About the Authors

Astanand Jugessur

Contributed equally to this work with: Astanand Jugessur, Min Shi

Affiliations Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway, Craniofacial Research, Musculoskeletal Disorders, Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Australia

Min Shi

Contributed equally to this work with: Astanand Jugessur, Min Shi

Affiliation Biostatistics Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, Durham, North Carolina, United States of America

Håkon Kristian Gjessing

Affiliations Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway, Department of Public Health and Primary Health Care, University of Bergen, Bergen, Norway

Rolv Terje Lie

Affiliations Department of Public Health and Primary Health Care, University of Bergen, Bergen, Norway, Medical Birth Registry of Norway, Norwegian Institute of Public Health, Bergen, Norway

Allen James Wilcox

Affiliation Epidemiology Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, North Carolina, United States of America

Clarice Ring Weinberg

Affiliation Biostatistics Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, Durham, North Carolina, United States of America

Kaare Christensen

Affiliation Department of Epidemiology, University of Southern Denmark, Odense, Denmark

Abee Lowman Boyles

Affiliation Epidemiology Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, North Carolina, United States of America

Sandra Daack-Hirsch

Affiliation College of Nursing, University of Iowa, Iowa City, Iowa, United States of America

Truc Trung Nguyen

Affiliation Medical Birth Registry of Norway, Norwegian Institute of Public Health, Bergen, Norway

Lene Christiansen

Affiliation Department of Epidemiology, University of Southern Denmark, Odense, Denmark

Andrew Carl Lidral

Affiliation Departments of Pediatrics, Epidemiology and Biological Sciences, University of Iowa, Iowa City, Iowa, United States of America

Jeffrey Clark Murray

jeff-murray@uiowa.edu

Affiliations Department of Epidemiology, University of Southern Denmark, Odense, Denmark, Departments of Pediatrics, Epidemiology and Biological Sciences, University of Iowa, Iowa City, Iowa, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: AJ MS RTL AW CRW KC JCM. Performed the experiments: AJ MS SDH LC ACL. Analyzed the data: AJ MS HG RTL AW CRW. Contributed reagents/materials/analysis tools: AJ MS HG RTL AW CRW KC ALB SDH TTN LC ACL JCM. Wrote the paper: AJ MS HG RTL AW CRW ALB JCM.