1. 1Department of Obstetrics and Gynecology, Mayo Clinic, Rochester, Minnesota.
2. 2Department of Quantitative Health Sciences, Mayo Clinic Rochester, Minnesota.
3. 3Department of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota.
4. 4Division of Anatomic Pathology, Mayo Clinic, Scottsdale, Arizona.
5. 5Department of Quantitative Health Sciences, Mayo Clinic, Jacksonville, Florida.
6. 6Department of Gastroenterology and Hepatology, Mayo Clinic, Scottsdale, Arizona.