Institution: | aDepartment of Obstetrics and Gynecology, University of Colorado School of Medicine, Anschutz Medical Campus, 12631 East 17th Avenue, Mail Stop B-198, Academic Office 1, Room 4010, Aurora, CO 80045, USA;bDepartment of Epidemiology, 505A Parran Hall, University of Pittsburgh, Pittsburgh, PA 15261, USA |