Vitamin D status during pregnancy and wheezing and asthma during childhood

Background: Maternal vitamin D can have a protective role on child’s respiratory health, but the results from prospective studies are still inconsistent. We examined whether maternal circulating vitamin D levels during pregnancy are associated with wheezing and asthma during childhood in a Spanish birth cohort. Methods: Maternal circulating 25(OH)D3 levels were measured during the first trimester of pregnancy. Information on active wheezing (wheezing episodes plus medication), wheezing patterns (early, late-onset, and persistent wheeze), and physician-diagnosed asthma ever was obtained from parental questionnaires administered from 1 to 7 years in new cohorts(N=1964) and from 1 to 9 years i…