1. Department of Health Policy and Management, University of Pittsburgh School of Public Health, Pittsburgh, Pennsylvania
2. Friends Research Institute, Baltimore, Maryland
3. Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco
4. Department of Obstetrics, Gynecology & Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
5. Magee-Womens Research Institute, Pittsburgh, Pennsylvania