1 Department of Biostatistics and Epidemiology, Environmental and Occupational Health Sciences Institute, Rutgers School of Public Health, Piscataway, New Jersey; Department of Obstetrics and Gynecology, University of Rochester School of Medicine and Dentistry, Rochester, New York.
2 Department of Obstetrics and Gynecology, University of Rochester School of Medicine and Dentistry, Rochester, New York.