Where to find out blood types: your own and your child, free methods and express methods. How to find out your blood type? Blood type analysis: where to do it

In a person's life, various unforeseen situations can occur: accidents, accidents. For quick assistance, the doctor needs to know the basic medical data of the patient. Experts tell you how to find out the blood type easily and quickly.

Why might you need

A group is an ordinal number determined by the presence or absence of certain antigens in red blood cells. You need to know it in the following cases:

• during blood transfusion, during the search for a suitable donor for the recipient and the exclusion of their incompatibility;
• when planning pregnancy - to prevent the Rh-conflict of the mother and child;
• during preparation for surgery.

A blood type, which is determined in the laboratory, will help you find a suitable donor. Only in this case, the transfusion will not cause rejection and complications. Not all blood types can mix with each other. So, the carrier of the first group is a universal donor for all people, and the blood of the second group can be transfused only to patients with the same or group 4, the latter are the best recipients, they can be transfused with any blood.

In rare cases, during pregnancy, immune conflicts occur between mother and child. The expectant mother should be tested for antibodies and checked regularly by her doctor.

An indicator such as the Rh factor is important.

Timely determination of the Rh factor in the blood will prevent the Rh conflict in a future woman in labor.

How to prepare for the test

Before determining the blood type and Rh factor, you must:

• competently build your diet - do not overeat, drink plenty of clean water;
• inform the doctor about taking medicines and drugs;
• avoid stressful situations and physical overload;
• stop smoking and drinking alcoholic beverages.

Physiotherapy procedures will also have to be temporarily postponed. Experts recommend that you stop eating 8-12 hours before donating blood. Tests are taken early in the morning, so such fasting will not bring discomfort to a person. After receiving the results, it is recommended to check the blood again. This will help ensure the accuracy of the analysis.

How is the blood type determined in the clinic

In immunological laboratories, blood is tested for the Rh factor and its group affiliation is determined. These laboratories operate in special medical centers and some hospitals. People who are thinking about how to get to know their group can apply to these institutions.

For a quick diagnosis, the patient can contact a general practitioner at his place of residence. The doctor will issue a referral with which the person will come to the treatment room on the appointed day. The results will be ready in 2-3 working days, the tests are free of charge. In private clinics, a referral for testing is not required: blood can be donated here with or without an appointment. The laboratory assistant will tell you about the timing of the receipt of the finished results, but often they are issued the next day.

For the study, a small amount of blood is taken from the patient from the cubital vein. For similar purposes, in the maternity hospital, newborns take blood from a vein in the head. In both cases, the algorithm for determining the blood group is the same: blood mixed with a special solution is placed in a test tube, and then in a centrifuge. During this procedure, under the action of agglutinins, a precipitate is formed. A saline solution with a concentration of 3% is added to the container with the working material.

When recognizing a blood group, the determination method remains the same. Today, physicians still use the standard AB0 system. This system serves as the basis for a special test to determine the group and Rhesus. Letters A and B denote special lipids, also referred to as agglutinogens.

Requires 2 blood units to study.

The anti-A reagent is added to the first, and the anti-B reagent is added to the other. The presence of antibodies indicates a particular group.

There are common ways to determine the Rh factor. If, after shaking the liquid in a centrifuge, white flakes stand out on the surface, Rh + is diagnosed. When a pink liquid forms in a test tube, experts conclude that the patient's Rh is negative. This method of determining the Rh factor allows you to get a guaranteed correct result.

What technique is used

There is a single technique for determining the group and the Rh factor. During the study, agglutinogens - antibodies are used. There may be a positive or negative reaction. There are 4 options for the final results. It:

• complete absence of agglutination in 4 working cells, indicating the first group;
• lack of the desired reaction in cells 1 and 3, or the second group;
• group 3 in the absence of agglutination in cells 1 and 2;
• the presence of agglutination in cells 1, 2, 3 - 4 group.

The ABO system allows you to find out the necessary information in the shortest possible time. This method of determining the blood group has proven itself and is used in most medical centers.

How to find out blood type without tests

Today, each person can independently determine their blood group without going to a medical institution. You can solve the problem by looking at the relevant information in the medical records of your parents. Girls inherit their father's group, and boys inherit their mother's. Parents with identical indicators give birth to children with the same data. The following table will help you get the necessary information, knowing the data of the parents:

The necessary information may be contained in a person's personal medical record, located in the clinic at the place of residence. You can find out the information in the registry of the medical institution.

You can check your data without analysis in the hospital using a special test. To conduct a study at home, you must purchase a kit consisting of several components:

• tablets with 5 holes, with which you can find out the Rh factor of the blood and the group;
• sampling tools;
• glass sticks for mixing liquids;
• clean pipette for transporting solutions.

The set will allow a person to understand what kind of blood he has. Everyone can analyze for himself. The wells on the tablet contain reagents for antigens (zoliclones -A, -B, -AB), as well as for the main antigen, which allows you to find out your Rh factor (tsoliclone anti-D).

Well number 5 contains the control reagent. It helps to prevent possible errors and inaccuracies, to correctly determine group membership and other important indicators. Despite the ease and availability of this procedure, the most proven method of research is still considered to be an appeal to a specialized laboratory or medical center. The probability of error in this case is relatively small.

As a rule, you will only find out your blood type and Rh factor only during health problems. And everyone should know such important information about themselves and their loved ones by heart. After all, you can improve your well-being by following nutritional recommendations, which are based on information about your blood type.

• Method of conglutination on Petri dishes;
• Express method;
• Gelatin express method.

• Do the analysis on an empty stomach (but you can drink water);
• The last meal should be more than 8 hours ago;
• Doctors do not recommend doing an analysis when taking any medications;
• Unhealthy food and alcohol should be avoided before the procedure;
• It is advisable to take an analysis, without preliminarily heavily loading the body.

• To donate blood, you need to feel good and have no contraindications from a doctor;
• Your age must be between 18 and 60 years old, weight over 50 kg;
• On the eve of donation, be sure to have dinner (but do not eat fatty, smoked, spicy and dairy foods, alcohol is contraindicated);
• Smoking is allowed before and after the procedure;
• Breakfast should be light, the planned day is not physically busy.

Determination of the Rh factor and blood type is mandatory not only for donors and patients. This is vital information for every person. It is possible that one day it will save your life.

When undergoing a medical examination, registering a woman for pregnancy, registering in a hospital, donating blood, one of the questions that must be asked to the patient concerns the blood type and Rh factor. This information is of great value in case of an urgent need for a blood transfusion, an emergency operation. How to find out the blood type and what to do with this information?

Blood types: classification

For simplicity and convenience, many countries use the AB0 system, according to which all people are divided into 4 large groups depending on the presence / absence of antigens and antibodies in the blood.

• Two types of antibodies (agglutinins in blood plasma) - α and β
• Two types of antigens (substances that simulate the production of antibodies) in erythrocytes - A and B

Accordingly, the following options are possible:

1. Group 0 (first group) - both types of antibodies are present in the blood, but there are no antigens. This blood type is the most common. It is believed that it is she who is the ancestor of all the others that appeared as a result of changes in the living conditions and nutrition of people.
2. Group A0 (second group). In the blood, respectively, antigen A and agglutinin β are present.
3. Group B0 (third group) - characterized by the presence of antigen B in the plasma, and α antibodies in erythrocytes.
4. Group AB (fourth group) is the opposite of the first, both antigens migrate in the blood, there are no antibodies. This group is the youngest, scientists attribute its appearance to the spread of mixed marriages, a kind of evolution of the circulatory system: the fourth group is the rarest, but people with such blood are universal recipients, they are suitable for blood transfusion of any of the four groups.

People with the first blood type are considered universal donors, it suits everyone else, while patients with blood 0 themselves accept only the blood of their own group for transfusion. Accordingly, the blood of the first and its own groups is suitable for the second and third groups.

In addition to the blood group, another important indicator is taken into account: the Rh factor.

If the D antigen is found on the surface of erythrocytes (red blood cells), then it is customary to speak of a positive Rh and designate it with the letter Rh +. About 85% of people on the globe are considered "positive". The remaining 15% of the D antigen is not detected, is called Rh-negative and is designated as Rh-.

Here is how blood groups are written with the Rh factor indicated:

• II (0) Rh+ / I (0) Rh –
• II (A0, AA) Rh+/ II (A0, AA) Rh-
• III (B0, BB) Rh+/ III (B0, BB) Rh-
• IV (AB) Rh+/ IV (AB) Rh-

Where can I find my blood group?

1. The easiest way to determine the blood group is an analysis at a clinic or medical center. The blood is mixed with standard, specially prepared sera and by agglutination, after 5 minutes the group is determined. Similarly, the Rh factor is determined using anti-Rh serum. The test takes little time, is highly accurate and allows in emergency cases to quickly give an answer about the patient's group affiliation.
2. Make your own rapid test at home.

Home test for Rh factor

The pharmacy sells kits for self-determination of the blood type. They include a test strip on which reagents are applied, a needle, a pipette and a circuit for determining the result.

A drop of blood from a finger is applied to the areas of the test strip and the result is evaluated after a certain time.

Before carrying out the determination, you need to make sure that the packaging is not damaged, the expiration date of the test has not expired. This method is convenient for determining the blood group in the elderly, debilitated, bedridden patients, and in young children.

The determination of the blood group in the laboratory is more reliable and, if possible, it is worth entrusting such a responsible matter to professionals.

Where is the blood type recorded?

After determination, data on the blood type and Rh factor are entered into the medical record. Men of military age, women liable for military service receive a mark on their military ID. A similar stamp can be put in the passport so that, if necessary, urgent assistance is provided immediately.

Methods for conducting a study of belonging to blood groups without taking tests

1. The blood type of a child can be determined by the parents. In some cases, a variant is possible, in some the answer will be unambiguous. In parents with the same Rh, the child inherits it with a probability of 100%. If the parents have a different Rh factor, then the chances of inheriting any of them are equal. In cases where an Rh-positive mother develops an Rh-negative fetus, an Rh-conflict is possible, which is fraught with miscarriage and miscarriages in the early stages. It is very important to take action from the doctor.

• The first group is monovariant: parents with blood group 0 can only have children with the same group. In other cases, options are possible. The first group may "appear" in parents with the second and third groups, but never with the fourth.

Since an exact answer can only be obtained for a child whose both parents have the first positive blood type, nevertheless, in all other cases, one cannot do without tests.

The combination of different blood types, especially when the mother is with the first group, can lead to the development of late preeclampsia and eclampsia, a woman should be under the supervision of a doctor, constantly monitor blood clotting, and if necessary, take blood thinners. In some cases, antigenic sera are indicated. In newborns, hemolytic jaundice is often observed.

According to blood groups, the character of a person is determined and special diets are made up:

• People with the first blood group are light and sociable, purposeful, emotional and trusting. In food, they prefer meat products, and in order to lose weight, they need to give up dairy foods;
• The second blood type "disposes" to daydreaming and solitude, suggests an analytical mindset and the ability to listen to the interlocutor. The diet of such people is dominated by plant foods, but meat should be reduced to a minimum;
• People with the third blood type are creative bohemia, originals and outrageous lovers. They love dairy products, but fatty meat, seafood, nuts are food alien to them;
• The fourth group “rewards” with an easy character, excellent intuition and independence. They are recommended seafood, green vegetables and fruits, rice; under the ban - red meat and offal, mushrooms, nuts, some fruits.

Determining the blood type by taste preferences, appearance or character traits is akin to fortune telling on coffee grounds. A medical test is not complicated, it is worth doing it once, fixing the results officially and not returning to this issue again

Method of determination Filtration of blood samples through a gel impregnated with monoclonal reagents - agglutination + gel filtration (cards, cross method). If necessary (detection of the A2 subtype), additional testing is carried out using specific reagents.

Material under study Whole blood (with EDTA)

Home visit available

Determines belonging to a certain blood group according to the ABO system.

Blood groups are genetically inherited traits that do not change during life under natural conditions. The blood group is a certain combination of surface antigens of erythrocytes (agglutinogens) of the ABO system.

The definition of group affiliation is widely used in clinical practice in the transfusion of blood and its components, in gynecology and obstetrics in the planning and management of pregnancy.

The AB0 blood group system is the main system that determines the compatibility and incompatibility of transfused blood, since its constituent antigens are the most immunogenic. A feature of the AB0 system is that in the plasma of non-immune people there are natural antibodies to the antigen that is absent on erythrocytes. The AB0 blood group system consists of two group erythrocyte agglutinogens (A and B) and two corresponding antibodies - plasma agglutinins alpha (anti-A) and beta (anti-B).

Various combinations of antigens and antibodies form 4 blood groups:

Group 0 (I) - group agglutinogens are absent on erythrocytes, agglutinins alpha and beta are present in plasma;

Group A (II) - erythrocytes contain only agglutinogen A, agglutinin beta is present in plasma;

Group B (III) - erythrocytes contain only agglutinogen B, plasma contains agglutinin alpha;

Group AB (IV) - antigens A and B are present on erythrocytes, the plasma does not contain agglutinins.

Determination of blood groups is carried out by identifying specific antigens and antibodies (double method or cross-reaction).

Blood incompatibility is observed if the erythrocytes of one blood carry agglutinogens (A or B), and the plasma of another blood contains the corresponding agglutinins (alpha or beta), and an agglutination reaction occurs. It is necessary to transfuse red blood cells, plasma and especially whole blood from a donor to a recipient strictly observing group compatibility. To avoid incompatibility between the blood of the donor and the recipient, it is necessary to accurately determine their blood groups by laboratory methods. It is best to transfuse blood, erythrocytes and plasma of the same group that is determined in the recipient. In an emergency, group 0 RBCs, but not whole blood!, can be transfused to recipients with other blood types; group A red blood cells can be transfused to recipients with blood types A and AB, and red blood cells from a group B donor can be transfused to recipients of blood groups B and AB.

Blood group compatibility cards (agglutination is indicated by a "+" sign)

Group agglutinogens are found in the stroma and membrane of erythrocytes. Antigens of the ABO system are detected not only on erythrocytes, but also on cells of other tissues or can even be dissolved in saliva and other body fluids. They develop in the early stages of intrauterine development, the newborn is already in significant quantities. The blood of newborns has age-related characteristics - characteristic group agglutinins may not yet be present in the plasma, which begin to be produced later (constantly detected after 10 months) and the determination of the blood group in newborns in this case is carried out only by the presence of antigens of the ABO system.

In addition to situations associated with the need for blood transfusion, determination of the blood group, Rh factor, and the presence of alloimmune anti-erythrocyte antibodies should be carried out at the time of planning or during pregnancy to identify the likelihood of an immunological conflict between mother and child, which can lead to hemolytic disease of the newborn.

Hemolytic disease of the newborn - hemolytic jaundice of newborns, caused by an immunological conflict between the mother and the fetus due to incompatibility for erythrocyte antigens. The disease is caused by incompatibility of the fetus and mother for D-rhesus or ABO antigens, less often there is incompatibility for other rhesus- (C, E, c, d, e) or M-, M-, Kell-, Duffy-, Kidd- antigens. Any of these antigens (more often D-Rhesus antigen), penetrating into the blood of a Rh-negative mother, causes the formation of specific antibodies in her body. The latter enter the fetal blood through the placenta, where they destroy the corresponding antigen-containing erythrocytes.

Predispose to the development of hemolytic disease of the newborn is a violation of the permeability of the placenta, repeated pregnancies and blood transfusions to a woman without taking into account the Rh factor, etc. With an early manifestation of the disease, an immunological conflict can cause premature birth or miscarriages. There are varieties (weak variants) of antigen A (to a greater extent) and less often of antigen B. As for antigen A, there are variants: strong A1 (more than 80%), weak A2 (less than 20%), and even weaker ones (A3, A4 , Ah - rarely). This theoretical concept is important for blood transfusion and can cause accidents when assigning an A2 (II) donor to group 0 (I) or an A2B (IV) donor to group B (III), since the weak form of the A antigen sometimes causes errors in the determination ABO blood groups. Correct detection of weak variants of antigen A may require repeated studies with specific reagents.

A decrease or complete absence of natural alpha and beta agglutinins is sometimes noted in immunodeficiency states:

neoplasms and blood diseases - Hodgkin's disease, multiple myeloma, chronic lymphatic leukemia;

congenital hypo- and agammaglobulinemia;

in young children and the elderly;

immunosuppressive therapy;

severe infections.

Difficulties in determining the blood group due to the suppression of the hemagglutination reaction also arise after the introduction of plasma substitutes, blood transfusion, transplantation, septicemia, etc.

Inheritance of blood groups. The following concepts underlie the patterns of inheritance of blood groups. In the ABO gene locus, three variants (alleles) are possible - 0, A and B, which are expressed in an autosomal codominant manner. This means that in individuals who have inherited genes A and B, the products of both of these genes are expressed, which leads to the formation of the AB (IV) phenotype. Phenotype A (II) can be in a person who inherited from parents two genes A or genes A and 0. Accordingly, the phenotype B (III) - when inheriting two genes B or B and 0. Phenotype 0 (I) manifests itself when inheriting two genes 0 Thus, if both parents have blood group II (genotypes AA or A0), one of their children may have the first group (genotype 00). If one of the parents has blood type A (II) with a possible genotype AA and A0, and the other B (III) with a possible genotype BB or B0 - children can have blood types 0 (I), A (II), B (III ) or AB (IV).

Determination of the blood group- this is an analysis by which a person's belonging to a group of people with certain immunogenetic characteristics of blood is revealed, which makes it possible to establish their compatibility with each other on this basis. The blood group is formed in a child during the period of prenatal development and remains unchanged throughout life.

Why is it important to know your blood type?

Determination of compatibility by blood type is necessary, first of all, for transfusion (blood transfusion). A large loss of blood is deadly. Since ancient times, attempts have been made to compensate for blood loss by infusing the blood of another person. But the first blood that comes across cannot be used. When mixing blood "blindly" in about half of the cases, agglutination occurs: red blood cells (erythrocytes) begin to stick together, forming clusters. Flakes arising from agglutination are visible in the test tube to the naked eye; it is clear that if this process happens inside the circulatory system, nothing good can be expected for a person.

At the beginning of the 20th century, it was established why agglutination occurs. On the surface of the membrane of an erythrocyte (red blood cell) there are special antigen proteins (they are called agglutinogens). They are called antigens because they can bind to other substances - antibodies. This connection is specific, that is, a given antigen can only be associated with a specific antibody. When we talk about blood groups, we use a system that is only interested in two antigens (in fact, there are many more of them that “ride” on red blood cells). For convenience, these antigens (agglutinogens) are designated by the first letters of the Latin alphabet - A and B. The antibodies corresponding to them (they are called agglutinins) are designated by the first letters of the Greek alphabet - α (alpha) and β (beta).

It is obvious that the antigen and the corresponding antibody cannot be in the blood at the same time, otherwise the reaction (agglutination) would take place. But other combinations are possible. It is they who determine which group our blood belongs to.

Blood types and their compatibility

In domestic medicine, groups are indicated by a number and are named accordingly: first, second, third, fourth. Abroad, this system is called AB0 and appropriate designations are used.

Group I(group 0) - the first (or zero). In people with blood of this group, both agglutinogens (A and B) are not on the erythrocyte membrane, but agglutinins α and β are present in the plasma.

Group II(A) - the second group. The blood of this group contains agglutinogen A and agglutinin β.

Group III(B) - the third group. Agglutinogen B is present on erythrocytes in blood, and agglutinin α is present in plasma.

Group IV(AB) - the fourth group. Both antigens are present on erythrocytes, but there are no antibodies in plasma.

Whole blood can be transfused only when the blood of both the donor and the recipient belongs to the same group. Red blood cells can also be used for transfusion (they are separated from the plasma), in which case only agglutinogens matter. Human erythrocytes of the first blood group can be transfused to everyone, since they cannot bring antigen and provoke agglutination. Therefore, a person with the first blood group is a universal donor.

Red blood cells of the second group can be transfused to people who already have agglutinogen A in their blood - that is, with the second and fourth groups. Accordingly, erythrocytes of the third group can be transfused to those who have agglutinogen B in their blood, these are the third and fourth groups.

A person with the fourth blood type is a universal recipient: he can be transfused with red blood cells from people with any blood type, while his blood can only be used for transfusion to people with the same blood type.

When is a blood typing done?

Indications for determining the blood group are:

• the need for a blood transfusion;
• preparation for operations. Any operation is a risk; under certain circumstances, it may be necessary to compensate for blood loss, and then doctors must know what kind of blood can be used for this;
• . In some cases, incompatibility of the blood types of the mother and child is possible. If there is a blood type conflict, a child may be born with hemolytic disease of the newborn (hemolytic jaundice). To determine the blood type of the child, immediately after birth, cord blood is taken for analysis. But the conflict by blood type can also be judged in the process of gestation - by the level of antibodies in the mother's blood. The risk of blood type incompatibility between mother and child is calculated based on the probable blood type of the child, which, in turn, depends on what blood type the mother and father have. Here, to assess this risk, it is necessary to take an analysis to determine the blood group during pregnancy.

When doctors need to know the blood type, the analysis is usually done again. This is done to completely eliminate the possibility of error as a result of using incorrect data. The doctor will not ask the patient's blood type, because he is responsible for his life and must be one hundred percent sure that the blood type is determined correctly.

But knowing your blood type (and the blood type of your children) is still useful. First, no one can be immune from emergencies. And secondly, there is a certain relationship between blood type and predisposition to various diseases.