Affiliation: | 1. Department of Obstetrics, Gynecology & Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA;2. Department of Epidemiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA;3. Department of Pediatrics and Nemours Children's Health System, Thomas Jefferson University, Philadelphia, Pennsylvania, USA;4. Department of General Internal Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA |