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Geoffrey Donovan, Yvonne Michael, David Butry, Amy Sullivan, John Chase
Abstract
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.
Donovan, G.
, Michael, Y.
, Butry, D.
, Sullivan, A.
and Chase, J.
(2011),
Urban trees and the risk of poor birth outcomes, Health & Place, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=907256
(Accessed October 11, 2025)