Pregnant women who eat peanuts may put infants at increased risk for peanut allergy, study finds

The data are reported in the November 1 issue of the Journal of Allergy and Clinical Immunology.

Led by Scott H. Sicherer, MD, Professor of Pediatrics, Jaffe Food Allergy Institute at Mount Sinai School of Medicine, researchers at five U.S. study sites evaluated 503 infants aged three to 15 months with likely milk or egg allergies or with significant eczema and positive allergy tests to milk or egg, which are factors associated with an increased risk of peanut allergy. The study infants had no previous diagnosis of peanut allergy. A total of 140 infants had strong sensitivity to peanut based on blood tests, and consumption of peanut during pregnancy was a significant predictor of this test result.

"Researchers in recent years have been uncertain about the role of peanut consumption during pregnancy on the risk of peanut allergy in infants," said Dr. Sicherer. "While our study does not definitively indicate that pregnant women should not eat peanut products during pregnancy, it highlights the need for further research in order make recommendations about dietary restrictions."

In 2000, the American Academy of Pediatrics recommended that women whose infants were at increased risk of allergies based upon family history consider avoiding peanut products while pregnant and breast feeding. However, the recommendation was withdrawn in 2008 due to limited scientific evidence to support it. The Consortium of Food Allergy Research (CoFAR), which was just awarded a renewed $29.9 million grant from the National Institutes of Health, is conducting this ongoing, observational study to help better understand the risk factors behind a child's developing peanut allergy, as well as allergies to milk and egg. The Consortium is also studying novel treatments for food allergies.

The authors caution that the study has limitations, including the reliance on the self-reporting of dietary habits among pregnant women. Importantly, the study has thus far only shown an increased risk for positive allergy test results to peanut.

Despite its limitations, the study has identified a potential risk factor that, if verified, could present an opportunity for risk reduction. The authors conclude that controlled, interventional studies should be conducted to explore these findings further.

"Peanut allergy is serious, usually persistent, potentially fatal, and appears to be increasing in prevalence," said Dr. Sicherer. "Our study is an important step toward identifying preventive measures that, if verified, may help reduce the impact of peanut allergy."