Discussion
The current analysis of the population-based Espoo Cohort Study aimed to
investigate the association between residential green vegetation during
pregnancy and early life and the risk of asthma, with a special interest
in trimester-specific and seasonal effects. Our study showed that
exposure to abundant greenness during pregnancy is associated with an
increased risk of asthma in children. Specifically, maternal exposure
during pregnancy to residential greenness during the spring season was
related to a significantly increased risk of asthma in the offspring.
Furthermore, the association was stronger when the mothers had such
exposure to greenness in their third trimester in comparison to when
exposure was in earlier trimesters.