This proposal is part of LongITools (B3289) and LifeCycle projects.

There is inconsistent evidence of an association between prenatal exposure to air pollution and adiposity in childhood. Some studies suggest positive associations, possibly with stronger magnitude in boys, some find no association, and others find inverse associations between prenatal air pollution and adiposity in childhood. Most studies have been relatively small (<3,500 participants) and assess adiposity at a single time point.

The potential mechanisms linking air pollution to adiposity are still uncertain. Maternal exposure to air pollution may affect fetal growth, and intrauterine growth restriction will influence later-life adiposity. Inflammation is another hypothesised mechanism of the association between prenatal air pollution and offspring adiposity, and this might also be part of the fetal growth pathway.

Using data from three birth cohorts (ALSPAC, BiB and Generation R), this project will assess the association of different measures of air pollution (PM10, PM2.5, NO2 and NO) during pregnancy with fetal growth, trajectories of adiposity in childhood, and maternal and offspring inflammation. We will also explore possible sensitive windows by assessing trimester-specific associations, and whether associations differ by sex. If associations of air pollution with fetal growth, inflammation and childhood adiposity are evident, we will explore and quantify possible mediation by fetal growth and inflammation in the association between prenatal air pollution and childhood adiposity.