1. Neonatal Intensive Care Unit with Neonatology, “G.F. Ingrassia” Hospital Unit, ASP 6, 90131 Palermo, Italy
2. Neonatology and Neonatal Intensive Care Unit, University Hospital Policlinic “Paolo Giaccone”, 90127 Palermo, Italy
3. Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties, University of Palermo, 90127 Palermo, Italy