Blood draw
Blood Group and Rhesus Factor
ABO blood group and Rhesus(D).
€ 78,00
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Blood count and blood group · Blood
Rhesus D (RhD)
Determines whether you are Rhesus D positive or negative; important in pregnancy and for a blood transfusion.
At a glance
- Measured in blood
- In 1 test panel
- No special preparation
Explanation
Rhesus D (RhD): what is measured?
The Rhesus D blood group (RhD, formerly the rhesus factor) is a protein that is either present or absent on the outside of your red blood cells. If the protein is present, you are RhD positive; if it is missing, you are RhD negative. Your RhD blood group is inherited and does not change. Together with the ABO blood group, it forms the blood group as it is usually named, for example 'O negative'.
What can it detect?
- Your Rhesus D blood group: positive or negative
- Whether extra tests and an anti-D injection may be needed in a (future) pregnancy (if RhD negative)
Result
What does the result mean?
Positive result
RhD positive means that the Rhesus D protein is present on your red blood cells; this applies to about 85 percent of people. It is not a disease and has no consequences for your health. In pregnancy, RhD positive in the mother is not a problem, even if the child is RhD negative. For a blood transfusion, you can receive both RhD positive and RhD negative blood.
Negative result
RhD negative means that the Rhesus D protein is missing; this applies to about 15 percent of people. For your own health it makes no difference. It does matter if you are or become pregnant with an RhD positive child: your body can then make antibodies against the child's blood, which in a next pregnancy can cause anemia and jaundice in the baby (rhesus disease). That is why RhD negative pregnant women get an extra blood test in week 27 for the child's blood group and, if the child is RhD positive, an anti-D injection in week 30 and after the birth, which largely prevents this. For a blood transfusion you also receive RhD negative blood, because otherwise you may start making antibodies.
After an abnormal result
If you are RhD positive, no follow-up is needed. If you are RhD negative, there is nothing to do now; in a pregnancy, the midwife or gynecologist follows the national policy with an extra blood test in week 27 and, if needed, an anti-D injection.
Reliability
How reliable is the test?
The RhD test in the laboratory is reliable, and an RhD blood group once determined does not change. In a small share of people, the RhD protein is weak or built differently (weak or partial D); the result can then be unclear or differ between laboratories. Midwives and hospitals do not use this result: every pregnant woman gets the national blood test at around 12 weeks with its own RhD test, and for a transfusion the hospital always determines the blood group itself.
What can affect the result?
- Weak or partial variants of the RhD protein can give an unclear result; in pregnancy or before a transfusion, additional tests are done for this.
- After a blood transfusion or a stem cell or bone marrow transplant, the measured blood group can differ from the blood group you were born with.
- The test says nothing about antibodies against blood groups or about other rhesus blood groups, such as Rhesus c, which are also tested in pregnancy.
Who it is for
Who is the test useful for?
Useful for
Useful if you want to know your RhD blood group out of curiosity or for your own records, for example when planning to have children. Medically, testing in advance is not needed: every pregnant woman gets the test free of charge in the national blood test at around 12 weeks, and for a transfusion the hospital determines the blood group itself.
How common is it?
About 85 percent of people in the Netherlands are RhD positive and 15 percent RhD negative. This comes to about 27,000 RhD negative pregnant women per year, about 60 percent of whom are pregnant with an RhD positive child.
Sanquin and the RIVM (pns.nl)
Drawbacks and risks
- The result can give the impression that the blood group test at the midwife is unnecessary; it is always done again and is needed for the right care during pregnancy.
Get tested
Rhesus D (RhD): test panels
Rhesus D (RhD) is part of these test panels. You order online and have your blood drawn at a collection point or collect the sample at home.
Evidence
Sources
This explanation is based on Dutch guidelines and independent information. It is general information, not a diagnosis. Discuss an abnormal result with your GP.
More about risks and resultsMore explanations
Other tests: Blood count and blood group
- ABO blood group
- Basophils
- Eosinophils
- Erythrocytes (red blood cells)
- Hematocrit (Ht)
- Hemoglobin (Hb)
- Hemoglobin electrophoresis
- Leukocytes (white blood cells)
- Lymphocytes
- MCH
- MCHC
- MCV