1. Department of ObstetricsCharité – University Medicine Berlin Berlin Germany
2. Institute of Quality Assurance Hesse Eschborn Germany
3. INSERM U1153Obstetrical, Perinatal and Pediatric Epidemiology Research Team (EPOPé) Paris France
4. Children′s HospitalPhilipps University Marburg Marburg Germany
5. Department of ObstetricsHvidovre University Hospital Hvidovre Denmark
6. Department of ObstetricsUniversity HospitalPhilipps University Marburg Germany