1. Epidemiology Branch, Division of Intramural Research, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
2. School of Public Health, University of Nevada, Reno, Nevada, USA
3. Division of Laboratory Sciences, National Center for Environmental Health, US Centers for Disease Control and Prevention, Atlanta, Georgia, USA
4. Department of Environmental Health Sciences, University of Michigan School of Public Health, University of Michigan, Ann Arbor, Michigan, USA
5. Division of Maternal-Fetal Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA