1. Doctoral School, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania
2. Faculty of Medicine, Carol Davila University of Medicineand Pharmacy, 020956 Bucharest, Romania
3. Department of Neonatology, Emergency University Hospital, 050098 Bucharest, Romania
4. Department of Obstetrics and Gynecology, Emergency University Hospital, 050098 Bucharest, Romania
5. Department of Neonatology, Marie Curie Children Hospital, 041451 Bucharest, Romania
6. Department of Neonatology, Filantropia Clinical Hospital, 011171 Bucharest, Romania