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This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Cumulative Effect Over Lag 0 to 2 Days from Exposure to Aeroallergens on the Risk of Delivery Among Preterm, Early- and Full-term Pregnancies, Pooled Across Six cities in Ontario, Canada, April–October, 2004–2011