Aborhpnlbld
A blood test that determines your blood group (A, B, AB, or O) and Rh factor (positive or negative).
{"Identifies your ABO blood type (A, B, AB, or O)","Determines your Rh factor (positive or negative)","Essential for blood transfusions and pregnancy care","Used to ensure blood compatibility between donor and recipient","A simple blood test with no special preparation needed"}
Key facts at a glance
- LOINC
- 34530-6
- Short code
- ABO/Rh
- Synonyms
- ABO + Rh Pnl Bld
- Category
- chemistry
- Sample
- serum
- Container
- EDTA lavender top tube (whole blood) - Note: Blood typing is performed on whole blood, not serum, as ABO and Rh antigens are expressed on red blood cell membranes
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Serologic agglutination (tube technique) or gel column assay
- CPT
- 86900 (ABO typing); 86901 (Rh typing)
- SNOMED
- 1441002
- Specimen volume
- 3-5 mL whole blood (minimum 1 mL for pediatric samples)
- Stability
- Room temperature (20-25°C): 72 hours; Refrigerated (2-8°C): 7 days. Do not freeze whole blood specimens.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 1–4 hours
- Order
- routine
What is this test?
The ABO and Rh blood type test is a routine blood test that identifies your blood group and Rh factor. Your blood type is determined by the presence or absence of certain antigens (proteins) on the surface of your red blood cells. The ABO system classifies blood into four types: A, B, AB, and O. The Rh system determines whether you are Rh-positive or Rh-negative.
Why is it important?
Knowing your blood type is crucial for several medical situations: if you ever need a blood transfusion, doctors must give you compatible blood to prevent a dangerous immune reaction. During pregnancy, knowing the Rh status is essential to prevent complications between the mother and baby. Blood type information is also useful for organ transplants and for understanding certain health risks.
How is the test performed?
A healthcare professional will draw a small blood sample from a vein in your arm. The blood sample is then sent to a laboratory where it is tested with specific antibodies to determine your blood type. You do not need to fast or make any special preparations before this test.
Understanding your results
Your test results will show your ABO blood type (A, B, AB, or O) and your Rh factor (positive or negative). For example, if you have type A positive blood, it means you have A antigens on your red blood cells and the Rh factor protein. If you have type O negative blood, you have neither A nor B antigens and lack the Rh factor. Type O negative is known as the universal donor type, while type AB positive is the universal recipient.
Reference range
Valid ABO group (A, B, AB, or O) and Rh type (positive or negative) with expected reactions for each antigen. Results must show clear, interpretable agglutination patterns.N/A
No special preparation required. Patient may eat and drink normally before specimen collection. Inform laboratory of recent blood transfusions (within last 3 months) as donor red cells may interfere with typing.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
The ABO and Rh blood type test is fundamental in transfusion medicine to ensure blood compatibility. Incompatible blood transfusions can cause severe, life-threatening immune reactions. For pregnant women, Rh-negative mothers may need special care if their baby is Rh-positive to prevent Rh disease, which can affect future pregnancies. Blood type information is also used in paternity testing and may play a role in understanding susceptibility to certain diseases.
Frequently asked questions
Does my blood type change over time?
Is it painful?
How long does it take to get results?
Why is Rh-negative blood special?
Do I need to know my blood type?
Sources
- 1
- 2
- 3
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.
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