1. Department of Hematology, Hospital de Carabineros de Chile, Simon Bolivar 2200, Nuñoa, 7770199 Santiago, Chile
2. Faculty of Medicine, University Mayor, Renato Sanchez 4369, Las Condes, 7550224 Santiago, Chile
3. Feto-Maternity Unit, Hospital de Carabineros de Chile, Simon Bolivar 2200, Nuñoa, 7770199 Santiago, Chile