LOINC Code 11983-4: Fetal Head Circumference derived from occipital-frontal diameter and outer-inner biparietal diameter (US)

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 Perimeter. It is commonly used with the system or sample type Head^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 from OFD&O-I BPD

What it does not mean

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

Key facts

• Fetal Head Circumference derived from occipital-frontal diameter and outer-inner biparietal diameter (US)
• Perimeter
• Derived from measures of occipital-frontal diameter and transaxial diameter assuming shape is an ellipse. The outer to inner transaxial, or biparietal, is used
• Biparietal diameter; Brain; by OFD+O-I BPD; Circum; Circumference; Cranial; Cranium; der US; Echoencephalogram; Echoencephalography; Echography; Fetal; Gyn; Gynecology; HC; Head Circumference; Intracranial; Length; OB; ObGyn; OBSTERICAL; OBSTERICAL.ULTRASOUND; Obstetrical; Obstetrics; Occipital-Frontal Diameter; Occipital-Frontal Diameter & biparietal diameter; Outer to Inner Biparietal Diameter; Point in time; QNT; Quan; Quant; Quantitative; Random; Skull; Sonogram; Sonograph; Sonography; 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

Frequently asked questions