1. Department of Epidemiology, Cardiovascular Health Research Unit; University of Washington; Seattle MA
2. Department of Biostatistics; University of Washington; Seattle MA
3. Department of Environmental and Occupational Health Sciences; University of Washington; Seattle MA
4. Department of Medicine; University of Washington; Seattle MA
5. Department of Epidemiology; Harvard School of Public Health; Boston MA
6. Center for Perinatal Studies; Swedish Medical Center; Seattle MA