1Department of Environmental Exposure and Epidemiology, Domain of Infection Control and Environmental Health, Norwegian Institute of Public Health, P.O. Box 4404Nydalen, NO-0403 Oslo, Norway
2Department of Obstetrics and Gynecology, Sahlgrenska University Hospital, Gothenburg, Sweden
3Unit for Nutrition Research, Landspitali University Hospital and University of Iceland, Reykjavik, Iceland
4Department of Genetics and Bioinformatics, Domain of Health Data and Digitalisation, Norwegian Institute of Public Health, Oslo, Norway
5Office of the Director-General, Norwegian Institute of Public Health, Oslo, Norway
6Department of Health and Social Sciences, Bergen University College, Bergen, Norway
7Department of Obstetrics and Gynecology, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
© The Author(s). 2017
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