1. Department of Obstetrics and Gynecology, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
2. Hospital Mater Dei, Belo Horizonte, Brazil
3. Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
4. Hospital Odilon Behrens, Belo Horizonte, Brazil