1. Department of Ob/Gyn, Heersink School of Medicine, University of Alabama at Birmingham , Birmingham, AL 35233 , USA
2. Division of General Internal Medicine and Health Services Research, The David Geffen School of Medicine, UCLA , Los Angeles, CA 90024 , USA
3. Department of Ob/Gyn, The David Geffen School of Medicine, UCLA , Los Angeles, CA 90024 , USA
4. Department of Medicine, Heersink School of Medicine, University of Alabama at Birmingham , Birmingham, AL 35233 , USA
5. Department of Ob/Gyn and Medicine, Heersink School of Medicine, University of Alabama at Birmingham , Birmingham, AL 35233 , USA