What are blood groups and what is RH factor?

Knowing your blood types and RH factor is crucial, especially if you plan to get a blood transfusion or you are pregnant. The blood types and the RH factor must be determined.

What are blood groups and what is RH factor?

Based on the presence or absence of antibodies and hereditary antigenic compounds on the surface of red blood cells, blood types are categorized.

Content:

How are blood groups determined?
How the ABO system is based today
What are the blood groups?
What is the RH factor?
The significance of determining blood group and RH during pregnancy
Distribution of blood groups in Romania:

How are blood groups determined?

Blood groups were first discovered by an Austrian physician, Carl Landsteiner, who worked at the Pathological-Anatomical Institute of the University of Vienna - now the Medical University of Vienna.

In 1900, he discovered that blood serum from different people would pool when mixed in test tubes.

This was the first instance of human blood varying, according to science. He made the categorical difference that a person's blood would only clump with that of particular persons the next year, in 1901. He divided human blood into three groups—group A, group B, and group C—based on this, creating the classification. He said that blood from group A never engages in combat with blood from group B. Similar to group A, group B blood clumps together. In contrast to group A and B, group C blood clumps together. In 1930, Landsteiner won the Nobel Prize in Physiology or Medicine for his discovery of blood types.

How the ABO system is based today

Blood is made up of red blood cells, white blood cells and platelets united in a liquid called plasma. Antibodies and antigens in the blood are used to determine blood type.

Antibodies are proteins found in plasma. They are a component of the body's built-in defense mechanism. They recognize foreign substances, such as bacteria, and alert the immune system, which destroys them.

Red blood cells' outer layer contains protein molecules known as antigens. In other words, the ABO system is built on two agglutinogens (antigens) (A, B) and two agglutinins (antibodies) (anti-A and anti-B). The ABO blood group system divides blood types based on the many antigens and antibodies found in plasma and red blood cells. The ABO system along with Rh antigen status is used to determine which blood type or blood types will be suitable for a safe transfusion of red blood cells.

A person's body will reject and assault new red blood cells if they are given antigens that are not already in place in their system.

What are the blood groups?

There are four ABO blood groups:

Group A: the surface of the red blood cells contains antigen A, and in the plasma, there is an anti-B antibody. The anti-B antibody will attack the blood cells that contain the B antigen.
Group B: The surface of the red blood cells contains antigen B, and in the plasma, there is an anti-antibody. The A antibody will attack the blood cells containing the A antigen.
Group AB: Red blood cells contain both A and B antigens, but neither A nor B antibodies nor their corresponding peptides are present in the plasma. Any ABO blood type can exist in a type of AB person.
Group O: Plasma contains both anti-A and anti-B antibodies, but the surface of red blood cells does not contain type A or B antigens. Because these antigens are not present, a person with any ABO blood type can have this blood type.

What is the RH factor?

What are blood groups and what is RH factor?

Red blood cells sometimes have another antigen, a protein called the RhD antigen. If it is present, your blood type is RhD positive. Your blood type is RhD negative if it is absent. Thus, there are 8 different blood types that a person can have:

RhD positive (A+)
RhD negative (A-)
B RhD positive (B+)
B RhD negative (B-)
O RhD positive (O+)
O RhD negative (O-)
AB RhD positive (AB+)
AB RhD negative (AB-)

The significance of determining blood group and RH during pregnancy

The mother may not have the same blood type or Rh factor as the child if the parents have different blood types. If the mother has Rh-negative blood and the baby is Rh-positive, this may pose a risk during pregnancy and delivery.

A small number of red blood cells from the fetal circulation may cross the placenta and enter the mother's circulation. An anti-RhD antibody can then develop in the mother's plasma in a process known as sensitization.

A problem can arise if this antibody then recognizes a "foreign" antigen in the blood cells of the fetus. As a form of protection, antibodies may start to target the developing foetus' red blood cells.

In some circumstances, there may be severe jaundice and even potential brain damage.

An injection of immunoglobulin G against RhD can prevent the mother's body from producing this antibody and reduce the impact of a sensitization event on the fetus.

If a woman has Rh negative blood, the doctor may give anti-D immunoglobulin at weeks 28 and 34 as a contraceptive, according to the World Health Organization (WHO).

Blood tests during pregnancy can predict possible risks, so it is important to check that the blood type of the fetus matches that of the mother.