Determining a child's blood type based on his parents. Determining the Rh factor of a child using maternal blood. Determination of kinship by Rhesus

“Can a child have a different blood type?” – parents often ask. Let's deal with this in order.

Already in the nineteenth century, people knew about the existence of four groups. Scientists mixed different biomaterials and noted that the cells stuck together and formed clots. This indicated that the liquids that were mixed were somehow different from each other.

The birth of a baby is the main event in everyone’s life. married couple

Today people use the AB0 classification. Based on it, 4 types of blood are distinguished. It all depends on availability and combination certain substances(antigens and antibodies) in it:

• the first group does not contain antigens, so it is encrypted with the number 0;
• if protein A is present in the cells, this is the second;
• a third have B agglutinogen;
• and when agglutinogens A and B are combined, they speak of the fourth group.

The question often arises: can a child’s blood type differ from the parents’ blood? Yes, maybe we will consider this issue below.

In addition to antigens A and B, all people have a special protein D in their plasma and red blood cells; depending on its presence or absence, blood is divided into two categories. If this protein is present, then the person is Rh positive (Rh+); if it is not, the person is Rh negative (Rh-). This indicator does not affect health in any way.

At conception, the DNA of the parents is combined, so the fetus receives certain characteristics, some from the mother, others from the father. Depending on which of the genes encoding a particular trait is dominant, the child exhibits certain traits. Therefore, the child's blood type often does not match the blood type of the parents.

When conception occurs, information about the composition of the internal environment of the parents’ body is transmitted to the fetus. He receives one of two genes from his mom and dad, which are then combined in a certain way. The child develops its own set of antigens.

Sometimes the blood composition of children and parents is the same. But there remains a high percentage of manifestations of other combinations, so the set of proteins on red blood cells will be different. The baby will inherit the same protein composition as its parents if they have the same set of antigens. But even such couples have children with a different combination of proteins, when the child’s blood type does not match the parents.

Possible blood combinations are calculated using special tables and diagrams. But this indicator can be accurately determined only after the birth of the child, when the doctor does a special analysis. During fertilization, the fetus receives a set of genes consisting of antigens from both parents.

Each group is determined by a combination of antigens, there are two types of them, therefore both mother and father have the following proteins:

• the first group does not have them, so it is designated by the numbers 00 (without antigens);
• if the cells have protein A, this is the second group;
• people of the third group are carriers of the B antigen;
• the fourth is AB, it combines both antigens.

To find out whether a child may have a different blood type than his parents, and what percentage of the combination of a particular set of proteins is, it is worth remembering what we were taught at school in biology lessons.

What did Mendel say about inheritance?

The scientist studied in detail the transmission of traits from parents to offspring. Based on research, he formulated the laws of genetics, in which he explained how traits appear in descendants. The laws he formulated are able to explain whether a child can have a blood type different from his parents.

The fetus receives one gene each from its mother and father, so it has the hereditary information of both parents. If it is the same, then it also manifests itself in the child. If different, then the trait that is dominant appears, and the second one is simply present - recessive. But it is capable of manifesting itself in the next generation.

By studying the mechanism of inheritance of the composition of red blood cells and plasma, scientists found that genes A and B are dominant, and gene 0 is recessive. Based on this, if A and B proteins are combined, they suppress the recessive gene, and agglutinogens A and B will be present in the child’s plasma, therefore, his group will be defined as the fourth (BA, AB).

Blood group combination

A child's blood type is inherited from his parents, but does it have to match? The answer is clear - no. It all depends on whether the parent has dominant genes and how they are combined at the time of conception. If they are carriers of the same proteins, the percentage that the baby will develop a different set of antigens is less. If the genes are different, the possibility that the fetus will have a completely different set of agglutinogens increases. Thus, we can only predict what composition will be passed on to children.

Many fathers and mothers wonder whether the child’s blood type can be different from the blood type that the parents have? After consulting with a doctor or studying certain literature, they understand that this is a completely normal phenomenon.

How is the Rh factor inherited?

If each family member is Rh positive, but the child was born without a certain protein, with Rh-, then the question immediately arises: can the child’s blood type and Rh factor differ from his parents? Against this background, situations even arise when the potential father doubts his participation in the birth of the baby.

Genetics are involved in determining this indicator. The dominant gene is D (Rh+) and the recessive gene is d (Rh-). A person who has the Rh substance may be a carrier of the recessive gene (Dd). In a person with Rh negative there will be a set of only dd ( recessive genes).

Based on these data, we can predict whether this protein will appear in the baby. If both parents are Rh-, then the child will have the same genotype. After all, the parents are carriers of the recessive gene (dd), and there are no variants of the combination. If at least one of the partners has a dominant gene (D), then the child can be born with both positive and negative Rhesus.

There are cases when mother and fetus develop Rh conflict. In this case, the woman has (Rh-) and the child (Rh+). In this case, the mother’s body produces special antibodies that destroy the fetus’s red blood cells. This can be dangerous for the development of pregnancy. Although in some cases, the mother and doctors may not even know about this, since the pregnancy is proceeding normally, but they learn that the mother and child have a different Rh factor after birth.

This phenomenon can occur if the wife has (Rh-) and the husband (Rh+). Therefore, any pregnant woman should be under constant medical supervision. The consequence of Rh conflict between mother and fetus is hemolytic disease newborn, causing hypoxia, anemia, jaundice, dropsy of the brain.

If the first child in such a family was born with Rh positive factor, then in the future, during the pregnancy of the second and subsequent baby, the percentage of complications will increase.

But this is not a reason for concern and panic. Doctors are dealing with this issue. And if there is a threat of pregnancy, they will do everything possible to stabilize the woman’s condition so that she can carry and give birth to a child normally. To exclude complications, experts often recommend that couples take a blood test in advance, even before conception, in order to prepare for pregnancy.

A child’s blood type is not just an interesting statistical indicator, but also a factor that can have a significant impact on the condition of the newborn and the characteristics of its development. Parents should determine in advance the degree of probability of what blood type the baby may have and what the likelihood of developing an Rh conflict is. This will allow you to prepare for the possibility of activation of abnormal conditions that require immediate response and medical intervention.

Some experts even encourage future parents to carry out a similar calculation before deciding to start a family, in order to exclude the possibility of children being born with mutational or genetic diseases.

Factors that determine a child's blood type

All people are traditionally divided into four categories depending on their blood groups. To determine it, you just need to find out what the indicator of agglutinogens (A and B) and agglutinins is in human red blood cells and plasma:

• First (0) . There are no agglutinogens, only agglutinins are present.
• Second (A0). Agglutinogens A and agglutinins are present, with the former in the leading position.
• Third (B0). Agglutinogens B and agglutinins are present, the former again being in the leading position.
• Fourth (AB). A very rare combination in which agglutinogens A and B are present together.

The listed indicators in children directly depend on the data of the parents. Despite the fact that there is a detailed table that allows you to determine what kind of blood the baby will have, you can only find out exactly about all the probabilities of events by conducting thorough laboratory tests.

How is the Rh factor inherited?

The development of Rh conflict can pose a serious danger to the fetus, so at the moment experts pay attention immediately after establishing the fact of pregnancy. It develops in Rh-negative women and Rh-positive men, but not necessarily in 100% of cases. Modern medicine made it possible to develop a number of measures aimed at suppressing pathological condition, but this is a complex and lengthy process.

It happens that parents with Rh positive a negative child is born. The Rh factor can differ in physiological indicators, and there is nothing unusual in this. Everything is explained by the specific structure of blood cells, the peculiarities of the presence of protein on the surface of red blood cells and its activity. Rhesus inheritance is not always passed directly from parents to children, it all depends on which genes predominate in them, dominant or recessive.

We determine the child’s blood type according to the parents’ data

If you know what blood the mother has and what the father has, you can try to independently determine what indicator the baby will have. A child's blood type is inherited by passing on one gene from each parent:

• Parents with the first group can only have a similar baby.
• If one of the parents has the first group, and the other has the second, then the child will receive either first or second blood.
• If one of the parents has the first group, and someone has the third, inheritance occurs in exactly the same way. The result will be either first or third blood.
• When combining the indicators of the first and fourth groups, either the second or the third group can be obtained.
• The fourth group in combination with the second or third will give any result except the first group.
• Parents with the second and third blood groups can give birth to any babies, and it is impossible to know what kind of blood will be in which case. True, there are several tests that can predict the possible outcome as accurately as possible.

Advice: Don’t panic and immediately think that the child was replaced in the maternity hospital if your own calculation does not show desired result. It happens that antigens A and B are present in the human body in a passive form and do not manifest themselves in any way. True, this happens mainly in children from Asian countries.

This is only basic data, the final result may change under the influence of certain factors. It is impossible to influence these processes; you can only get as close to the result as accurately as possible using numerous tables and a calculator. IN isolated cases Even the established rules do not apply, so the baby’s blood parameters must be determined immediately after his birth, even if both parents have the first indicator.

Incompatibility of mother and child according to blood parameters

Finding out in advance what the mother’s blood data is and what the baby is expected to have is necessary for one more reason. Not many people understand that there is a risk of developing conflict not only in the Rhesus, but also in the group. When there are various antigens in the blood of the fetus and mother, a woman may begin to produce antibodies directed at the child.

Most often this happens in the following cases:

1. The first or third in the mother, the second in the fetus.
2. The first or second in the mother, the third in the fetus.
3. Any indicators in the mother, the fourth in the fetus.
4. Different blood counts in parents are also a mandatory indicator for establishing the presence of group antibodies in the pregnant woman and the fetus. The only exceptions are those cases when the father has the first blood group.

Despite the apparent complexity of the processes, all indicators can be established in just a few studies. At the same time, you should not rely only on your own knowledge; it is better to double-check everything by trusting professionals. If you know what blood type the child may have, it will be possible, if necessary, to make timely adjustments to the coordination of the pregnancy, think through a plan for the birth and further management of the baby. We must not forget about the risks of bleeding during childbirth; doctors must be prepared for anything in order to reduce the possibility of a negative outcome of a natural and so important process.

It is a known fact that the number of people with blood groups I and II (about 40% each) exceeds those with III and IV. What determines blood type in general, and how does a child inherit it from his parents?

Blood group is a kind of personal identifier. It is considered unchanged throughout a person's life, like fingerprints, and is passed on from parents to children. More than a hundred are now open various groups blood, but the main value is still in the AB0 system (read - a, b, zero).

There may be antigens A and B on the membrane of human red blood cells. The presence of antigens of the AB0 system is determined in the laboratory by reaction with control blood sera that contain antibodies to antigens A and B. Antibodies to antigen A are designated as α (alpha), to B - β (beta). Other names for these antibodies are anti-A and anti-B (that is, against antigens A and B). When antigens and antibodies of the AB0 system interact, erythrocytes stick together (scientifically called agglutination), therefore antigens A and B are also called agglutinogens, and antibodies α and β are called agglutinins. During agglutination, conglomerates (clusters) of red blood cells are formed, which cannot pass through small vessels and capillaries and clog them.

Antigens, like all proteins in the body, are inherited, namely the proteins, and not the blood groups themselves, therefore the combination of these proteins in children may differ from the combination in the parents, and a different blood group is obtained.

I (0) – blood group is characterized by the absence of antigens A and B; the plasma contains agglutinins α and β.

II (A) – established in the presence of antigen A, agglutinin β is present in the plasma.

III (B) – B antigens, in plasma – agglutinin α.

IV (AB) – antigens A and B, there are no agglutinins in the plasma.

Parents with blood type I will give birth to children who lack type A and B antigens.

Spouses with blood groups I and II have children of the corresponding groups. The same situation applies to children whose parents are from groups I and III.

People with blood group IV can have children with any group, with the exception of I, regardless of what type of antigens are present in their partner.

The most unpredictable inheritance of a child is the union of owners with groups II and III. Their children are equally likely to have any of the four blood types.

The Rh factor, or Rh, Rh is one of the 30 blood group systems currently recognized by the International Society of Blood Transfusion. The Rh factor is an antigen (protein) found in red blood cells. It was discovered in 1940 by Karl Landsteiner and A. Weiner. Their discovery helped determine that about 85% of people have this same Rh factor and, accordingly, are Rh positive (Rh+). The remaining 15% who do not have it are Rh negative. Inheritance: R – Rh factor gene, r – absence of Rh factor.

Inheritance of blood type and Rh factor occur independently of each other. If both parents are Rh positive (RR, Rr), the child can be either Rh positive (RR, Rr) or Rh negative (rr). If one parent is Rh positive (RR, Rr), the other is Rh negative (rr), the child may be Rh positive (Rr) or Rh negative (rr). If the parents are Rh negative, the child can only be Rh negative.

Since ancient times, blood has been considered a special, almost magical liquid. It was with her that they connected family connection children and adults. That’s what they said – “blood relationship”, emphasizing the special strength of this connection. Today, people are trying to explain character traits or eating habits through blood group. It is therefore not surprising that parents are interested in what kind of blood their child may have.

And it is equally important for doctors to know what blood type the parents of the unborn baby have. And this question is by no means an idle one. The course of pregnancy and the health of mother and child depend on how they are combined in the parents and the unborn child, the likelihood possible complications. Some of these relationships have already become a medical axiom, while others are only talked about by practicing doctors.

Let's try to figure out how the blood groups of children and parents are related: the inheritance table will help us with this.

Although this scarlet liquid was always treated as something special and its connection with human life and health was understood, the real properties were not known for a long time. Only in 1900, the Austrian doctor and scientist Karl Landsteiner, who studied blood serum, made a discovery that later brought him Nobel Prize, and allowed humanity to use the transfusion of this life-giving liquid in treatment as a completely ordinary and familiar procedure.

The scientist took blood from himself and five of his employees, separated the red blood cells from the serum and mixed their samples with the serum different people. Karl Landsteiner discovered that red blood cells behave differently in different combinations. In some cases, the red blood cells "stick together" to form clots, but in others they do not.

Decoding the results allowed him to initially identify three blood groups depending on the presence or absence of special particles, which he designated as A and B, and the absence as 0. Later, his successors identified another group, which contained both AB markers at once. Then they began to be designated by Roman numerals. Today, the generally accepted classification of blood groups looks like this.

This made it possible to determine blood compatibility and predict its behavior when transfused from one donor to another.

Rh factor

Further research into the properties of blood revealed another factor that affects its compatibility. In 85% of people, a special lipoprotein was found located on the membranes of red blood cells, called the Rh factor. Those who have it are Rh positive (Rh+), those who do not have it are Rh negative (Rh-).

The presence or absence of this antigen does not affect human health in any way, but acquires great importance For expectant mother. Since the child forming and growing in it has its own blood group with the Rh factor, this can lead to a conflict with the mother’s immune systems oh, especially with a second pregnancy.

That is why parents of the unborn child are asked to undergo tests to determine the blood type and Rh factor. If the Rh factor of the father and mother is the same (both positive or both negative), then there is no reason to worry. But if the rhesus levels of the expectant parents are different, then the onset and course of pregnancy requires closer attention from doctors.

The option is especially difficult when the mother is Rh negative and the father is positive, since most often the baby inherits Rh positive. This leads to the occurrence of Rh conflict between the mother’s body and the fetus, especially with repeated pregnancies.

Why the blood types of the child and parents do not match

How to recognize a group in children

To find out the possible blood type and Rh in children, you need to know exactly the characteristics of this vital moisture of the father and mother. The inheritance of these parameters is determined by the same laws of genetics as.

Table 1. Inheritance of a child’s blood type depending on the blood groups of the father and mother

Table 2. Inheritance of the blood type of the Rh system, possible in a child, depending on the blood types of his parents

As we know, a baby can only get what his parents have. But sometimes parents may hide hidden recessive genes behind a dominant trait, and then two brunettes suddenly give birth to a blond child. But two blondes cannot give birth to a brunette. So it is with the Rh factor.

A positive Rh factor is a dominant trait, so it is most often inherited. If both parents have negative Rh, then their children will have a similar Rh- without variants. But in mixed couples, or even if both parents are Rh positive, but there are hidden Rh- genes, in this case there is a possibility of having a baby with Rh-.

Pattern of inheritance

As already noted, the blood type is determined by the presence or absence of agglutinogens A and B in its composition. The type of blood a baby will have is influenced by the groups of parents. The easiest way is if both parents have the first group. This means that there is neither A nor B in the blood, therefore their children can only have the same group. In all other cases possible in children various options. It will be possible to know exactly about the baby’s blood type only after the analysis has been performed.

Human blood groups. Tips for parents

Thanks to modern science Today it is possible to predict the character, state of the nervous and immune systems of the unborn child only by the blood type of the parents. The blood type, calculated by comparing the Rhesus and blood groups of the parents, tells about many characteristics of the unborn child - about the color of his eyes, hair, predisposition to certain diseases, even about gender.

The Austrian geneticist Karl Landsteiner divided human blood into 4 groups based on the structure of red blood cells, finding out that special substances in it - antigens A and B, are found in various combinations. Based on this information, Landsteiner compiled the definitions of blood group:

I(0) blood group - without antigens A and B;
II(A) - antigen A;
III(AB) - antigen B;
IV(AB) - antigens A and B.

What blood type a child will have is shown by Mendel’s pattern, a scientist who proved inheritance by all kinds of blood parameters, primarily by group.

The blood type never changes - having received one antigen from mom and dad at conception, respectively, the child begins to develop in the womb according to genetics. Thanks to this science, people began to prevent many problems with the fetus, in particular, to predict defects and complications.

Gene relationships

Even at conception, genes are transmitted to the child from the parents, containing information about the presence of antigens and the pole of the Rh factor.

For example, blood group without antigens - the first - is inherited from parents who both have the 1st group.

The second group is compatible with the first; the child will have either the first or 2nd blood group (AA or A0).

The third group is obtained in a similar way - BB or B0.

The fourth is the rarest; either antigen A or B is transmitted to the child.

All these facts are confirmed, but still a theory, so exact results for the group can only be determined using laboratory tests. Today, with a high percentage of probability of coincidence, inquisitive parents or doubtful obstetricians managing the pregnancy, the group of the unborn child is calculated according to approximately the same scheme as given in the following table.

Table of inheritance of a child's blood type depending on the blood groups of the father and mother

Parents / Child's blood type B percentage
0+0 / 0 (100%)
0+A / 0 (50%) A (50%)
0+V / 0 (50%) V (50%)
0+AB / A (50%) B (50%)
A+A / 0 (25%) A (75%)
A+B / 0 (25%) A (25%) B (25%) AB (25%)
A+AB / A (50%) B (25%) AB (25%)
B+B / 0 (25%) B (75%)
B+AB / A (25%) B (50%) AB (25%)
AB+AB / A (25%) B (25%) AB (50%)

Rh factor

The Rh factor, which determines blood types, was discovered in 1940 by Karl Landsteiner and Alexander Wiener. This was 40 years after the discovery of 4 groups - the AB0 system. Over the past half century, geneticists have learned much more about the processes responsible for the type of Rh factor. Rh blood factor may be the most genetically complex of all blood type systems, as it includes 45 different antigens on the surface of red cells that are controlled by two closely linked genes on the chromosome.

The definition of Rh+ or Rh- is a simplification. There are many variations of the Rh blood type depending on which 45 Rh antigens are present. The most important of these antigens for mother and fetus is the Rh conflict. When a person is identified as Rh+ or Rh-, it is usually in reference to the D antigen. In other words, an individual is Rh + or RhD-.

Child inheritance table of Rh factor

Protein as a substance predominates in the red blood cells of most people (85%), which are capable of inducing intense antigenic reactions. A person who has a protein substance in the blood is with a positive Rh factor. A person who does not have the protein substance is Rh negative. Under ordinary circumstances, the presence or absence of the Rh factor has no bearing on life or health, except when positive and negative forms are mixed. The Rh factor was first identified in the blood of macaques in 1940.

The Rh factor is a protein inherited from parents on the surfaces of blood cells. Rh positive is the most common blood type. Having an Rh negative blood type is not a disease and does not usually affect your health. However, it may affect pregnancy. Pregnancy requires special care if the mother is Rh negative and the baby's father is Rh positive.

Rhesus blood conflict between mother and child

The Rh factor of blood, a dominant trait, is also related to genetics, because the mismatch of its poles leads to a conflict that is detrimental to the baby and the expectant mother.

If the mother has Rh-, and the child, which unfortunately happens, has the opposite Rh - Rh+, there is Great chance miscarriage. Usually manifests itself as an inheritance from one of the parents.

Rh conflict occurs only when the fathers are positive and the child and mother are Rh negative. So, the Rh+ father can have either the DD or Dd genotype, there are 2 possible combinations with different risks. Regardless of the genotype of the father, if he is Rh+ and the mother is Rh-, doctors assume in advance that there will be an incompatibility problem and begin to act accordingly.

This means that only Rh+ children (DD) are likely to be born with medical complications. When both the mother and her fetus are Rh (DD), the birth should be normal.

If a woman becomes pregnant for the first time and is Rh-, then there is no problem of incompatibility for her Rh-positive fetus. However, second and subsequent births can have life-threatening consequences for Rh+ children. The risk increases with each pregnancy. In order to understand why firstborns, as a rule, have the most safe birth and why later babies are at risk, you need to know some of the functions of the placenta.

Placenta and blood circulation

This is the organ that attaches the fetus to the wall of the uterus using the umbilical cord. Nutrients and the mother's antibodies are regularly transferred across the placental borders to the fetus, but her red blood cells are not. Antigens do not appear in the mother's blood during the first pregnancy if she has not previously been in contact with Rh + blood.

Thus, her antibodies do not “stick together” with the red blood cells of her Rh+ fetus. Placental ruptures occur at birth, so that fetal blood enters the mother's circulatory system, stimulating intensive production of antibodies to antigen Rh-positive blood. Just one drop of the fruit actively stimulates the production of large quantities of antibodies.

Whenever next pregnancy, transfer of antibodies from circulatory system mother again occurs through the placental boundaries of the fetus. Antigens, antibodies, which she now produces in reaction with the blood of the fetus - with a positive Rh factor, as a result of which many of its red cells burst or stick together.

A newborn may have life-threatening anemia due to lack of oxygen in the blood. The child also usually suffers from jaundice, fever, and has an enlarged liver and spleen. This condition is called erythroblastosis fetalis.

Standard treatment in such severe cases- mass transfusions of Rh negative blood for children with simultaneous drainage of the existing circulatory system to eliminate the flow positive antibodies from mother. This is usually done for newborn babies, but can be done before birth.

Serums for transfusion

Blood groups and their compatibility were originally used in research to invent a serum to introduce a blood antibody sample. If the serum agglutinates red cells, then Rh is positive; if this is not the case, it is negative. Despite the actual genetic complexities, inheritance of this trait can generally be predicted using a simple conceptual model in which there are two alleles, D and d. Individuals who are homozygous for dominant DD or heterozygous for Dd are Rh positive. Those who are homozygous recessive DD are Rh negative (meaning they lack key antigens).

Clinically, the Rh factor pole, like ABO factors, can lead to serious medical complications. The biggest problem with group and rhesus is not so much the incompatibility for transfusion (although that can happen), but the risk to the mother and her developing baby in the womb. Rh incompatibility occurs when a mother is negative and her child is positive.

Maternal antibodies can cross the placenta and destroy fetal blood cells. The risk increases with each pregnancy. For Europeans, this problem accounts for 13% of their newborns being potentially at risk. With preventative treatment, this number can be reduced to less than 1% of patients receiving bad news. Nevertheless, Rh incompatibility remains the leading cause of problems with risks for the development of the fetus and newborn, and the continuation of pregnancy.

Interpretation of transfusion

Because the baby's own Rh+ red blood cells will be replaced with negative ones, the mother's antigens and antibodies do not require additional red blood cells. Later, Rh- blood will be replaced naturally, as the child’s body gradually produces its own Rh+ red blood cells.

Erythroblastosis can be prevented in women with high risk(i.e. women with negative group with a positive spouse or a spouse whose blood is compatible) by administering serum containing antibody antigens from maternal red blood cells at 28 weeks of pregnancy, and within 72 hours after confirmation positive group blood of a child.

This should be done for the first and all subsequent pregnancies. The injected antibodies quickly “glue together” any baby's red blood cells as soon as they enter the mother's body, thus preventing her from forming her own antibodies.

Serums provide only a passive form of immunization and quickly leave the mother's blood. Thus, it does not produce any permanent antibodies. This treatment can be 99% effective in preventing erythroblastosis, and also for women after miscarriage, rehabilitation after ectopic pregnancy or induced abortion.

Without the use of serums, a woman with a negative Rh factor is likely to get a large number of positive antibodies every time she becomes pregnant if she comes into contact with an Rh-positive factor. Thus, the risk of life-threatening erythroblastosis increases with each subsequent pregnancy.

Signs of conflict with AB0

Anti-Rh+ antibodies may be obtained from an individual with Rh- blood as a result of a transfusion mismatch. When this happens, the likelihood of producing antibodies throughout life increases. Serums can prevent this.

Mother-fetal incompatibility can lead to a match with the ABO blood group system. However, symptoms are usually not that severe. This occurs when the mother and her baby are B or AB. Symptoms in newborn infants include jaundice, mild anemia, and elevated levels bilirubin. These problems in the newborn can usually be successfully treated without blood transfusion.