1. Department of Obstetrics and Gynecology, Allegheny Health Network, Pittsburgh, Pennsylvania.
2. Biostatistics/Epidemiology/Research Design (BERD) Core, Center for Clinical and Translational Sciences, The University of Texas Health Science Center at Houston, Houston, Texas.
3. Asher Center for Research and Treatment of Depressive Disorders, Departments of Psychiatry and Behavioral Sciences and Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
4. Department of Obstetrics and Gynecology, Allegheny Health Network, Temple University School of Medicine, Pittsburgh, Pennsylvania.