1. Department of Obstetrics and Gynaecology, Diakonische Dienste Hannover, Hannover
2. German Center for Growth, Development, and Health Encouragement during Childhood and Youth, Berlin
3. Jerusalem Hospital, Hamburg
4. Section of Perinatal Medicine, Department of Obstetrics and Gynaecology, Technical University of Munich, Munich
5. Department of Occupational, Social and Environmental Medicine, University Medical Center Göttingen, Göttingen