1. Department of Pediatrics Shinshu University School of Medicine MatsumotoJapan
2. Center for Perinatal, Pediatric, and Environmental Epidemiology Shinshu University School of Medicine MatsumotoJapan
3. Department of Pediatrics Nagano Red Cross Hospital NaganoJapan
4. Department of Neonatology and Developmental Medicine Shinshu University School of Medicine MatsumotoJapan
5. Nagano Children’s Hospital Azumino Japan