1. Department of Obstetrics and Gynecology, St. Marianna University School of Medicine, Kanagawa, Japan.
2. National Center for Child Health and Development, Children's Cancer Center, Tokyo, Japan.
3. Department of Pediatrics, Mie University Graduate School of Medicine, Tsu, Japan.
4. Department of Pediatrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
5. Department of Pediatrics, Hokkaido University, Sapporo, Japan.
6. Department of Obstetrics and Gynecology, Mie University, Tsu, Japan.
7. Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
8. Division of Hematology/Oncology, Kanagawa Children's Medical Center, Yokohama, Japan.
9. International Center for Reproductive Medicine, Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan.
10. Department of Pediatrics, St. Marianna University School of Medicine, Kanagawa, Japan.
11. Department of Obstetrics and Gynecology, Michigan State University, East Lansing, Michigan, USA.