A study from Denmark has been looking into the effects of taking fish oil supplements during pregnancy and have found women who took them in the last trimester significant;y reduce their child’s risk of developing asthma.

In the study, 700 pregnant women were put into two groups – one taking a dose of 2.4 grams of fish oil supplements and the others receiving a placebo. Among the children whose mothers took the fish oil supplement 16.9 percent developed asthma by the time they were three years old. While 23.7 percent of the children whose mothers took the placebo developed asthma – while the 7 percent may not seem significant, it actually translates to a 31 percent risk reduction.

“I would say that the finding that the effect was there was maybe not the surprise, because there have been indications,” says the study’s lead researcher, Dr. Hans Bisgaard, of the University of Copenhagen. “But the magnitude was very surprising to us.”

Asthma affects around 330 million people worldwide and researchers are eager to find a prevention as it can lead to dangerous breathing problems and chronic wheezing.

Despite the findings, researchers aren’t rushing to tell women to start taking fish oil capsules as more research needs to be done in order to find out the full effects. Fish oil is thought to reduce inflammation in the body and inflammation in the airways and lungs play a huge part in the trigger to asthma symptoms so the study suggestions are plausible according to experts.

But not all women would benefit from a larger dose of fish oil and those with low levels of EPA and DHA in the blood seem to gain the most from having a higher intake. Researchers are looking into a blood test to see which women would be better off taking the supplements and what dosage would be safe and recommended.

Details of the study were published in the New England Journal of Medicine.