1. Social Science Research Institute and Department of Biobehavioral Health, The Pennsylvania State University, University Park, Pennsylvania, USA.
2. RTI International, Research Triangle Park, North Carolina, USA.
3. Department of Biostatistics, Harvard University, Boston, Massachusetts, USA.
4. Barbra Streisand Women's Heart Center, Cedars-Sinai Smidt Heart Institute, Los Angeles, California, USA.
5. Department of Obstetrics and Gynecology, The Ohio State University, Columbus, Ohio, USA.
6. Department of Cardiology and Preventive Medicine, Northwestern University, Chicago, Illinois, USA.
7. National Heart, Lung, and Blood Institute, Bethesda, Maryland, USA.
8. Department of Obstetrics and Gynecology, Indiana University, Indianapolis, Indiana, USA.
9. Department of Obstetrics and Gynecology, Case Western Reserve University/MetroHealth, Cleveland, Ohio, USA.
10. Department of Obstetrics and Gynecology, Eastern Virginia Medical School, Norfolk, Virginia, USA.