1. Department of Obstetrics and Gynecology, Memorial Care Center for Women at Miller Children’s Hospital Long Beach, Long Beach, CA, USA;
2. Department of Obstetrics and Gynecology, University of California, Irvine, Orange, CA, USA;
3. Cedars-Sinai Medical Center, Los Angeles, CA, USA;
4. Charles Drew University of Medicine and Science, Center for Health Services Research, Los Angeles, CA, USA;
5. Oakland University, William Beaumont School of Medicine, Rochester, MI, USA