1. a Department of Gynaecology and Obstetrics, S. Giovanni di Dio Hospital , University of Cagliari , Cagliari , CA , Italy
2. b Department of Therapeutic Research and Medicines Evaluation , Istituto Superiore di Sanità , Rome , Italy
3. c Department of Internal Medicine , University of Cagliari , Cagliari , Italy
4. d Department of Infectious Diseases , S.S. Trinità Hospital, Cagliari , Cagliari , CA , Italy
5. e Neonatal Intensive Care Unit , University of Cagliari , Cagliari , CA , Italy