Blood is a unique substance that consists of plasma and uniform substances. Depending on its composition, several types are distinguished. They are classified by different systems, among which the AB0 system is most often used. On it distinguish the first, which is also called the universal blood group, as well as the second, third and fourth groups.
Human plasma contains two types of agglutinins and two types of agglutinogens. They can be present in the blood in different combinations and this sets the blood group:
- So, according to the system AB0, if there are α and β, then this is the first group, also it is denoted by the number "0". It is she who is called the universal blood group.
- The second contains proteins A and β and is designated “A”.
- The third consists of B and α and is designated "B".
- The fourth includes A and B and is designated as "AB".
In addition to agglutinins and agglutinogens, there is a specific antigen in the blood located on the surface of red blood cells. If available, they speak of a positive Rhesus factor. If there is no antigen, then the person has a Rhesus negative.
Group compatibility
The compatibility of blood groups began to be discussed in the last century. At that time, gamotransfusion was used, which allowed to restore the volume of circulating blood in the body. After a series of unsuccessful and successful experiments, scientists came to the conclusion that transfused blood may be incompatible, and further observations showed that the blood of one group and one Rh factor may not be suitable for the patient with the same data.
However, during the experiments it was possible to find a universal blood group, which is ideal for all other species. This kind can be transfused with recipients from the second, third and fourth group. Also, during testing, a universal blood group was identified, into which any other can be transfused - this is the fourth group with a positive Rh factor.
First group
According to statistics, about 40% of the world's people have the first blood group. All of them are divided into two groups: Rh-positive 0 (I) and Rh-negative 0 (I). The latter have a universal blood group and a Rh factor that suits everyone. In other words, the materials of these people can be transfused to patients with any other group. This visually looks like this:
| 0 (I) rhesus neg. | 0 (I) Rhesus pos. | A (II) rhesus neg. | A (II) Rhesus pos. | B (III) rhesus neg. | B (III) Rhesus pos. | AB (IV) rhesus neg. | AB (IV) rhesus pos. |
0 (I) rhesus neg. | + | + | + | + | + | + | + | + |
0 (I) Rhesus pos. | | + | | + | | + | | + |
A universal donor with first positive blood is compatible with other groups, but only with positive Rhesus.
Nowadays, the first group with transfusion of the recipient with another group is rarely used. If a situation suddenly arises in which it is necessary to pour it into the patient, then, as a rule, they are used in small quantities - not more than 500 ml.
If the recipient has a universal 1 blood group, the donor can only be with the same blood, i.e.:
- 0 (I) Rh- is only compatible with 0 (I) Rh-;
- 0 (I) Rh + is compatible with 0 (I) Rh- with 0 (I) Rh +.
When transfusion, the peculiarities of the donor and recipient are taken into account, because even with the same group and Rhesus, the fluids are not always compatible.
Second group
The second group has restrictions on use. It can be used only by people with the same data and the same rhesus. So, for blood transfusion, the blood of the second group with negative Rhesus is used in people with the second group with both positive and negative Rhesus. A positive rhesus fluid is used only in recipients with the same Rh. You can also pour the first group into the second.
Third group
This option is compatible not only with the third, but also with the fourth and first groups. A universal donor can donate blood for patients with B (III).
If the donor has a third group, then his blood will be compatible with the following recipients:
- With Rh-positive blood donor, it can be transfused for people fourth and third positive.
- In case of negative Rhesus: blood can be used for people with the third and fourth both positive and negative groups.
Fourth group
Asking the question of which blood type is universal, one can answer that there are two of them. The first group with negative Rhesus makes it possible to save the lives of all people, regardless of group and Rhesus. But people with the fourth group and positive rhesus are universal recipients - they can be infused with any blood, with any rhesus.
If the recipient will have a negative Rhesus, then any group with only a negative Rhesus is poured into it.
The effect of blood type on the conception of a child and pregnancy
At the conception of a child, the blood type does not matter, but the Rh factor is very important. If the mother has negative blood, and the baby has positive, then throughout the pregnancy there is an immunological reaction in which protein is produced in the mother’s blood. If, during repeated pregnancy, the fetus again has a positive Rh, then in the woman's body a reaction of agglutination and hemolysis of red blood cells will begin to occur. This situation is called Rhesus conflict.
Therefore, after the first pregnancy, a woman is recommended to introduce anti-Rhesus globulin to break the immunological chain.
Other blood types
It is interesting that in the fifties of the last century, scientists revealed another blood group, which can not be attributed to either the first or any other. It is called Bomei, at the place where carriers of this group are found.
The peculiarity of this group is that it does not contain antigens A and B. But antigen H is also absent in its serum, which can cause serious difficulties, for example, during the determination of paternity, since the baby will not have any antigen in the blood his parents. This group is very rare in the world (only 0.01%), and the chromosomal mutation is to blame for its appearance.