1. Clínica Corachán, Barcelona, Spain;
2. Obstetrics and Gynecology, University of Granada, Granada, Spain;
3. Complejo Hospitalario de Jaen, Jaen, Spain;
4. Centre Meeic, Sitges, Spain;
5. Obstetrics & Gynecologic, University of Asturias, Oviedo, Spain;
6. Instituto Palacios, Madrid, Spain