Perinatology Research Branch, Division of Obstetrics and Maternal-Fetal Medicine, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, U.S. Department of Health and Human Services (NICHD/NIH/DHHS), Bethesda, Maryland, and Detroit, Michigan, United States of America. Department of Internal Medicine, Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, Michigan, United States of America. Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan, United States of America. Department of Epidemiology and Biostatistics, Michigan State University, East Lansing, Michigan, United States of America. Center for Molecular Medicine and Genetics, Wayne State University, Detroit, Michigan, United States of America. Detroit Medical Center, Detroit, Michigan, United States of America. Department of Obstetrics and Gynecology, Wayne State University School of Medicine, Detroit, Michigan, United States of America. Department of Computer Science, Wayne State University College of Engineering, Detroit, Michigan, United States of America. Metabolon Inc., Raleigh-Durham, North Carolina, United States of America. Department of Obstetrics and Gynecology, Soroka University Medical Center, School of Medicine, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel. Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, United States of America. Maternity Department "D," Division of Obstetrics and Gynecology, Soroka University Medical Center, School of Medicine, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer-Sheva, Israel.