall on COVID-19 vaccine and whether or not it is safe during pregnancy and beyond
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The protection antibodies that lactating or breastfeeding women get from the mRNA vaccine are present in the breast milk, and those protection antibodies make it to the baby, said Dr. Eliana Castillo, an associate professor from the Cumming School of Medicine at the University of Calgary, at a telephone town hall on Oct. 27, 2021.

Albertans got the opportunity to ask doctors questions about COVID-19 and maternal health issues last week.

On Oct. 27 chief medical officer of health Dr. Deena Hinshaw held a telephone town hall about vaccines, pregnancy, and fertility.

The town hall was an hour-and-a-half in length. Dr. Eliana Castillo and Dr. Verena Kuret answered questions submitted online or over the phone. Castillo, an associate professor, and Kuret, a clinical assistant professor, are both from the Cumming School of Medicine at the University of Calgary.

The first question asked during the town hall was whether the vaccine is safe for breastfed babies to ingest and whether there is evidence to support a breastfeeding mother getting the vaccine.

Castillo responded by clarifying when the mRNA vaccine, along with all other intramuscular vaccines, are injected into the arm, the vaccine cells and the vaccine components stay in the arm muscles and the lymph nodes. In the lymph nodes the vaccine, "does what it is supposed to do."

The vaccine encourages our bodies to make protection antibodies against the virus, and then those protection antibodies go into the bloodstream.

“The vaccine itself does not get into the blood, but the protection that your body gets from the vaccine. Those are the ones that go through your bloodstream,” Castillo explained.

Someone who is breastfeeding, she continued, would have those protection antibodies travel from the bloodstream into the breast milk where the protection would go to the baby.

“We have scientific evidence that has demonstrated the protection antibodies that lactating or breastfeeding women get from the vaccine are present in the breast milk. We have the evidence to show that those protection antibodies make it to baby.

“We do not have any evidence and we would not expect that the vaccine itself or any of its components would make it into breast milk,” she said.

In a question about how long the antibody protection lasts for babies, through either breast milk or placental blood, Castillo said they don’t yet know how long the COVID-19 maternal antibodies last.

They do know, through studies from vaccines for influenza, the protection the baby gets from the mother being vaccinated during pregnancy lasts up to six months.

They also have evidence from the whooping cough vaccine that shows the antibodies a baby gets from its mother lasts up to eight or nine months. But, Castillo said, they don’t have the data for COVID-19 maternal antibodies.

Kuret added there is a difference between the antibodies from a naturally-occurring COVID infection and the antibodies our bodies make after receiving the vaccine.

“We now have several studies that have shown that our bodies actually make better antibodies in terms of the quantity and quality after vaccination,” Kuret said. “So, we encourage individuals who are pregnant to still receive the COVID vaccine, even if they've had an infection, because those antibodies are superior to those with just a natural infection.”

Helen, from Calgary, had concerns about alleged reports of babies dying in Alberta hospitals and spike proteins spreading across the body and crossing the blood-brain barrier. She wondered why the COVID vaccine is being mandated.

Kuret said she is part of a large provincial working group that meets regularly, sometimes weekly. At the beginning of the pandemic, one of the first things they did was develop provincial guidance for care providers to make sure they were looking out for exactly what Helen described.

“So, to make sure we're investigating any unexpected or unexplained outcomes, such as a baby dying, I can tell you that from being a part of that committee for the last 18 or 20 months, that that's not the experience that I have heard from the information that's been collected,” said Kuret.

What there has been, she continued, are rare infections of COVID in newborns.

As for the spike protein portion of the question, Castillo reiterated the vaccine and its components do not travel from mother to baby, only the antibody protections.

“There is no evidence that the COVID-19 — the spike protein — that our bodies make after the vaccine stays in our system for a long time,” Castillo explained.

The spike protein that our bodies make in response to the COVID vaccine is out of our bodies within a few weeks, like any other protein.

“The mRNA, per se, that comes with the vaccine is out of our system through normal processes within seven days,” she said.

However, mothers who have a COVID-19 infection can have their babies prematurely, Castillo said.

Of kids, Hinshaw pointed out, children under one year have the highest risk of severe outcomes, and the best way to protect them is to minimize their chances of being exposed.

Hinshaw also pointed out, with regard to a question about vaccine safety in pregnancy, COVID-19 infection carries risk for pregnant women, and the Delta variant has been a game-changer.

Castillo said during the fourth wave, Alberta has seen 20 pregnant patients in the intensive care unit.

Kuret interjected to put that number in context.

“When we look at the information that Dr. Castillo and I have been tracking prior to that, in all of the waves combined — one, two, and three — the total has been 16. We have already, in a short space of one wave with the Delta variant, had more ICU admissions than in the entire previous pandemic,” Kuret said.

According to Alberta data, pre-term birth is really high for those women who have been hospitalized with the virus.

 “[Preterm birth is high] for women in the third trimester that have not been vaccinated, that have a severe infection, and we're delivering [babies] by emergency C-sections prematurely in an attempt to help save [mothers'] lives, and hopefully create some room for their lungs to be able to expand and breathe,” Kuret said.

In response to a final question about Moderna vaccine safety and breastfed babies, Castillo said it’s particularly important to go back to risk negotiation.

Getting COVID-19 while pregnant or breastfeeding and putting babies under one at risk for COVID-19 infection can have serious consequences versus the theoretical concerns that may arise in social media about the components of the Moderna vaccine, said Castillo.

“The story of [a] baby getting sick with COVID or the story of a pregnant mom in [the] intensive-care unit — that story may sound as spooky [as] the story of an adverse event from the vaccine itself affecting the pregnant mother or that baby.

“All I can tell you is that even though the two stories may sound equally scary to you, all of us are here tonight to share with you that COVID-19 is a reality. We understand that it has to be very difficult to read all the very fearful messages that are out there in social media. And yet, in situations like this, we have to do a risk negotiation and we try our best to differentiate facts from the story.”

The full recording can be found at

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