Serum or Plasma Type (Blood Grouping) – ABO and Rh Factor
This test determines your blood type (A, B, AB, O) and Rh factor (positive or negative), which is essential for safe blood transfusions and pregnancy care.
["Your blood type affects compatibility with blood donations and medical treatments."]
Key facts at a glance
- LOINC
- 88722-4
- Short code
- S pneum Sertyp Islt
- Synonyms
- S pneum Sertyp Islt
- Category
- coagulation
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Your Blood Type Matters in Everyday Life
Your blood type is determined by specific proteins (antigens) on your red blood cells. For example, if you have A antigens, your blood type is A. If you lack these proteins, your type is O. The Rh factor (positive or negative) indicates whether your blood has another protein called D antigen. This test is critical for preventing dangerous reactions during blood transfusions or pregnancy complications like hemolytic disease of the fetus and newborn (HDFN).
How the Test Works
Blood is drawn and tested using immunoassay methods to detect the presence or absence of A, B, and Rh antigens. The results identify your exact blood type and Rh status, which are recorded on your medical records for future use.
When You Might Need This Test
You may need this test for routine blood work, before a blood transfusion, during pregnancy (especially in the first trimester), before surgery, or if you’re planning to donate blood. Some medical conditions or procedures may also require repeated testing.
What to Expect Before the Test
No special preparation is needed. You’ll have a small needle inserted into your arm to draw a few drops of blood. The process usually takes a few minutes. If you’re pregnant, your healthcare provider may recommend this test early in your pregnancy to check for Rh incompatibility.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
ABO/Rh Blood Type Test
Frequently asked questions
This test is foundational for ensuring safe medical treatments, such as transfusions, and is vital during pregnancy to monitor for potential complications like Rh isoimmunization, which can affect the health of your baby.
Your blood type results are typically available within a few hours to a day, depending on your lab’s processing time. They’re usually sent directly to your healthcare provider for review.
Can I get my blood type tested at home? Some at-home kits are available, but they may not be as accurate as lab tests and should not replace professional medical evaluation.
Sources
- 1
- 2Lab Tests OnlineSource
- 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