Mom's Stress in Pregnancy May Up Baby's Asthma and Allergy Risk

A pregnant woman's anxiety may raise her baby's risk of allergies and asthma.

ByABC News
May 18, 2008, 5:04 PM

May 19 -- SUNDAY, May 18 (HealthDay News) -- If an expectant mother is exposed to high levels of stress, her baby may be more likely to develop asthma or allergies later in life, new research suggests.

Babies born to mothers experiencing high levels of stress had more IgE in their blood at birth than did babies born to less-stressed moms. IgE is an antibody involved in allergic and asthmatic reactions.

"Moms who had elevated levels of stress had children who seemed to be more reactive to allergens, even when exposed to low levels of allergens," said study co-author Dr. Rosalind Wright, an assistant professor of medicine at Brigham and Women's Hospital and Harvard Medical School in Boston.

Wright's colleague, and another author of the study, Junenette Peters, said that stress may make women more susceptible to allergens because it "may make the cells more permeable" so that even low levels of exposure trigger a reaction. And, women whose immune systems are altered by stress may, in turn, pass down that trait to their infants.

Peters, a postdoctoral research fellow at Harvard Medical School, was to present the findings Sunday at the American Thoracic Society's 2008 International Conference, in Toronto.

The study, which was funded by a grant from the U.S. National Heart, Lung, and Blood Institute, included 315 expectant mothers and their infants. All of the mothers lived in an urban environment.

Mothers filled out a questionnaire designed to assess their levels of stress in many different domains. Financial issues, home issues, community safety, relationship problems and medical issues were the most frequently reported negative events experienced by the mothers.

Dust mite exposure was also assessed using samples obtained from the pregnant women's bedrooms. When the babies were born, a sample of cord blood was taken.

After controlling the data to compensate for maternal age, race, smoking, education, history of allergy and asthma, the child's gender and the season of birth, the researchers found that the number of negative domains -- stressors -- reported was associated with an increased risk of elevated IgE in the cord blood.