1. German Center for Growth, Development and Health Encouragement during Childhood and Youth, Berlin, Germany
2. Section of Perinatal Medicine, Department of Obstetrics,Technical University of Munich, Germany
3. Department of Neonatology, Klinikum Südstadt, Rostock, Germany
4. Rostock, Germany
5. Department of Occupational, Social and Environmental Medicine, University Medical Center Göttingen, Germany