Blood Type ABO Grouping and Rho(D) Typing

Blood Type ABO Grouping and Rho(D) Typing

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Blood typing is used to determine an individual's blood group, to establish whether a person is blood group A, B, AB, or O and whether he or she is Rh positive or Rh negative.

Blood ABO Grouping and Rh Typing - Everything You Need to Know

Although blood has its unique red color, its chemistry can be varied from individual to individual. Some people have a certain type of blood and they cannot receive blood transfusions from people with who they are not compatible.

The blood typing or grouping is dictated by certain antibodies called antigens. These antigens are present on the surface of red blood cells or other tissues in the body. Keep reading to learn more about ABO grouping, Rh typing, and why they are important.

What Is ABO Grouping and Rh Typing?

Scientists have discovered more than 40 different types of blood in the human body. However, some of them are prevalent to most people, so we'll focus on them. For example, the 4 main types of blood are A, B, AB, and O.

This type of grouping or blood system is created based on the antigens present on the surface of red blood cells. People who have type A blood have the A antigen; people who have type B blood have the B antigen. Similarly, people who have type AB blood have both A and B antigens, and finally, people with type O blood have no antigens at all.

The Rh typing also comes into play here. Blood types can have 2 Rh options - positive or negative. Rh-positive blood has a specific antibody present on the red blood cells. Rh-negative blood doesn't have this antibody.

Delivering the wrong type of blood to a person can pose serious complications. There is a risk of blood clumping and agglutination. These conditions can be life-threatening as they tend to damage most of the tissues and organs in the body of the recipient.

How Does Blood Compatibility Work?

The immune system of each individual is capable of identifying the specific antigens present on the red blood cells. Blood compatibility is important when it comes to blood transfusions because if someone gets the wrong type of blood, his/her immune system starts to develop antibodies against it.

For example:

  • Type A people can receive from other people with type A blood or from people with type O. They can donate blood to people with type A and/or type AB blood
  • Type B people can receive from other people with type B blood or from people with type O. they can donate blood to people with type B and/or type AB blood
  • Type AB people can receive blood from anyone but they can only donate blood to other type AB individuals
  • Type O people can receive blood only from other individuals with type O. They can donate to everyone since their blood has no specific antigen present on red blood cells

Additionally, blood transfusions are also dictated by the Rh factor. For example:

  • Rh-positive people can receive blood from other individuals with Rh-positive blood or people with Rh-negative blood
  • Rh-negative people can only receive blood from other individuals with Rh-negative blood typing. They can safely donate to either Rh-negative or Rh-positive people

As you can see, there are 8 main types of blood out there if you consider the blood-specific antigen and the Rh factor. That's why it's important to know your blood type, so you know your compatibility in case of transfusions or medical emergencies.

When it comes to blood grouping distribution, about 38% of the US population is type O positive and 7% is type O negative. 34% percent is type A positive and just 6% is type A negative. The other blood groupings are small percentages, but these statistics are constantly changing over the years.

Type O blood is always a priority for blood banks and hospitals because this type of blood is the most prevalent. There is always someone who needs type O blood on a hospital bed. More specifically, Rh-negative type O blood is a universal donor as it can be transfused to everyone without the risk of harming recipients.

On the other hand, having Rh-positive type AB blood makes you a very lucky person. You can receive blood from anyone without damaging your system. This is called the universal recipient type of blood and only about 3% of people in the United States have it.

Why Is It Important to Know Your Blood Type?

There are multiple reasons why you should know your blood type. This is vital information that's inexpensive to find out. Here are some of these reasons:

Know Your Blood Donation Compatibility

Hospitals are almost always in great demand of blood, particularly those types that are difficult to find such as Rh-negative blood. If you get the chance and you're able, you should donate blood once per year.

Every blood bag is labeled and stored accordingly by hospitals and blood banks. This blood is useful during surgeries or for blood transfusions. If you know your blood type, you are more aware of how prevalent or how scarce it can be.

Know the Transfusion Compatibility

Knowing your blood type also helps with identifying possible donors or receivers in a specific circle of friends or among your family members. Remember that there are 8 different blood types out there if you consider the Rh factor.

If you have a particularly rare type of blood, it's good to know so you can find potential donors on time. Your body cannot receive blood from anyone and knowing the transfusion compatibility saves a lot of time and headaches.

For example, if a person receives incompatible blood, his or her immune system will start to develop antibodies to the antigens of the received blood. This is basically doing more harm than good. Blood transfusions are frequent during surgeries and a lot of complications can arise if the wrong type of blood is administered.

Similarly, if you ever need a blood transfusion, it's nice to know that you're compatible with someone in your family or circle of friends. In case of emergency, you can be the recipient or donor of blood to save someone's life or yours.

It's Useful for Pregnant Women

Although it rarely happens, some mothers might be Rh-negative and give birth to a Rh-positive baby. The baby inherits the positive antigen from a Rh-positive father. As a result, the mother's immune system might see the Rh positivity of the baby as a foreign substance and develop antibodies to it.

These antibodies could cross the placenta and cause massive damage to the internal organs and tissues of the newborn. This is called hemolytic disease and it can be prevented with the right treatment.

During pregnancy, doctors can do ABO grouping tests to determine if the mother and the baby are not blood compatible. If this is the case, doctors might choose to administer injections that protect the Rh antigen of the baby against the immune system of the mother.

These injections are administered throughout pregnancy and after giving birth. It will prevent hemolytic disease and other complications caused by having an incompatibility between the mother and the fetus.

Know Your Organ Donor Status

Not only blood can be put into another person's body, but also organs and/or tissues. In this case, there is also a compatibility issue and knowing your ABO grouping and Rh factor helps a lot. Doctors do a lot of tests to determine if a person is compatible with another before donating a portion of an organ.

For example, the liver is known to have amazing regenerative properties. It's possible to receive a liver transplant from someone else under certain conditions. However, the organ must be compatible with your body and your blood types must match too.

Apart from blood, organs, and tissues, bone marrow transplants are also popular and can be done successfully. Again, ABO grouping tests and other types of tests are required to determine the compatibility of bone marrow between the donor and the recipient.

How Can You Find Out Your Blood ABO Grouping?

Finding what type of blood, you have is done very easily with the help of a blood test. You can order a direct-to-consumer lab and go to a clinic to give a blood sample. The results are emailed back to you in a few days or even quicker.

It takes medical science just a few minutes to determine your ABO grouping and Rh factor. This information is useful for each individual to know his/her compatibility with family members, friends, and so on.

In case of an emergency, it's good to know that you can donate blood to your sister or you can receive it from your closest friend because your blood types are compatible. Also, you don't have to fast before testing your blood type and this makes it more convenient for the general public.

Find Your Blood Type Today!

For an accurate and inexpensive blood grouping test, go to and order the ABO grouping blood test. You earn reward points from purchasing from DiscountedLabs and you get the results back very quickly!



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  1. Go to the "Find a Location" page to find the closest lab location. No need to make an appointment since walk-ins are welcomed. Once you have identified your closest location, go to step 2.

  2. Go to "Choose a Test" and add your selection (s) in the shopping cart. If you prefer to save money on bundled tests, we have created "Lab Test Panels" that can help you decide what to order.

  3. If you have a discount coupon code, add it to your cart.

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  7. Print lab request form that you downloaded.

  8. Take that form to the closest location. Get your blood drawn.

  9. You will receive an email when the results are ready for you to download.

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