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M. Casas, S. Cordier, and M. Vrijheid, Mark Nieuwenhuijsen, and Joelle Fevotte designed the study with the contribution and approval of all the other co-authors

G. Balcius and R. Gra?ulevi?ien?, MoBa: Merete Eggesbø, Karl-Christian Nordby

E. Patelarou, Maribel Casas and David Martínez harmonized the datasets and 37

X. Saúde, Admininstação Regional de Saúde do Norte

. Inma_granada, This study was funded by grants from Instituto de Salud Carlos III (Red INMA G03 Spanish Ministry of Health (FIS-07/0252, the EU Commission-00603 and CONTAMED FP7-ENV-212502), and Consejería de Salud de la Junta de Andalucía

. Inma_new, This study was funded by grants from UE (FP7-ENV-2011 cod 282957 and HEALTH.2010.2.4.5-1), Instituto de Salud Carlos III (Red INMA G03

. Moba, The Norwegian Mother and Child Cohort Study): The study is supported by