Objective
The objective of this study was to examine the relationship between maternal pre-pregnancy obesity and a diagnosis of asthma in offspring at age 3 years.

Methods
A population-based sample of children born in large U.S. cities in 1998-2000 was followed since birth (N=1971). The main outcome measure was whether the mother reported at 3 years that the child had ever been diagnosed with asthma. Multilevel logistic regression models were used to estimate the association between maternal pre-pregnancy obesity and child asthma diagnosis, as well as the extent to which that association can be explained by sociodemographic, medical, obstetric, and behavioral factors associated with both conditions.

Results
Children with obese mothers had 52% higher odds of having an asthma diagnosis by age 3 (OR = 1.52; 95% CI: 1.18 - 1.93). Sociodemographic, medical, obstetric, and behavioral factors explained some, but not all, of the association.

Conclusions
Maternal pre-pregnancy obesity is associated with diagnosis of asthma in offspring at age 3 years. The results from this study are preliminary and need to be replicated and further explored, but are suggestive of a complex intergenerational linkage between obesity and asthma.