1. Department of Obstetrics and GynecologyUniversity of Texas Medical Branch Galveston TX USA
2. The George Washington University Biostatistics Center Washington DC USA
3. Northwestern University Chicago IL USA
4. Ohio State University Columbus OH USA
5. MetroHealth Medical Center‐Case Western Reserve University Cleveland OH USA
6. The Eunice Kennedy Shriver National Institute of Child Health and Human Development Bethesda MD USA
7. University of Alabama at Birmingham Birmingham AL USA
8. Brown University Providence RI USA
9. Wayne State University Detroit MI USA
10. Columbia University New York NY USA
11. University of Texas Southwestern Medical Center Dallas TX USA
12. The University of Texas Health Science Center at Houston‐Children's Memorial Hermann Hospital Houston TX USA
13. University of Utah Health Sciences Center Salt Lake City UT USA
14. Oregon Health & Science University Portland OR USA
15. University of North Carolina at Chapel Hill Chapel Hill NC USA
16. University of Pittsburgh Pittsburgh PA USA
17. Medical University of South Carolina Charleston SC USA
18. University of Texas Medical Branch Galveston TX
19. Northwestern University Chicago IL
20. NorthShore University HealthSystem
21. The Ohio State University Columbus OH
22. St. Ann's
23. Case Western Reserve University‐MetroHealth Medical Center Cleveland OH
24. University of Alabama at Birmingham Birmingham AL
25. Brown University Providence RI
26. Wayne State University Detroit MI
27. RDMS
28. Columbia University New York NY
29. Drexel
30. St. Peter's
31. Christiana
32. University of Texas Southwestern Medical Center Dallas TX
33. The University of Texas Health Science Center at Houston‐Children's Memorial Hermann Hospital Houston TX
34. University of Utah Health Sciences Center Salt Lake City UT
35. McKay‐Dee
36. LDS Hospital
37. Intermountain Medical Center
38. UVRMC
39. Oregon Health & Science University Portland OR
40. Providence Sacred Heart Medical Center
41. Kaiser Permanente
42. University of North Carolina at Chapel Hill Chapel Hill NC
43. University of Pittsburgh Pittsburgh PA
44. The George Washington University Biostatistics Center
45. Eunice Kennedy Shriver National Institute of Child Health and Human Development Bethesda MD