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Direct Bilirubin, Amniotic Fluid — Spectrophotometry, Mass Concentration

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

Measures direct bilirubin in amniotic fluid, the fluid surrounding the fetus. Results are interpreted by your obstetric or maternal-fetal medicine team.

Quick summary

["This test measures bilirubin in amniotic fluid and is interpreted as part of the clinical pregnancy assessment."]

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

Key facts at a glance

LOINC
12476-8
Short code
Bilirub Amn Spectrp dir-mCnc
Synonyms
Bilirub Amn Spectrp dir-mCnc
Category
liver
Sample
fluid
Container
Sterile tube
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
direct-spectrophotometry
Specimen volume
2-5 mL
Stability
Room temperature: 2h, Refrigerated: 24h
Hemolysis max
300
TAT
4–24 hours
Order
routine

What is this test?

This test measures the amount of direct bilirubin in amniotic fluid, which surrounds the fetus during pregnancy. It is a laboratory analysis performed on fluid collected during a procedure such as amniocentesis.

Why might I need this test?

Amniotic fluid bilirubin may be measured in selected pregnancy evaluations, particularly when the care team is assessing the fetus or possible blood incompatibility. The reason for testing is best confirmed with your obstetric or maternal-fetal medicine clinician.

How is the test performed?

A laboratory uses a spectrophotometric method to measure bilirubin in the submitted amniotic fluid sample. The direct bilirubin result is reported as a mass concentration.

How do I prepare for the test?

No special preparation is usually needed for the laboratory analysis itself. Preparation depends on whether and how amniotic fluid will be collected, so follow the instructions provided by your pregnancy care team.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Amniotic Fluid Bilirubin

Frequently asked questions

Is this the same as a routine blood bilirubin test?
No. This test is performed on amniotic fluid, while routine bilirubin tests use a blood sample. The results are interpreted differently and are not interchangeable.
How is amniotic fluid obtained?
It is usually collected by amniocentesis, in which a clinician removes a small amount of fluid from around the fetus under ultrasound guidance.
Does an abnormal result mean the fetus has a specific condition?
Not by itself. Your clinician will consider the result along with gestational age, ultrasound findings, blood-group information, and other test results before explaining its significance.
  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