Risk of childhood asthma and allergic rhinitis in relation to pregnancy complications

Background: Events occurring during Fetal life may affect the development o f the immune and respiratory systems and increase the risk of asthma and al lergic diseases. Objectives: We sought to elaborate the relations between the occurrence of pregnancy complications and other pregnancy-related conditions and the risk of bronchial obstruction during the first 2 years of life and the occurren ce of asthma and allergic rhinitis by the age of 4 years. Pregnancy complic ations were considered both as predictors of the health outcomes and as pos sible effects caused by other prenatal factors. Methods: A population-based, l-year, cohort study was carried out involving 2531 children horn in Oslo, Norway. We collected information on maternally related (hyperemesis, hypertension, and preeclampsia) and uterus-related c omplications in pregnancy (antepartum hemorrhage, preterm contractions, ins ufficient placenta, and restricted growth of the uterus) and the child's he alth and environmental exposures at birth and at 6, 12, 18, and 24 months a nd 4 years of age. The outcomes of interest were bronchial obstruction duri ng the first 2 years and asthma and allergic rhinitis at the age of 4 years . Results: In a logistic regression analysis adjusting for potential confound ers, uterus-related, but not other pregnancy-related, complications increas ed the risk of bronchial obstruction (odds ratio [OR], 2.1; 95% confidence interval [CI], 1,3-3.4), asthma (OR, 3.0; 95% CI, 1.8-5.4), and allergic rh initis (OR, 2.9; 95% CI, 1.6-5.2). These relations were similar in children of atopic and nonatopic parents. Conclusions: Uterus-related complications in pregnancy increase the risk of having asthma and allergic rhinitis in childhood.