1. Department of Obstetrics & Gynecology; Oregon Health & Science University; Portland Oregon USA
2. School of Public Health; Oregon Health & Science University/Portland State University; Portland Oregon USA
3. Department of Obstetrics, Gynecology, and Reproductive Sciences; University of Pittsburgh; Pittsburgh Pennsylvania USA
4. California Maternal Quality Care Collaborative (CMQCC); Stanford California USA
5. Sutter Medical Center; Sacramento Sacramento California USA
6. University of California, Irvine Medical Center; Orange California USA.