A new study found that babies with probable milk or egg allergy were significantly more likely to be allergic to peanuts if their mothers ate them during their pregnancy, compared to similar infants whose mothers had not ingested peanuts during pregnancy. The study, published in the Journal of Allergy and Clinical Immunology was carried out by scientists from Mount Sinai School of Medicine, New York and some other US research centers and universities.

Peanut allergies can be severe and may last throughout the patient’s lifetime. In some cases an allergic reaction to peanuts may result in death. In 1998-2000 the American Academy of Pediatrics (AAP) and the Committee on Toxicology, UK recommended that mothers at risk of allergic disease refrain from ingesting peanuts while pregnant and breastfeeding. The authors explain that the advice from both sides of the Atlantic was based on very tenuous evidence. In fact, several experts have asked whether the recommendations should be reviewed. Consequently, the AAP no longer issues such advice.

Dr. Scott H. Sicherer and team studied 512 babies aged from 3 to 15 months who had had signs and symptoms of egg and/or milk allergy, eczema and a positive milk or egg allergy test result – but none of them had ever had a previous diagnosis of peanut allergy.

The researchers discovered that a mother’s consumption of peanuts during pregnancy was linked to stronger positive peanut allergy test results in their offspring – in other words, the babies had a greater risk of having a peanut allergy.

They also found that male, non-Caucasian babies had a higher risk of developing a peanut allergy.

They added that their findings add more evidence to support the advice regarding avoiding peanuts during pregnancy in order to reduce allergy risk in offspring. However, they fall short of saying their study findings should alter official recommendations.

Scott Sicherer said:

There have only been a handful of studies on this topic with some showing risks and others showing no risk of maternal ingestion of peanut. While our study underscores the need to keep an open mind on this topic, there remains more work to be done before any definitive recommendations can be made.

The authors say they plan to continue monitoring the babies to determine whether their positive peanut allergy test results eventually lead to the development of a peanut allergy. They add that further studies are required to back up their findings.

The authors concluded in the Journal of Allergy and Clinical Immunology:

In this cohort of infants with likely milk or egg allergy, maternal ingestion of peanut during pregnancy was strongly associated with a high level of peanut sensitization.

“Maternal consumption of peanut during pregnancy is associated with peanut sensitization in atopic infants”
Scott H. Sicherer, MD., Robert A. Wood, MD, Donald Stablein, PhD, Robert Lindblad, MD, Andrew H. Liu, MD, Stacie M. Jones, MD, David M. Fleischer, MD, Donald Y.M. Leung, MD, PhD, Hugh A. Sampson, MD
The Journal of Allergy and Clinical Immunology

Written by Christian Nordqvist