1 Louisiana State University Health Sciences Center, School of Public Health, New Orleans, LA.
2 Magee-Womens Research Institute, Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA.
3 Magee-Womens Research Institute, Departments of Obstetrics, Gynecology and Reproductive Sciences and of Epidemiology and Clinical and Translational Research, University of Pittsburgh, PA.