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
(IUP) is defined as a pregnancy implanted in a normal location within the uterus. In contrast, an
(EP) is any pregnancy implanted in an abnormal location, whether extrauterine or intrauterine, thus categorizing cesarean scar implantations as EPs. The term
is used in the setting of a pregnant patient without evidence of a
or
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
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
(EPL). When paired with various modifiers,
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
This article is a simultaneous joint publication in
and
. 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.