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Published on: January 7, 2014
A Lexicon for First-Trimester US: Society of Radiologists in Ultrasound Consensus Conference Recommendations
Shuchi K Rodgers1, Mindy M Horrow1, Peter M Doubilet1
1From the Department of Radiology, Thomas Jefferson University, Philadelphia, Pa (S.K.R.); Department of Radiology, Einstein Healthcare Network/Jefferson Health, Philadelphia, Pa (M.M.H.); Department of Radiology, Brigham and Women's Hospital/Harvard Medical School, Boston, Mass (P.M.D., M.C.F.); Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, Utah (A. Kennedy); Department of Radiology and Radiological Sciences and Department of Obstetrics and Gynecology, Vanderbilt University, Nashville, Tenn (R.A.); American College of Obstetricians and Gynecologists, Newark, NJ (K.B.); Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Tex (L.D.); Department of Obstetrics and Gynecology, Pennsylvania State University, University Park, Pa (S.K.H.); Department of Radiology, Stanford University, Stanford, Calif (A. Kamaya); Division of Child Health, University of Arizona College of Medicine Phoenix, Phoenix, Ariz (A. Koyama); Department of Emergency Medicine, Columbia University, New York, NY (P.C.L.); Department of Radiology and Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Mich (K.E.M.); Department of Radiology, Mayo Clinic Arizona, Phoenix, Ariz (T.M.); Department of Obstetrics and Gynecology, University of South Florida, Tampa, Fla (S.G.O.); Department of Radiology, University of North Carolina, Chapel Hill, NC (K.O.); Department of Diagnostic Radiology, Oregon Health & Sciences University, Portland, Ore (R.S.); Department of Obstetrics and Gynecology, University of Pennsylvania, Philadelphia, Pa (S.S.); and Department of Radiology and Biomedical Imaging and Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Francisco, 1001 Potrero Ave, 1X57, San Francisco, CA 94110 (L.M.S.).
Abstract:
The Society of Radiologists in Ultrasound convened a multisociety panel to develop a first-trimester US lexicon based on scientific evidence, societal guidelines, and expert consensus that would be appropriate for imagers, clinicians, and patients. Through a modified Delphi process with consensus of at least 80%, agreement was reached for preferred terms, synonyms, and terms to avoid. An intrauterine pregnancy (IUP) is defined as a pregnancy implanted in a normal location within the uterus. In contrast, an ectopic pregnancy (EP) is any pregnancy implanted in an abnormal location, whether extrauterine or intrauterine, thus categorizing cesarean scar implantations as EPs. The term pregnancy of unknown location is used in the setting of a pregnant patient without evidence of a definite or probable IUP or EP at transvaginal US. Since cardiac development is a gradual process and cardiac chambers are not fully formed in the first trimester, the term cardiac activity is recommended in lieu of 'heart motion' or 'heartbeat.' The terms 'living' and 'viable' should also be avoided in the first trimester. 'Pregnancy failure' is replaced by early pregnancy loss (EPL). When paired with various modifiers, EPL is used to describe a pregnancy in the first trimester that may or will not progress, is in the process of expulsion, or has either incompletely or completely passed. © RSNA and Elsevier, 2024 Supplemental material is available for this article. This article is a simultaneous joint publication in Radiology and American Journal of Obstetrics & Gynecology. All rights reserved. The articles are identical except for minor stylistic and spelling differences in keeping with each journal's style. Either version may be used in citing this article. See also the editorial by Scoutt and Norton in this issue.
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