1. Consultorio Familiare, South Padua District, Azienda ULSS 6 Euganea, Veneto Region, National Health Service, 35042 Este, Italy
2. Prenatal Medicine, Azienda ULSS 6 Euganea, Veneto Region, National Health Service, 35131 Padova, Italy
3. National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford OX3 7LF, UK
4. School of Nursing and Midwifery, Queens University Belfast, Belfast BT9 7BL, UK
5. Maternità in Difficoltà®, 35138 Padova, Italy