Foetal exposure to maternal stressful events increases the risk of having asthma and atopic diseases in childhood

Background: The natural history of asthma and atopic diseases begins in utero. Studies investigating the influence of foetal exposure to maternal stressful life events during pregnancy (SLEP) on asthma and atopic diseases are lacking. Aim: To test whether the children of mothers who had experienced SLEP are at an increased risk for asthma, atopic eczema and allergic rhinitis. Methods: The association between maternal SLEP (at least one among: divorce, mourning or loss of the job) and the occurrence of asthma and atopic diseases in childhood was studied in a population (n = 3854) of children, aged 314 yrs, living in Northern Italy. The parents filled in a standardized questionnaire about the childrens health and the events occurred to their mothers during pregnancy. Results: Three hundred and thirty-three (9%) of the mothers experienced SLEP. Their children had a statistically significantly higher lifetime prevalence of wheezing (31.6% vs. 23.1%), asthma (8.9% vs. 5.6%), allergic rhinitis (10.9% vs. 7.3%) and atopic eczema (29.7% vs. 21.1%) than those of mothers without SLEP. After adjusting for potential confounders, the foetal exposure to SLEP was positively associated with wheezing (OR: 1.41, 95% CI: 1.031.94), asthma (OR: 1.71, 95% CI: 1.022.89), allergic rhinitis (OR: 1.75, 95% CI: 1.082.84) and atopic eczema (OR: 1.53, 95% CI: 1.112.10). Conclusion: The children of mothers who had experienced SLEP were at a moderately increased risk of having wheezing, asthma, eczema and allergic rhinitis during their childhood. Maternal stress during pregnancy might enhance the expression of asthma and atopic phenotypes in children.