Blood type of parents and child. Should they always match? Can children be born if the parents have different blood types? What type of blood will the child have?
Having learned about pregnancy, women strive to get as much as possible more information about your future baby. It is, of course, impossible to determine what character or eye color he will inherit. However, when referring to genetic laws, you can easily find out what blood type the child will have.
This indicator is directly related to the properties of the blood fluid of mom and dad. To understand how inheritance occurs, it is necessary to study the ABO system and other laws.
What groups exist
A blood type is nothing more than a feature of the structure of a protein. It does not undergo any changes, regardless of the circumstances. That is why this indicator is considered as a constant value.
Its discovery was carried out in the 19th century by the scientist Karl Landsteiner, thanks to whom the AVO system was developed. According to this theory, blood fluid is divided into four groups, which are now known to every person:
- I (0) - no antigens A and B;
- II (A) - antigen A is present;
- III (B) - B occurs;
- IV (AB) - both antigens exist at once.
The presented ABO system contributed complete change scientific opinions regarding the nature and composition of blood fluid. In addition, mistakes that were previously made during transfusion and were manifested by incompatibility of the patient’s and donor’s blood were no longer allowed.
There are three groups in the mn system: N, M and MN. If both parents have M or N, the child will have the same phenotype. The birth of children with MN can only occur if one parent has M and the other has N.
Rh factor and its meaning
This name is given to a protein antigen that is present on the surface of red blood cells. It was first discovered in 1919 in marmosets. A little later, the fact of its presence in people was confirmed.
The Rh factor consists of more than forty antigens. They are marked numerically and alphabetically. In most cases, antigens such as D, C and E are found.
According to statistics, in 85% of cases Europeans are diagnosed with positive Rh factor, and in 15 percent it is negative.
Mendel's laws
In his laws, Gregor Mendel clearly describes the pattern of inheritance of certain characteristics in a child from his parents. It is these principles that were taken as a strong basis for the creation of such a science as genetics. In addition, they must be considered first in order to calculate the blood type of the unborn baby.
Among the main principles according to Mendel are the following:
- if both parents have group 1, then the child will be born without the presence of antigens A and B;
- if the father and mother have 1 and 2, then the baby can inherit one of the presented groups; the same principle applies to the first and third;
- the parents have the fourth - the child develops any one except the first.
The child’s blood group cannot be predicted from the parents’ blood group in a situation where mom and dad are 2 and 3.
How does a child inherit from parents?
All human genotypes are designated according to the following principle:
- the first group is 00, that is, the baby’s first zero is transmitted from his mother, the other from his father;
- the second - AA or 0A;
- the third is B0 or BB, that is, in this case the transfer from the parent will be B or 0 indicator;
- fourth - AB.
A child's inheritance of a blood type from its parents occurs according to generally accepted genetic laws. As a rule, parental genes are passed on to the baby. They contain all the necessary information, for example, the Rh factor, the presence or absence of agglutinogens.
How does Rh factor inheritance occur?
This indicator is also determined based on the presence of protein, which is usually present on the surface of the erythrocyte composition. If the red blood cells contain it, then the blood will be Rh positive. In the case where the protein is absent, a negative Rh factor is noted.
According to statistics, the ratio of positive and negative indicators will be 85 and 15%, respectively.
Inheritance of the Rh factor is carried out according to a dominant trait. If two parents do not have the antigen that determines this indicator, then the child will also have a negative value. If one parent is Rh positive and the other is Rh negative, then the probability that the child can act as a carrier of the antigen is 50%.
If the mother and father have factors with a “+” sign, then in 75 percent of cases the baby inherits Rh positive. It is also worth noting that in this case there is a high probability that the child will receive the genes of a close relative who has a negative value for this indicator.
For more accurate understanding How the Rh factor is inherited, you can consider in detail the data given in the table below.
How to find out the blood type of your unborn baby
To determine whose blood type the child inherits, experts have developed a special table that allows each future parent to make predictions independently.
Upon careful study of the tabular results, the following interpretation is possible:
- the blood of parents and children will be the same only if mom and dad have the first group;
- if there is a second group in both parents, the child will inherit 1 or 2;
- when one parent has the first, the baby cannot be born with the fourth;
- if mom or dad has the third group, then the probability that the child will inherit the same is the same as in the previous described cases.
If the parents have group 4, the baby will never have the first.
Could there be incompatibility?
In the second half of the 20th century, after the definition of group 4 and the recognition of Rh factors, a theory describing compatibility was also developed. At the beginning this concept used exclusively for transfusion.
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The blood fluid administered must not only match the group, but also have the same Rh factor. If this is not followed, conflict arises, which ultimately leads to fatal outcome. Such consequences are explained by the fact that when incompatible blood enters, red blood cells are destroyed, which leads to a cessation of oxygen supply.
Scientists have proven that the first group is considered the only universal group. It can be transfused to any person, regardless of blood group and rhesus. The fourth is also used in any situation, but with the condition that the patient will only have a positive Rh factor.
When pregnancy occurs, it is also possible that there may be a blood conflict between the child and the woman. Such situations are predicted in two cases:
- The woman's blood is negative, and the father's is positive. Most likely, the baby will also have a value with a “+” sign. This means that when it enters the mother’s body, her blood fluid will begin to produce antibodies.
- If expectant mother the first group, and for a man any other except 1. In this case, if the child does not also inherit the 1st group, a blood conflict cannot be ruled out.
If the first situation arises, everything may not end with the most favorable consequences. When inherited by a positive Rh fetus the immune system A pregnant woman will perceive the baby's red blood cells as foreign and strive to destroy them.
As a result, when the child’s body loses red blood cells, it will produce new ones, which puts a very noticeable load on the liver and spleen. Happens over time oxygen starvation, the brain is damaged, and fetal death is also possible.
If this is your first pregnancy, then Rh conflict can be avoided. However, with each subsequent one the risks increase significantly. In such a situation, a woman should be constantly monitored by a specialist. She will also need to have blood tests done quite often for antibodies.
Immediately after the baby is born, his blood fluid group and its Rh factor are determined. At positive value The mother is given anti-Rhesus immunoglobulin.
Such actions help prevent adverse consequences when conceiving a second and subsequent children.
The second option does not pose a threat to the baby's life. In addition, it is diagnosed extremely rarely and does not have a complex process. The exception is hemolytic disease. If you suspect the development of this pathology, you will need to undergo regular tests.. In this case, for the birth to be successful, the most favorable period is considered to be 35-37 weeks.
Most experts argue that with a higher value of father's blood relative to mother's, the likelihood of having a healthy and strong child almost equals 100 percent.
Conflicts due to incompatibility in the blood group of parents are not such a rare occurrence, but also not as dangerous as incompatibility with the Rh factor.
If you conduct a timely examination, regularly visit a gynecologist and do not ignore the instructions of the attending physician, this will increase the likelihood of a successful conception, pregnancy and birth of a baby.
Inheritance of blood groups is not such a complicated science. Knowing all the subtleties and nuances, you can find out what group and Rhesus he will have even before the birth of the child.
When planning a pregnancy, a married couple needs to undergo certain examinations. At the same time, it is important to find out the compatibility of blood groups for conceiving a child, because this will avoid many complications during pregnancy and ensure the healthy development of the baby.
You can take a special test to determine your parents’ blood group and Rh factor in any clinic. The results will help the gynecologist make the right prescriptions during pregnancy to minimize possible influence different Rh factors of parents for the baby.
The blood group division system is based on specific sets of proteins A and B. Genetics define them as alpha and beta agglutinogens.
Group 1 – no alpha and beta agglutinogens
Group 2 – alpha agglutinogens are present
Group 3 - beta agglutinogens are present
Group 4 – alpha and beta agglutinogens are present
There is an opinion that women with the first group do not experience problems with pregnancy and they give birth healthy babies. Such people are the best donors, because this blood group has excellent compatibility with all others (in the case of a Rh match). It is believed that these people prefer to eat meat products. There is an opinion that people with blood type II prefer vegetable and fruit dishes. And on the third, they prefer flour.
Myths about compatibility
There is a blood group compatibility table for conceiving a child floating around the Internet.
Allegedly, women with the first blood group are incompatible with men of the second, third and fourth. Women with the second - with men who have the third or fourth group, etc. There is another opinion: if the spouses have the same blood type, then conception is unlikely, or in this case weak children are born.
Obstetricians and gynecologists say: all this is complete nonsense. Such tables have nothing to do with medicine; they are completely invented by unscrupulous “healers” or illiterate authors of articles. The blood of the parents does not affect the conception of the child in any way!
To eliminate any last doubts, conduct a short survey of your own parents, relatives or friends who have children. You will see that babies are born to couples with a very different combination of blood groups: 1 and 2, 2 and 4, 1 and 4, and so on.
In some rare cases, a woman cannot become pregnant due to so-called immunological incompatibility. Seminal fluid men contains certain components that are rejected by the woman’s immune system. The partner develops a kind of “allergy” to the man’s sperm. In some articles, this phenomenon is associated specifically with blood type. But blood has nothing to do with it; this phenomenon is of a completely different order. By the way, such incompatibility can be successfully treated.
Rhesus conflict
When parents have the same Rh factor, we can say with confidence that they will have excellent compatibility. Determining compatibility by Rh factor is an important component when planning pregnancy. Possessing necessary information and, accordingly, getting the correct medical treatment, such couples will be able to significantly reduce the risk of spontaneous abortions and avoid problems with the health of the unborn baby.
If the mother has a Rhesus sign with a plus sign, and the father has a Rhesus sign with a minus sign, then this will not affect conception in any way. Moreover, geneticists claim that in most cases the baby is also born “positive”. In this case, we can say that the parents are compatible to conceive a child.
If the situation is the opposite (mother is a minus, father is a plus), then this can lead to certain problems. If a child inherits Rh negative from his mother, then everything will be fine. If the fetus has +, and this is not the first pregnancy, then a conflict is possible.
See table.
The conflict will not affect conception, but it may interfere with the natural development of the fetus or the pregnancy may end in spontaneous abortion.
The female body perceives the baby as something foreign that needs to be gotten rid of. The active confrontation between the mother's particles and the protein in the baby's cells leads to a conflict that significantly affects the condition of the fetus. And pregnancy is accompanied by such unpleasant complications as severe toxicosis, general weakness and severe fatigue.
Pregnancy and Rhesus
Even if a woman is Rh negative and a man is Rh positive, conflict usually does not occur during the first conception, since the mother’s body has not yet developed antibodies to foreign proteins. Therefore, it is especially dangerous for women with Rh negative to have an abortion if she is pregnant for the first time.
But subsequent pregnancy due to the effects of antibodies, as a rule, causes certain difficulties. The following maternal diseases provoke an increase in the number of antigens:
- Preeclampsia;
- Diabetes;
- Increased uterine tone.
The result of such a conflict can be anemia, jaundice, and dropsy in the baby. However, this does not mean that such married couples have no chance of giving birth. If you follow all the recommendations of the attending physician, a healthy child will be born.
- Find out the baby’s Rh factor using a chorionic villus biopsy;
- Periodically destroy antibodies by administering immunoglobulin;
- If necessary, perform a puncture of the fetal umbilical cord;
- Prescription of anti-allergy drugs and vitamin complexes;
- If a danger to the life of the mother or child is predicted, induce labor.
The best way out in this situation would be to register with a gynecologist long before planning a pregnancy if you want a second child. In this case, the woman will be prescribed anti-Rhesus immunoglobulin, which will significantly reduce the risk of possible complications.
What group will the child have?
Parents are also interested in what group and Rhesus their baby will have. Will they inherit the blood characteristics of mom or dad or will their indicators be different? Geneticists say that children inherit blood parameters in the same way as other characteristics.
If mom and dad are the owners of the first blood group, then their baby will also not have the antigen in the blood;
Parents with the first and second groups will pass on their groups to their offspring;
If the spouses are owners of the fourth group, then their child can be born with any indicator except the first;
The presence of parents of groups 2 and 3 makes it possible for a baby to be born with any of the four possible groups.
As for the Rh factor, everything is much simpler here. The presence of negative indicators in parents indicates that the child will be born with the same sign. If mom and dad have different Rhesus values, then the baby can have both positive and negative Rhesus.
Competently: an obstetrician-gynecologist answers questions
Our consultant is obstetrician-gynecologist Elena Artemyeva.
- I have 1 positive group blood, and the spouse has 1 negative. Is this bad for our unborn child?
- No. This difference will not have any effect on either conception or pregnancy.
“Both my husband and I have the third group, Rh positive. I heard that this is bad for conception.
— Blood type does not affect conception in any way.
- I can't get pregnant. Could this be due to the fact that my husband and I have the same blood type (2) and the same Rh factor (+).
- No, he can not. Look for the reason in the state reproductive health, you need to get examined.
- If I have 1 negative and my husband has the same, is this bad for the unborn child?
- No, in your case there will be no Rh conflict, since the child will have a negative Rh factor.
— I am Rh negative, my husband is positive. The first child was born healthy. During the second pregnancy, doctors did not detect the conflict in time, and the child died. What should I do now to ensure that my third pregnancy goes well?
— You need to prepare for such a pregnancy in advance. One option is to “cleanse” the blood of existing antibodies (for example, using plasmapheresis) so that the risk is minimal. During pregnancy, antibodies to the Rh factor should be monitored monthly. As soon as signs of sensitization appear, plasmapheresis is performed.
Another option is to go eco. In this case, Rh-negative embryos are identified and implanted.
- I have negative blood, my husband’s is positive. This is my first pregnancy and is going well. Is it necessary to give immunoglobulin after childbirth in order to next pregnancy there was no conflict?
- Yes, this must be done in the first 72 hours after birth.
From time immemorial and until the beginning of the 20th century, practically nothing was known about the birth of a child and his heredity. The situation changed at the turn of the century, when the Austrian scientist Karl Leinsteiner, studying red blood cells, determined that the composition of blood in people differs and depends on genetic processes.
This discovery became a new milestone in medicine, explaining why, during a transfusion, the donor's working material did not help the patient.
Nowadays, thanks to the research of great scientists, it is possible to learn a lot about a child long before his birth. To avoid hereditary or mutational diseases, it is recommended to take a blood test for the compatibility of future parents even before going to the registry office. Owning necessary information, you will know how to act in the future and will be able to provide your baby with a fulfilling future.
For example, Rh conflict can occur during conception in an Rh-negative woman and an Rh-positive man.
What determines a child's blood type?
The generally accepted law divides all people into 4 blood groups, which in turn depend on the ABO system. Their difference is in the indicator of red blood cells (erythrocytes).ABOUT- the absence of agglutinogens in a person indicates that his blood belongs to the first group.
A- in an active position belongs to the second group.
IN- can only be in the active position with the third group.
A and B– erythrocyte antigens in joint action indicate rare case the presence of a person of the fourth blood group.
Depending on the combination of parental antigens and their Rh factor, the child’s blood type is determined. Accurate data can only be obtained in laboratory conditions.
Inheritance of the Rh factor?
Rhesus, Rh- one of the 29 blood group systems has a positive or negative status. In the absence of this indicator, that is, a negative position, a Rh conflict with a partner and a corresponding danger to the fetus is possible.When a child with a negative Rh factor is born in a family of parents with a positive Rh factor, great surprise arises, and even sometimes mistrust in the form of reproaches and doubts about the honesty of the spouse. But there is a simple explanation for this problem.
Rh factor is an antigen (protein) located on the surface of erythrocytes, red blood cells. About 85% of people have this very Rh factor, that is, they are Rh positive. The remaining 15% who do not have it are Rh negative. These factors are denoted by the letters Rh, positive with a plus sign, negative with a minus sign. To study Rh, usually take one pair of genes.
DD or Dd is a positive Rh factor, and is a dominant trait, dd is negative, recessive.
If a couple has heterozygous Rhesus (Dd), then in 75% of cases their children will also have positive Rhesus, and 25% negative.
If parents have Dd x Dd factors, then their children will have DD, Dd, dd. Heterozygosity appears in a child as a result of the conflict of the mother’s Rh-negative factor, so to speak, and can be transmitted to many generations.
How to determine a child's blood type based on his parents?
Each child will inherit two blood group genes from their parents: the first belongs to the mother (A, B, or 0), the second to the father (A, B, or 0).These indicators are combined with each other as follows:
(table No. 1) 
- Parents with blood type I (the most common) will produce offspring without red blood cell antigens (O).
If the husband has group 1, the wife has group 2 and vice versa, then the children will have similar positions. I(O) and III(B) are combined in the same way.
The fourth group in one of the parents can lead to any indicators except the 1st group. And the partner will not be able to influence this in any way.
The combination of groups II(A) and III(B) gives unpredictable results. The baby can be born with any of 4 types of groups.
An exception is the phenotype with A and B antigens in a passive form. They simply do not manifest themselves in any way, they are extremely rare and only in Asian countries, due to which the case is called the “Bombay phenomenon”.
(table No. 2) 
(table No. 3) 
Incompatibility of mother and child by blood type
It is known that pregnant women with a negative Rh factor in their blood should be under special supervision, since when the fetus develops a positive Rh factor, a Rh conflict may occur, which is fraught with consequences.But there may also be incompatibility in blood groups. If the blood of the mother and the fetus contain different antigens, the mother's blood can produce antibodies in relation to the child's. Incompatibility is possible with group I or III in the mother and group II in the fetus; Group I or II in the mother and group III in the fetus; any blood group in the mother, when the fetus has group IV. If the mother and father different groups blood, then the presence of group antibodies in the pregnant woman and the fetus must be checked. The exception is a combination in which the father has the first blood group.
Attention!
It is advisable for every person to know their blood type. Anyone can experience a situation that requires an urgent blood transfusion. And it is knowledge of one’s group that can save a human life: one’s own or someone else’s. The fact is that a person can only be infused with blood that is native to his blood group, that is, only IV (AB) is infused into IV (AB), and only II (A0) into II (A0).But it happens that there is no time to find out or determine the blood type of one of the participants in the transfusion, then it is possible to infuse a minimum portion of blood of the first group with negative Rh - this universal blood, compatible with all types of antigens.
By the way, the first group together with the second are the most common in the world. And the rarest of all is the fourth group, whose carriers are only 3-5% of all people.
It happens that a child’s blood type does not match the parent’s, which raises a lot of questions. This question was discovered by a scientist from Australia, K. Landsteiner. By studying the behavior of red blood cells in different people, he derived three AOB systems. In some, red blood cells are evenly distributed, in others they stick together. Genes with information about the presence or absence of agglutinogens are inherited. This is how I (OO), II (AA or AO) and III (BB or VO) appeared, and the fourth (AB) was discovered a little later. In all compounds, the first letter means information about the presence or absence of an agglutinogen that the child will receive from the mother, the second - from the father.
For example:
- with I (OO), antigens A and B are absent, therefore, if the father and mother have the first group, then the child will inherit it;
- one parent is with the first, the other with the second, then the offspring can be born with I or II;
- if the mother has II, and the father III, or vice versa, then the children will take any of the four;
- I and III – give only the first and third;
- if the parents have the fourth, then the baby will be born with any but the first, since both agglutinogens are present in the hereditary set. Thus, the child’s blood type may not coincide with the parent’s.
There are exceptions to all rules
Scientists have identified the fact of exclusion when both parents have IV (AB), and the child is born with I (OO). There are agglutinogens in the blood, but for some reason they do not appear; this phenomenon is still being studied. This fact is quite rare, and even rarer among the Caucasian race. " Bombay phenomenon“, as it is called, it appears more often in dark-skinned people, among Indians.
Blood transfusions can affect the genetic makeup, making it difficult to determine the baby's exact group. The agglutinogenic composition can be changed by many factors; it is quite difficult to determine this. Therefore, the blood group of parents and children cannot be called 100% interconnected and, moreover, paternity cannot be established using it. Initially, studies on the presence of heredity were not carried out, and are not being conducted now.
The most common are I and II, they are owned by almost 40% of the world's population. The rarest is IV, which only 3–5% of people have.
In addition to the group, blood is divided into Rh factor - positive and negative. Which also has its own rules and exceptions. A person with group I and a negative Rh factor is considered a universal donor. The most commonly required IV transfusion in the world is Rh positive.
Group blood baby– a topic that worries many. Numerous oddities and even tragedies are associated with it. Assessing what blood type your child may have is important, since there is a possibility of a blood type conflict between the mother and the child. How to determine this?
You will need
- - paper;
- - pen;
Instructions
The blood type is determined by the types of antigens (agglutinogens) found on the surface of red blood cells. There are 2 main types of antigens - A and B. Accordingly, on red blood cells there can be either antigens of only type A - the second, or only type B - the third blood, or both A and B - the fourth group, or they may not be there - the first group.
Blood type is inherited according to the principle of complete and incomplete dominance and is determined by which blood group genes a person has. There are three types of blood group genes: A – determines the presence of type A antigen; B – determines the presence of type B antigen; 0 – determines the absence of antigens. Each person has 2 such genes in their genome. In this case, the following combinations can occur:
00. Blood group 1, no antigens on red blood cells.
AA or A0. Only type A antigens are present, blood group is second.
BB or B0. Type B antigens are present, the third blood group.
AB. There are antigens of both types, blood group is fourth.
In order to assess what blood type yours may have, it is important to know that 1 blood group gene is passed on from each parent. In this case, 4 arises possible combinations these genes. The easiest way to view this is in the form of a table, in which the top row contains the possible genes of one of the parents, and the left column contains the genes of the second parent. As from the table, which describes the option for a couple with the fourth and first blood groups, it is impossible to unambiguously predict which group it will be.
Make a table like this for your couple. Please note that if one of you has a second or third blood group, then you need to consider several options for gene combinations. B are given possible groups blood depending on the genotype of the parents, the blood type is indicated in brackets.
note
If there is a possibility of a conflict between mother and fetus regarding blood type, then after birth the newborn’s blood is immediately taken for analysis. If a conflict is detected, treatment may be needed.
Sources:
- how to determine the blood type of an unborn child in 2018
Know your group blood every person is obliged. Life is unpredictable and you may find yourself in a critical situation. Sometimes his life and health depend on how knowledgeable a person is.
Instructions
Find out the groups blood and Rh factors, group blood which you are going to calculate. Officially there are four groups blood. I (0): – in erythrocytes such blood there are no agglutinogens, but there are α and β. Group II (A) is its agglutinogen A, and its plasma contains agglutinin β. Group III (B) contains agglutinogen B in erythrocytes and agglutinin α in plasma. Red blood cells last group- IV (AB) contain agglutinogens of the species in erythrocytes, but they are not present in plasma at all.
Write down all the possible variations that could result from mixing groups. blood parents. A child receives only one gene from his father and mother. There are no options for the first and fourth groups, since in the first case there are no agglutinogens in erythrocytes, and in the second - in plasma. Combinations that are formed with the participation of the third and second groups blood and will become possible.
Write down all the variants of mixing Rh factors and determine the percentage probability of one or another variant.
There are patterns in the inheritance of genes. For example, if mom and dad have the same blood type - first, then their child will have exactly the same group. In addition, the presence of at least one of their parents of the first group automatically excludes the possibility of the child inheriting the fourth group, regardless of what group number the second parent has. And vice versa: if at least one parent has the fourth blood group, the birth of a child with the first group is excluded. The most a large number of options - for a child with parents who have the second and third blood groups. In this case, calculations do not make any sense, since a child can be born with any blood type and all options are equally probable.
Sources:
- how to figure out who I am by blood
Group blood is the most important part human life which everyone should know from birth. That is why future parents are worried and want to know for sure what she will be like.
Instructions
Often parents worry too much about the unborn. It is explainable. Yes, sometimes these concerns go beyond decency, but sometimes they are justified. Namely, most parents want to know with one hundred percent certainty group his . Firstly, the easiest way is to go to the hospital. U and father baby will take . Then they will tell you what groups they have. blood and what are the chances baby get the same one group.
Secondly, everyone has long known that the father has the same group blood. This similarity is confirmed in seventy to eighty percent of cases. Therefore, all dad needs to do is visit the hospital and get tested blood. But still, the remaining twenty to thirty percent of children do not receive the same inheritance group blood, like my own dad, and in connection with intrauterine diseases pathological changes that cause changes blood, have a completely different group.
In a simplified diagram, human genotypes various groups blood are written this way: - first group blood– 00. One of them is transmitted from mom, the other from dad. Consequently, the child also inherits the first group blood;- if you and your spouse have a second group blood AA or A0, then there will be blood of the first or second group (A or 0); - parents with the third group BB or B0 will expect a baby with the first or third group; - if mom and dad have the fourth group, then their son or daughter will have either a second, or a third, or a fourth group.
Use the table to determine the probability of a child inheriting a particular group blood. For example: if one of the parents has a fourth group blood, and the other has the first one, then the child will receive either the third or the second group. In such a family group blood the crumbs will never coincide with the parent.
remember, that group blood, calculated using special tables and diagrams, is not considered final. Get accurate information regarding the group blood and the Rh factor of your baby you can only in the laboratory. The group is determined by analyzing the venous blood.
Video on the topic
Sources:
- What blood type will the child have? (blood group and Rh factor calculator)
- How are blood types transmitted?
The existence of four blood types was proven by scientists at the beginning of the twentieth century. Studies have shown that the child's blood type will depend on the blood type of the parents, that is, it is inherited genetically.
What blood types exist?
As a result of research by Austrian scientists Karl Landsteiner and his students A. Sturli and A. Von Decastello, a blood classification system called “AB0” was created, which is still used today. According to this system, there are four blood groups:
I (0) - it is characterized by the absence in the blood special substances- antigens A and B;
II (A) - it contains antigens A;
III (AB) - characterized by the presence of type B antigens;
IV (AB) - there are antigens A and B in the blood.
This discovery helped eliminate losses during blood transfusions, since due to different characteristics, the donor's blood could cause harm to the patient's body.
What blood type will the child have?
In further studies, scientists have proven that the principles of obtaining a child’s blood type and other genetic characteristics will be identical. According to Mendel's laws, formulated back in the second half of the nineteenth century, parents with the first blood group produce children without antigens A and B (that is, having the first blood group). Parents with the second blood group have children with the first or second blood group. Spouses with the third blood group have children with the first or third blood group.
Parents with the first or second, or first and third blood groups give birth to children with one of these groups. If one of the spouses has the fourth group, the child cannot have the first blood group. If one of the spouses has the first blood group, they cannot have a child with the fourth blood group. Spouses with the second and third groups have children with any blood type.
Principles of inheritance of the Rh blood factor
The Rh factor is an antigen (protein) that is found on the surface of red blood cells. It is present in the blood of approximately 85% of people, meaning they are Rh positive. In the absence of this antigen they speak of Rh-negative blood. These factors are denoted by the letters Rh: negative with a minus sign, positive with a plus sign.
If both parents are Rh negative, they can only have a child with Rh negative blood.
A positive Rh factor is a dominant trait, and a negative one is a recessive trait. If both parents have both traits in their genotype, they will be Rh positive. However, in this case, there is a probability (25%) that the child in this case will be Rh negative. That is, if both parents or one of them has a positive Rh factor, they can have a child with both Rh positive and Rh negative blood.
Using a special blood test, it is possible to determine a person’s blood group and his Rh factor, which are a completely genetic predisposition. There are cases when there is a conflict of Rh factors. Therefore, it is very important to identify this process as early as possible and take certain measures.
Red blood cells in the blood have on their surface a certain amount of proteins called antigens, which in turn determine all hereditary characteristics.
When the human immune system suddenly detects some type of protein in the blood that is uncharacteristic for it, the process of producing antibodies is launched that stick to these foreign proteins. This process characterizes the natural protective function the body's immune system and its functioning.
Rh factor
Rh factor is a protein that may or may not be present on the surface of red blood cells. If it is present, the person is positive; if this protein is absent, the person is rhesus positive.
This trait, just like , is hereditary in nature and is determined by genetic predisposition. Highlight dominant gene R, which determines the inheritance of positive . The recessive gene is the r gene, the presence of which is characteristic of people with a negative Rh factor.
When both parents have a dominant RR gene or one of the parents is its carrier, unborn child will only have a positive Rh factor.
If the parents have a dominant and recessive Rr gene, the child can have both positive and negative Rh factor. The ratio is 75% to 25%.
If parents have different Rh factors (negative and positive), the probability of inheritance is 50% to 50%. Parents with negative Rh factors are 100% likely to have a child with the same Rh factor.
It is very important to consider the value of this indicator in the case of blood transfusion. Because when different Rh factors are combined, agglutination of positive red blood cells occurs - the process of gluing and precipitation of red blood cells carrying antigens.
Rhesus conflict
A condition in which the red blood cells of a pregnant woman, which have a negative Rh factor, secrete antibodies in relation to the Rh positive red blood cells of the fetus is called Rh conflict.
In order for such a situation to form, mixing of the blood of the mother and the fetus is necessary. If the pregnancy is progressing normally, this can only happen at the time of birth itself. Therefore, the possibility increases during the second and subsequent pregnancies.
There are cases of the development of some pathology while carrying a child, and then a Rhesus conflict can occur long before the moment of birth. In this case, consultation with a specialist and a thorough examination are required, after which it will be known further actions.
Instructions
There are 4 known blood groups. Red blood cells of the first blood group do not contain agglutinogens and this group is designated (0), i.e. zero. In people of the first blood group, agglutinins alpha and beta are present in the plasma, but the genetic set is determined by the agglutinogen, and in these people it is homozygous recessive, i.e. 00.
With the second blood group, the red blood cells contain agglutinogen A and the blood group is designated (A). But since the gene that determines blood type is inherited in a dominant-recessive manner, some people have the genetic homozygous AA set, while others are heterozygous and have the A0 set.
In a person with the third blood group, the erythrocytes necessarily contain an agglutinogen with a dominant B, and the group is designated (B), in cases of a homozygous set - the BB gene, and in cases of a heterozygous set - B0.
But in cases of genetic fusion of the first and fourth blood groups, the child will not inherit the group from either the father or the mother, but will belong to the second or third. This fact can be explained by the formula: AB + 00 = A0 or B0.
A child from parents with the second and third blood groups can have absolutely any group, it all depends on whether the parents are homozygous or not. When two homozygous sets are merged, the fourth blood group will definitely be obtained, i.e. AA+BB=AB. If one of the parents is homozygous with the first group, and the other is heterozygous and has the second group, the children will inherit any group except the first and third. When a homozygous father merges with the third group and a heterozygous mother with the second group, the baby will receive the fourth group or the third.
Parents with the fourth and homozygous third blood group more often pass on the third group, sometimes the fourth, to their generation. But in cases of heterozygous recruitment of the third group (B0) in one of the parents, the baby may also develop a second group, but more often it is still the third or fourth.
If both parents have the fourth blood group, their children may have different combinations of genes A and B, and any blood group will appear except the first.
Video on the topic
Currently, about 30 blood group systems are known, but one of the most significant is the ABO system, according to which four blood groups are distinguished. The second most important is the Rhesus system - blood is divided into 2 groups. You can read more about these systems in the article “Blood type and Rh factor”.
What blood type will the child have?
The blood type of the unborn child is strictly certain dependence from the blood types of the parents. According to the same principles of inheritance, a child receives his own blood type, eye color, skin color, and hair color. Genetic inheritance Blood type is strictly natural. But this does not mean that if both parents, for example, have the second blood group, then their children will only have the second.
It turned out that if parents have the second (II) and third (III) blood group, then their children can equally inherit any blood group. And vice versa, if mom and dad have the first (I) and fourth (IV), then the children will inherit a blood group different from their parents - second (II) or third (III). Also, the first group (I) is excluded if one of the parents has the fourth blood group AB (IV).
Blood type AB (IV) is quite rare in all parts of the world, regardless of nationality and race. It cannot be inherited, but is formed in the fetus under the influence of genes received from the parents - A and B.
Blood groups. Table
In addition to the simple interest “What blood type will the unborn child have?” There is another good reason to know what blood type your baby might have. During pregnancy, not only Rh conflict can occur, but in some cases, blood group conflict as well.
If the mother has the first blood group (I), and the child has any other, she can produce antibodies against it. In this case, it is necessary to check the presence of group antibodies in women with the first blood group, since in their presence it is possible to develop hemolytic disease newborn by blood type. However, a severe form of hemolytic disease of the newborn is rare, occurring only in isolated cases.
The blood of a certain number of people may contain a protein called the Rh factor (Rh). According to the Rh factor, all people can be divided into Rh-positive Rh(+) and Rh-negative Rh(-). Inheritance of the Rh factor occurs independently of the inheritance of blood type.
If a pregnant woman has Rh(-), and her husband has Rh(+), then in half the cases the planned child will have a positive Rh factor (Rh+). Rh conflict occurs during pregnancy of a woman with Rh negative, if the blood of the fetus is Rh positive.
It is possible to say exactly which Rh factor the child will inherit only in one case: if both parents have negative Rh status. All children of such a couple will have an Rh negative factor. In all other cases, the Rh factor can be anything.
When red blood cells from a Rh-positive fetus enter the blood of a Rh-negative mother, they are perceived by her immune system as foreign. The body begins to produce antibodies to destroy the baby's red blood cells. Since the fetus's red blood cells are continuously destroyed, its liver and spleen try to speed up the production of new ones, thereby increasing in size. As a result, they cannot cope, severe oxygen starvation occurs, which causes even more pathologies. In the most severe cases this can lead to fetal death.
At the antenatal clinic, a pregnant woman must be checked for the Rh factor. If it is negative, it is necessary to determine the father's Rh status. If there is a risk of Rh conflict (if the father has Rh(+)), the woman’s blood is repeatedly tested for the presence of antibodies to fetal red blood cells and their number.
During the first pregnancy, the immune system of the expectant mother only “gets acquainted with strangers” (Rh+ red blood cells), few antibodies are produced and a conflict may not arise. However, “memory cells” remain in the woman’s body, which, during subsequent pregnancies, quickly “organize” the rapid and powerful production of antibodies against the Rh factor. Consequently, the risk of fetal damage increases with each subsequent pregnancy.
