• Posted September 7, 2022

Taking 2 Supplements in Pregnancy Could Lower Baby's Odds for Croup

Many new parents have been jarred awake in the dead of night when they hear their baby let out that telltale barky cough that signals a bout of croup.

Until now, nothing was thought to stave off the disease in babies who are prone to it, but a new study has discovered that when women took high doses of fish oil and vitamin D supplements during pregnancy, their babies had around a 40% lower risk of developing croup.

Croup is a viral chest infection that mainly strikes kids under the age of 3. Symptoms include a barking seal-like cough, a hoarse voice, and a high-pitched, squeaky noise while breathing. Croup is usually mild, but some children will need more intensive treatment.

"There is currently no vaccine against the pathogen that causes this disease," explained study author Nicklas Brustad. He's a clinician and postdoctoral researcher working on the Copenhagen Prospective Studies on Asthma in Childhood at Copenhagen University Hospital in Denmark. "Therefore, other preventive strategies are needed, and measures initiated during pregnancy might be important since croup occurs in babies and young children."

This is where mega-doses of fish oil and vitamin D supplements during pregnancy could come in, he added.

Researchers aren't sure what it is about vitamin D and fish oil that protects against croup, but they have a theory. "It can stimulate the immune system to help babies and young children clear infections more effectively," Brustad noted.

For the study, 736 pregnant women were divided into four groups: high-dose vitamin D supplement (2,800 units daily) and fish oil, high-dose vitamin D and olive oil, standard-dose vitamin D (400 units daily) and fish oil, and standard-dose vitamin D and olive oil.

According to the U.S. National Institutes of Health, the current recommended intake of daily vitamin D for pregnant women is 600 units. However, the NIH notes that higher daily intakes -- up to 4,000 units daily -- remain safe for adults under 70. It's always a good idea to inform your physician of any changes in supplement use, as well.

Women in the study took the supplements every day beginning in the 24th week of their pregnancy and continued until one week after their babies were born. Kids were followed until their third birthday, to see if they developed croup. There were 97 cases of croup during the study period.

Children whose moms took fish oil had an 11% risk of croup, compared to 17% among kids whose mothers took olive oil, the study showed. Children whose mothers took high-dose vitamin D had an 11% risk of croup, compared to an 18% risk seen in those whose mothers took the standard-dose vitamin D.

It may be time to start recommending this regimen to pregnant women, Brustad said.

"We always want more studies confirming the results to change guidelines, but the supplements are considered relatively safe and cheap, so this could be a potential low-cost strategy against one of the most common respiratory diseases in childhood," Brustad said.

The findings were recently presented at the European Respiratory Society annual meeting, in Barcelona. Findings presented at medical meetings should be considered preliminary until published in a peer-reviewed journal.

Dr. James Antoon, an assistant professor of pediatrics at Monroe Carell Jr. Children's Hospital at Vanderbilt in Nashville, Tenn., routinely treats kids with croup.

"Croup is extremely common," Antoon said. "It is caused by inflammation in the throat when the airway starts to close."

Don't immediately hit the panic button when you hear the barky cough, he said. "Consider seeking medical care when symptoms are appearing when the child is at rest or he or she appears to be struggling to breathe," Antoon suggested.

Some kids can be safely treated at home, but others may need more aggressive treatment.

"An in-hospital breathing treatment takes away the inflammation in the short term and then we give oral steroids that are longer-acting to prevent inflammation from re-accumulating," Antoon said.

The only way to prevent croup is to prevent viral illness, he added. This means regular hand washing, covering your mouth when you cough and staying home when you're sick -- many of the things that were enforced during the early phase of the pandemic. They work, he said.

"During the early part of the pandemic, we saw a very remarkable decrease in cases of croup in children," Antoon noted. "It was unprecedented and very impressive."

More information

The American Academy of Pediatrics has more on treating croup in kids.

SOURCES: Nicklas Brustad, PhD, clinician, postdoctoral researcher, Copenhagen Prospective Studies on Asthma in Childhood, Copenhagen University Hospital, Denmark; James Antoon, MD, PhD, MPH, assistant professor, pediatrics, division of hospital medicine, Monroe Carell Jr. Children's Hospital at Vanderbilt, Nashville, Tenn.; European Respiratory Society annual meeting, Barcelona, Sept. 4-6, 2022