1. Department of OB/GYN, Divisions of Maternal-Fetal Medicine and Reproductive Genetics; University of Pennsylvania; Philadelphia PA USA
2. Department of OB/GYN, Division of Maternal Fetal Medicine; University of Washington; Seattle WA USA
3. Department of Pediatric General, Thoracic and Fetal Surgery, Center for Fetal Diagnosis and Treatment; The Children's Hospital of Philadelphia; Philadelphia PA USA