Skip to content

: Proline, Amniotic Fluid, Substance Concentration

Published: August 9, 2026Updated: August 16, 2026

: This test measures the concentration of proline, an amino acid, in a sample of amniotic fluid. It is generally used in specialized evaluation of fetal amino acid metabolism rather than as a routine test.

Quick summary

[": Proline in amniotic fluid is measured to help assess certain inborn errors of amino acid metabolism in the developing fetus."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
27033-0
Short code
Proline Amn-sCnc
Synonyms
Proline Amn-sCnc
Category
chemistry
Sample
fluid
Container
Sterile tube
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
2-5 mL
Stability
Room temperature: 2h, Refrigerated: 24h
Hemolysis max
300
TAT
4–24 hours
Order
routine

: What Is Being Measured

: Proline is one of the amino acids, the building blocks of proteins. This test determines how much proline is present in amniotic fluid, the fluid surrounding a fetus during pregnancy.

: Why the Test May Be Ordered

: Measuring amino acids in amniotic fluid can be part of an evaluation when there is concern about how a fetus is processing amino acids. It is a specialized test and is usually interpreted alongside other amino acid measurements and clinical findings.

: How the Sample Is Collected

: Amniotic fluid is collected by a procedure called amniocentesis, in which a small sample of fluid is withdrawn with a thin needle guided by ultrasound. This procedure is performed by a healthcare professional.

: How Results Are Interpreted

: Results are reported as the concentration of proline in the fluid. Because normal levels change with gestational age and laboratory methods differ, results are best interpreted by the ordering clinician in the context of the pregnancy and other test results.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

: NONE

Frequently asked questions

: Is this a routine pregnancy test?
: No. Measuring proline in amniotic fluid is a specialized test, not part of standard prenatal screening, and is typically used only when a metabolic concern is being evaluated.
: Does an abnormal result always mean there is a problem?
: No. Results can vary with gestational age, laboratory method, and sample handling, so findings must be assessed by a clinician along with other tests and clinical information.
: How is the amniotic fluid sample obtained?
: The sample is obtained through amniocentesis, a procedure performed by a trained healthcare professional using ultrasound guidance.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy