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Urban trees and the risk of poor birth outcomes



Geoffrey Donovan, Yvonne Michael, David Butry, Amy Sullivan, John Chase


This paper investigated whether greater tree-canopy cover is associated with reduced risk of poor birth outcomes in Portland, Oregon. Residential addresses were geocoded and linked to classified-aerial imagery to calculate percentage tree canopy in 50, 100, and 200m buffers around each home in our sample (n=5,696). Detailed data on maternal characteristics and additional neighborhood characteristics were obtained from birth certificates and tax records. We found that a 10% increase in tree-canopy cover within 50 m of a house reduced the number of small for gestational age births by 1.42 per 1,000 births (95% CI: 0.11-2.72). Results suggest the natural environment may affect pregnancy outcomes and should be evaluated in future research.
Health & Place


reproductive health, small for gestational age, preterm birth, urban trees


Donovan, G. , Michael, Y. , Butry, D. , Sullivan, A. and Chase, J. (2011), Urban trees and the risk of poor birth outcomes, Health & Place, [online], (Accessed June 20, 2024)


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Created December 31, 2010, Updated October 14, 2021