The peak season for RSV is now underway and runs through January. 

The RSV vaccine for pregnant women helps to protect the baby, even before birth.

“The way the pregnancy vaccine works is the vaccine causes the mom to make antibodies, and those antibodies cross the placenta, and then the baby is born with those antibodies ready to protect them against the virus,” Dr. Lauren Theilen with the University of Utah said.

Theilen says the best time for moms-to-be to get the vaccine is during their third trimester — between 32 and 36 weeks of pregnancy. The most common risks are soreness at the injection site, fatigue, muscle pain and nausea.

“We have to consider what the harms of not being vaccinated are,” Theilen said.

RSV symptoms can cause trouble breathing, coughing, poor feeding, lethargy, irritability. It can turn into pneumonia and can cause asthma during childhood. Dr. Theilen believes the vaccine is a crucial step in protecting newborns.

There's RSV vaccine approved by the FDA does not carry the risk of premature births. Another FDA-approved vaccine recommended for pregnant mothers protects their baby from whooping cough.

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