In rare cases, if Rh disease is not treated, the baby may die. An Rh test is done in early pregnancy to check a woman's blood type. If she is Rh-negative, she can get a shot of Rh immunoglobulin that almost always prevents sensitization from occurring. Problems from Rh sensitization have become very rare since Rh immunoglobulin was developed. In general, there's nothing you have to do before this test, unless your doctor tells you to. A health professional uses a needle to take a blood sample, usually from the arm.
When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch. There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.
The following table shows the compatibility of blood types between blood donors and recipients. Read the table as follows: A person who has A-negative blood can receive A-negative or O-negative blood. Minor antigens other than A, B, and Rh on the red blood cells are also checked for a match before a blood transfusion. Gabica MD - Family Medicine. Author: Healthwise Staff. Medical Review: E. This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.
Your use of this information means that you agree to the Terms of Use and Privacy Policy. Learn how we develop our content. Testing difficulties can cause exceptions to the above patterns.
ABO blood typing is not sufficient to prove or disprove paternity or maternity. Now that you know how your blood type can help recipients, please schedule an appointment to donate today.
Blood Types. Download Guide. Blood Types and Transfusion Each year 4. Every 2 seconds someone in the US needs a blood transfusion. Use the interactive graphic below to learn more about matching blood types for transfusions. Donate and find out. While several blood group systems are used to type your blood, ABO is the most important. Your ABO type is based on the presence or absence of two antigens A and B on the surface of red blood cells.
That leaves us with eight possible blood types:. Each of these eight types is unique. Blood types determine who you can give blood to and receive blood from. Which type of donation is best for you is determined by your blood type, as well as patient need.
Red blood cells sometimes have another antigen, a protein known as the RhD antigen. If this is present, your blood group is RhD positive. If it's absent, your blood group is RhD negative. In most cases, O RhD negative blood O- can safely be given to anyone. It's often used in medical emergencies when the blood type is not immediately known.
It's safe for most recipients because it does not have any A, B or RhD antigens on the surface of the cells, and is compatible with every other ABO and RhD blood group. To work out your blood group, your red cells are mixed with different antibody solutions. If, for example, the solution contains anti-B antibodies and you have B antigens on your cells you're blood group B , it will clump together.
If the blood does not react to any of the anti-A or anti-B antibodies, it's blood group O. A series of tests with different types of antibody can be used to identify your blood group. If you have a blood transfusion — where blood is taken from one person and given to another — your blood will be tested against a sample of donor cells that contain ABO and RhD antigens.
0コメント