1. Department of Obstetrics and Gynecology; School of Medicine; Fukushima Medical University; Fukushima Japan
2. Fukushima Regional Center for the Japan Environmental and Children's Study; Fukushima Japan
3. Department of Pediatrics; School of Medicine; Fukushima Medical University; Fukushima Japan
4. Department of Public Health; School of Medicine; Fukushima Medical University; Fukushima Japan