1. Department of Neonatology Perinatal Medical Center, Kagoshima City Hospital Kagoshima Japan
2. Department of Obstetrics and Gynecology Perinatal Medical Center, Kagoshima City Hospital Kagoshima Japan
3. Department of Neonatology Perinatal Medical Center, Imakiire General Hospital Kagoshima Japan
4. Department of Neonatology Perinatal Medical Center, Nagasaki Harbor Medical Center Nagasaki Japan