LOINCActiveObservation

LOINC Code 33191-8: Fetal Thorax Diameter product derived by US

33191-8 is a LOINC code used to identify Fetal Thorax Diameter product derived by US in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Diameter product. It is commonly used with the system or sample type Thorax^Fetus.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Diameter product. It is commonly used with the system or sample type Thorax^Fetus.

When is it used?

  • Used in lab systems, EHRs, and clinical data exchange.
  • May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
  • Status: ACTIVE
  • Order vs observation: Observation
  • Method: US.derived

What it does not mean

  • The code identifies the observation or test, not the actual result.

Key facts

  • Fetal Thorax Diameter product derived by US
  • Diameter product
  • APADxTAD; AxT; der US; DIA; Diam; Diam prod; Echography; Fetal; FTA; Gyn; Gynecology; OB; ObGyn; OBSTERICAL; OBSTERICAL.ULTRASOUND; Obstetrical; Obstetrics; Point in time; Product of anterior-posterior abdominal diameter & transverse abdominal diameter; QNT; Quan; Quant; Quantitative; Random; Sonogram; Sonograph; Sonography; Thoracic; ULS; Ultrasound

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

Fetal Thorax Diameter product derived by USFet Thorax Area Diam prod der USDiameter productOB.USAreaPtThorax^fetus

Frequently asked questions

Code details

Code33191-8
SystemLOINC
Display nameFetal Thorax Diameter product derived by US
DescriptionDiameter product
Short nameFet Thorax Area Diam prod der US
ComponentDiameter product
PropertyArea
TimingPt
System (specimen)Thorax^Fetus
ScaleQn
MethodUS.derived
ClassOB.US
Example unitsmm2
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.09
Last changed2.70

Part names

Diameter productAreaPtThorax^fetusQnUS.derivedPoint in time (spot)Ultrasound.derived

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

LOINC Code 33191-8 | HealthAssure