Rh factor is an important antigen present in the blood of certain people, whose presence means that the classification will be Rh+. Individuals who do not naturally possess such an antigen receive the Rh- classification.
The designation "Rh" is an abbreviation of the monkey name "Rhesus", in which scientists Landsteiner and Wiener first identified the presence of the antigen they called the "Rh factor".
Through this experiment carried out in 1940 with the Rhesus monkey, it was also possible to verify the production of antibodies called “anti-Rh”.
To determine whether a person's Rh is positive or negative, a solution containing Rh antibodies should be added to a drop of blood from the person concerned. If there is agglutination of the red blood cells, the person has Rh+, if not, the person has Rh- blood.
The ABO System is essential as it indicates the four blood groups existing in humans: A, B, AB and O. It is known that in the ABO human blood groups, red blood cells have two types of antigens, which are called agglutinogens, which are A and B. Plasma can have two antibodies (agglutinins), which are anti-A and anti-B.
Importance of blood group in blood transfusions and pregnancy
Identifying an individual's blood group (O+, A+, B+, O-, A-, B-, AB+, AB-) is important to determine the type of blood transfusion, and also to prevent a newborn to acquire a specific disease called "Fetal Erythroblastosis" (or "Rhesus Disease", "Rh Incompatibility Hemolytic Disease", "Rh Incompatibility Hemolytic Disease" Newborn").
In blood donations, each person can only receive or donate a specific blood type: types O- are considered “universal donors” and types AB+ are considered “universal recipients”. A transfusion error can lead to reactions that lead to death.
The Rh factor influences the pregnancy of Rh- women who have had contact with Rh+ blood (through the father's Rh+ blood, which can generate a Rh+ child).
In a second pregnancy, the Rh+ blood of the fetus may mix with that of the mother, stimulating the production of antibodies in her Rh that will destroy the baby's blood cells and may cause death from anemia, jaundice or failure cardiac arrest.
Therefore, it is important that the situation is diagnosed in time so that the most appropriate treatment is carried out to avoid complications with the baby.