1. Division of Hematology; National Center for Child Health and Development; Tokyo
2. Department of Pediatrics; Nara Medical University; Kashihara
3. Department of Perinatology; Nara Medical University; Kashihara
4. Department of Pediatrics; St. Marianna University School of Medicine, Yokohama City Seibu Hospital; Yokohama
5. Department of Obstetrics and Gynecology; Faculty of Medicine, University of Miyazaki; Miyazaki; Japan
6. Department of Obstetrics and Gynecology; Graduate School of Medical Sciences; Kyushu University; Fukuoka
7. Department of Clinical Chemistry and Laboratory Medicine; Kyushu University Hospital; Fukuoka
8. Department of Pediatrics; Kyushu University; Fukuoka