1. Department of Epidemiology and Cancer Control, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 735, Memphis, TN 38105-2794,
USA
2. Department of Biostatistics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 768, Memphis, TN 38105-2794, USA
3. Current address: Biostatistics & Epidemiology Research Design Core, Center for Clinical and Translational Sciences, Department of Internal Medicine, Medical School, The University of Texas Health Science Center at Houston, UT Professional Building, Room 1100.10, 6410 Fannin Street, Houston 77030, USA
4. Division of Endocrinology, Department of Pediatric Medicine, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 737, Memphis, TN 38105-2794, USA
5. Fertility Associates of Memphis, 80 Humphreys Center Drive, # 307, Memphis, TN 38120-2363, USA
6. Department of Obstetrics and Gynecology, Vanderbilt University Medical School, 1161 21st Avenue South, R-1214 MCN, Nashville, TN 37232-2521, USA
7. Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065-6007, USA
8. Department of Oncology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 260, Memphis, TN 38105-2794, USA
9. Department of Radiation Oncology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Mail Stop 210, Memphis, TN 38105-2794, USA
10. Current address: Department of Radiation Oncology, The University of Texas Southwestern Medical Center 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
11. Department of Pediatrics, The University of Tennessee Health Sciences Center, 50 North Dunlap, Room 461R, Memphis, TN 38103-2800, USA