1. Department of Obstetrics and Gynecology, Duke University Medical Center , Durham, NC 27701, USA
2. Department of Population Health Sciences, Duke University Medical Center , Durham, NC 27701, USA
3. Department of Medicine, Harvard Medical School , Cambridge, MA 02115, USA
4. Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Duke University Medical Center , Durham, NC 27701, USA