1. Division of Maternal-Fetal Medicine; Department of Obstetrics & Gynecology; Duke University Medical Center; Durham NC USA
2. Division of Hematology; Department of Medicine; Duke University, Medical Center; Durham NC USA
3. Department of Thrombosis and Hemostasis; Leiden University Medical Center; Leiden The Netherlands
4. Department of Oncology and Hematology-Oncology; Hematology and Transfusion Medicine; L. Sacco University Hospital; University of Milan; Milan Italy