1. University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA.
2. Department of Obstetrics and Gynecology, Hospital Materno-Infantil, La Paz, Bolivia.
3. Kardiozentrum, La Paz, Bolivia.
4. Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA.
5. Department of Medicine, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA.