1. Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center, Boston, Massachusetts
2. Department of Obstetrics and Gynecology, University of Colorado, Aurora, Colorado
3. Department of Obstetrics and Gynecology, Stanford University, Stanford, California
4. Department of Obstetrics and Gynecology, Santa Clara Valley Medical Center, San Jose, California
5. Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan