1. Department of Health Policy and Management, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania, USA
2. Magee-Womens Hospital, Pittsburgh, Pennsylvania, USA
3. Children's Hospital of Pittsburgh, Pennsylvania, USA
4. Magee-Womens Research Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
5. Departments of Obstetrics, Gynecology and Reproductive Sciences and Internal Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA