Stress During Pregnancy Increases Baby's Asthma Risk
Babies born to mothers who experienced stress during pregnancy have a higher risk of developing asthma later in life, according to new research from Brigham and Women’s Hospital and Harvard Medical Center, presented online in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine.
A previous study by researchers at Harvard in 2008 had similar findings.
Rosalind Wright, MD MPH, an associate physician at Brigham and Women’s Hospital, and colleagues recruited pregnant women in several cities, including Boston, Baltimore, New York, and St. Louis. The 557 families were mostly ethnic minorities, and 20% were living below the poverty level. At least one of the parents had a history of asthma or allergy.
Asthma is known to be more prevalent among ethnic minorities and those who live in disadvantaged communities, but the relationship is not always explained by environmental factors.
Each family answered questions about various stressors in their lives, at home (including domestic violence), financial situation, and instances of community violence. When the infant was born, cord blood was collected and researchers isolated immune cells which were analyzed for the production of various cytokines which would indicate the response of the infant’s immune system.
The researchers found patterns in the cytokines that were related to the level of stress by the mothers. The women that experienced higher stress levels had a greater risk of developing asthma and allergy when they got older, based on the immune system function at birth.
The role of stress in asthma development is not well understood. Animal studies have suggested that the mother’s stress during pregnancy can influence the immune system during fetal development. Dr. Wright says that prenatal stress may enhance the neonate’s response to inhaled antigens, such as dust mites.
The research, a prospective cohort study funded by the National Institute of Allergy and Infectious Diseases, will continue as the infants grow up to continue to follow the infants to evaluate the actual occurrence of asthma development.
Rosalind J. Wright, Cynthia M. Visness, Agustin Calatroni, Mitchell H. Grayson, Diane R. Gold, Megan T. Sandel, Aviva Lee-Parritz, Robert A. Wood, Meyer Kattan, Gordon R. Bloomberg, Melissa Burger, Alkis Togias, Frank R. Witter, Rhoda S. Sperling, Yoel Sadovsky, and James E. Gern. Prenatal Maternal Stress and Cord Blood Innate and Adaptive Cytokine Responses in an Inner-city Cohort. American Journal of Respiratory and Critical Care Medicine, 2010; DOI: 10.1164/rccm.200904-0637OC