1. Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
2. Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul, Korea.
3. Statistics and Data Center, Samsung Medical Center, Seoul, Korea.
4. Heavy Metal Exposure Environmental Health Center, Dong-A University, Busan, Korea.
5. Department of Preventive Medicine, Dong-A University College of Medicine, Busan, Korea.
6. Department of Food and Nutrition, College of Human Ecology, Kyung Hee University, Seoul, Korea.
7. Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
8. Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
9. Department of Pediatrics, CHA Gangnam Medical Center, CHA University College of Medicine, Seoul, Korea.
10. Department of Obstetrics and Gynecology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
11. Department of Obstetrics and Gynecology, Integrative Medicine Center, Korea University Medical College, Seoul, Korea.
12. Department of Obstetrics and Gynecology, CHA Gangnam Medical Center, CHA University College of Medicine, Seoul, Korea.
13. Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Yonsei University Health System, Seoul, Korea.
14. Department of Pediatrics, Childhood Asthma Atopy Center, Environmental Health Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.