1. Boston University School of Medicine/Boston Medical Center, Boston, Massachusetts, USA.
2. University of Pittsburgh/Magee-Women's Hospital, Pittsburgh, Pennsylvania, USA.
3. Division of Cancer Prevention and Control, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
4. Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, California, USA.
5. Division of Cancer Epidemiology and Genetics and Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland, USA.
6. Department of Obstetrics/Gynecology, Brigham and Women's Hospital, Boston, Massachusetts, USA.