1. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina
2. Duke School of Medicine, Duke University, Durham, North Carolina
3. Duke University Medical Center Library and Archives, Duke University School of Medicine, Durham, North Carolina
4. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Indiana University, Indianapolis, Indiana
5. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Wake Forest School of Medicine Atrium Health, Charlotte, North Carolina
6. Division of Population and Community Health, Department of Obstetrics and Gynecology, Duke University, Durham, North Carolina