Why do parents and children have different Rh factors: what if the father and mother are positive, and the offspring are negative? Rh - negative pregnancy - what is the conflict? Two negative Rh factors in parents

Based on the level of antibodies in the blood of a pregnant woman, the doctor can draw conclusions about the expected Rh factor in the child and determine the onset of the Rh conflict.

Prevention of Rhesus conflict

If there is a risk of Rh conflict, a woman is tested repeatedly during pregnancy for the presence of Rh antibodies. If they are not there, it means that the woman is not sensitized and there will be no Rh conflict during this pregnancy. Immediately after birth, the baby's Rh factor is determined. If Rh is positive, then no later than 72 hours after birth the mother is given anti-Rh immunoglobulin, which will prevent the development of Rh conflict in a subsequent pregnancy.

Anti-Rhesus immunoglobulin breaks the immunological chain and prevents the production of anti-Rhesus antibodies. This drug also binds aggressive antibodies formed in the mother’s blood and removes them from the body. Timely administration of anti-Rh globulin with a high degree of probability prevents the development of Rh conflict during subsequent pregnancy.

You will do the right thing if you find out in advance at the maternity hospital where you plan to give birth whether they have anti-D immunoglobulin (of course, if you have a negative Rh factor); if they don’t, buy it in advance and take it with you!

IN lately the same vaccine is administered for prophylaxis during pregnancy (between the 28th and 32nd weeks) provided that the pregnancy is proceeding well and antibodies are in the blood expectant mother are not detected. After administration of the drug, the blood is no longer tested for antibodies.

Women with a negative Rh factor should carry out the same immunoglobulin prophylaxis within 72 hours after:

– ectopic pregnancy;
– abortion;
– placental abruption;
– amniocetosis (a test done by inserting a long, thin needle through the abdominal wall and into the uterus);
– spontaneous miscarriage;
- blood transfusions.

If a woman still has Rh antibodies and the fetus is Rh positive

If a woman has Rh antibodies in her blood and their titer increases, this indicates the presence of a Rh conflict.

The mother's antibodies cross the placenta and attack the baby's red blood cells. At the same time, it appears in his blood large number a substance called bilirubin. Bilirubin turns your baby's skin yellow (jaundice) and can damage his brain. As the fetus's red blood cells are continuously destroyed, its liver and spleen try to speed up the production of new red blood cells, thereby increasing in size. In the end, they also cannot cope with the replenishment of red blood cells. Severe oxygen starvation (anemia) occurs - the content of red blood cells and hemoglobin in the blood becomes alarmingly low, which can lead to a number of serious disorders in the fetus's body. This condition is called hemolytic disease.

In case of Rh conflict, treatment is necessary in a specialized perinatal center, where both the woman and the child will be under constant supervision.

If it is possible to bring the pregnancy to 38 weeks, a planned caesarean section is performed. If not, they resort to intrauterine blood transfusion: they penetrate the umbilical cord vein through the anterior abdominal wall of the mother and transfuse 20-50 ml of red blood cells into the fetus. The procedure is carried out under ultrasound control.

In emergency cases, within 36 hours after the baby is born, a replacement blood transfusion is performed, he is injected with Rh-negative blood of the same group as the mother, and resuscitation measures are carried out. The mother of such a child is not allowed to breastfeed him in the first days. This is explained by the fact that anti-Rh antibodies, which were formed during pregnancy, are passed to the newborn with mother's milk. And these antibodies seek to destroy the child’s red blood cells.

Let's sum it up

As soon as you decide to have a baby, take a blood test to determine the Rh factor. Moreover, not only you, but also your partner should do this. If the future father’s Rh factor is positive, and the mother’s is negative, then the probable Rh factor of the fetus is determined as 50% to 50%. In this case, a couple planning to become parents should consult a doctor: he will tell the expectant mother what preventive measures can prevent the development of Rh conflict. Do not neglect the advice of your gynecologist, listen to him and follow all the instructions he prescribes. If the doctor, looking at the test results, said: “Rh is negative,” do not be upset! If you are a vigilant and responsible mother, everything will be fine with your child.

Despite the prevailing stereotype that all people are initially equal, nature itself has endowed us all with distinctive individual traits. That’s why we differ from each other in color type, build, temperament... But if hair color and even figure can be changed at will, then there is a classification according to which you will under no circumstances be able to change your “environment” and move to another category. We are talking about four blood groups and only two variants of the Rh factor. These innate parameters cannot be changed during life at your own discretion and they are given once and for all. Moreover, throughout your life they have a direct impact not only on you, but also on your children and grandchildren. Therefore, they should be taken seriously. Especially the Rh factor, because its importance is practically equal to the importance of all other blood characteristics taken together. And they, in turn, are a direct reflection of the genetic code of each person, that is, in essence, his life, health, appearance, longevity, etc. Thus, it becomes clear that the Rh factor strongly influences the offspring, as one of the most important stages and tasks of the body. But how exactly?

There are other systems for assessing and analyzing blood systems, and their number is regularly increasing. But they are of interest mainly to specialists (biochemical researchers, doctors, geneticists), and most people have never heard of them, and do not need this information. But everyone knows about the Rh factor, both men and women. The former can open their passport at any time and see a stamp indicating their blood type and Rh factor, made at the military registration and enlistment office at the beginning of conscription age. The latter will definitely encounter or have already encountered this concept as soon as they think about pregnancy and the birth of a child. The modern education system introduces schoolchildren to the concepts of blood group and Rh factor as early as basic course human anatomy. But, to be honest, school knowledge is often perceived by us as something imposed and is often perceived inattentively, forgotten soon after passing the test and receiving a grade on the relevant topic. And only with age and entry into adulthood, the value of this or that information is revealed to us in a new light. Fortunately, today there are no problems with access to any information, and as for such important knowledge about your own body as your blood type and its Rh factor, every doctor will be happy to tell you about them. We suggest refreshing your knowledge right now, without looking up from your computer screen.

What is the Rh factor? How to determine your Rh factor
The Rh factor (abbreviated simply Rh or Rh) is one of 29 blood group systems used worldwide today. For example, the ABO system (or the first, second, third and fourth blood groups) is the most common characteristic for assessing human blood, and the Rh factor is considered to be the second most clinically important system. Unlike blood groups, of which there are four, the Rh factor is characterized by only two options. It is either positive (Rh+) or negative (Rh-), which is determined, respectively, by the presence or absence of a special antigen protein (or, in scientific terms, lipoprotein) on the surface of red blood cells. In fact, there are more than 40 such antigens, and each of them is designated by its own code, consisting of numbers, letters and/or other symbols. But in determining the Rh factor, a key role is played by antigens of the so-called type D and, to a lesser extent, types C, E and E. Their presence or, conversely, absence determines the Rh status of a person. It is known that the vast majority of the population of our planet, more precisely 85% of Europeans and literally 99% of Asians, have a positive Rh factor, that is, there is a named protein on the surface of their red blood cells. And 15% of people, half of them, that is, as much as 7%, are natives of Africa, do not have Rh, that is, their Rh factor is negative. But even “Rh positive” people can have different Rh status.

The fact is that, as with the combination of chromosomes that influences the formation of the sex of the unborn child, we also get the Rh factor from our parents. And each of them, in turn, also has data received from his parents. Thus, if Rh was dominant in the blood of both parents, then the child will receive the Rh factor Rh+, that is, a positive Rh factor. The Rh factor Rr, that is, inherited from one parent with a dominant and from one with a recessive Rh factor, will also be dominant, but will behave differently when combined with other genomes in the future. And only if both parents have a negative Rh factor, then the child can also only be Rh negative: rr. Although the Rh factor of both grandparents will also definitely have an effect. Too difficult? Let's look at an example. Suppose that the father of the unborn child has positive Rh, and the mother has negative Rh. But there is also a grandmother with negative Rh. That is, we have the following initial data: father Rr and mother rr. In this case, the child can be born with both Rr and rr Rh factors with a 50/50 probability. If both parents have a positive Rh factor, but both grandfathers have a negative Rh status, then the children will receive the same number of dominant R and recessive r genes. And they can get the Rh factor of any of the options: RR (Rh+), Rr(Rh+), rr(Rh-). But note that the probability of a positive Rh factor will still be three times higher than the probability of a negative one: 75% versus 25% probability. In the office of a gynecologist-obstetrician, you can see a visual table where, at the intersection of different indicators of the parents’ Rh factors, the variants of the Rh factors of the unborn child are indicated. The same visual information can be easily found on the Internet in order to find out in an accessible form the chances of your heir to have positive or negative Rh status.

But at the same time, these tables, and even a blood test for the Rh factor, will make it possible to find out only one fact: whether the owner of the blood has a positive or negative Rh factor. More accurate data, that is, the presence of dominant and recessive traits in generations, can only be clarified as a result of more studies carried out exclusively in specialized clinics and/or genetics institutes. You can, of course, try to use reverse logic and calculate the type of Rh status based on children, but it is unlikely that anyone will do such painstaking calculations. It is enough to know that holders of negative Rh status under no circumstances can carry positive Rh in their genome and, accordingly, pass it on to their descendants. Rh positive always tends to dominate and as a result gives positive Rh status. And in general, genetics knows only three circumstances for inheriting Rh status:

1. Both parents with a negative Rh factor can only give birth to a child with the same negative Rh factor as theirs.
   
2. One parent with a positive and the other with a negative Rh factor has a chance of both Rh-positive and Rh-negative offspring, and a child with a positive Rh status will be born with a probability of six out of eight cases, while a child without Rh antigen - in only two out of eight cases.
   
3. Two Rh-positive parents with a probability of 9 out of 16 will give birth to Rh-positive children with completely dominant Rh children, and with a probability of 6 out of 16 - Rh-positive children with recessive and recessive inclinations. dominant traits and only in one case out of 16 will their child have negative Rh status.
   

In total, there are only 9 possible inheritance options for the Rh factor, and you and your children, as well as your parents, belong to one of them. You can find your option in the list right now:

1. 100% of children will have Rh-positive blood factor - Rh+(DD)
   

2. Mother is Rh negative - Rh-(dd)

   The father is Rh positive - Rh+(DD)

3. 50% of their children will have a Rh positive factor - Rh+(DD),

   50% of their children will have a Rh positive factor - Rh+(Dd).
   

4. The father is Rh positive - Rh+(Dd)

   25% of their children will be Rh positive - Rh+(DD),

   25% of their children will have a Rh-negative factor - Rh-(dd).
   

5. The father is Rh positive - Rh+(Dd)

6. The mother is Rh positive - Rh+(DD)

   100% of their children will have a Rh positive factor - Rh+(Dd).
   

7. The mother is Rh positive - Rh+(Dd)

   50% of their children will have a Rh positive factor - Rh+(Dd),

   50% of their children will be Rh-negative - Rh-(dd).
   

8. The mother is Rh-negative - Rh-(dd)

   The father is Rh-negative - Rh-(dd)

   100% of their children are Rh-negative (Rh-(dd).
   

Why go into all this complexity? Why even know and take into account the Rh factor, yours and your relatives? When and why might this information be useful? Firstly, the combination of dominant and recessive traits and the resulting heterozygosity of the organism is preserved in genes and can influence the formation of many subsequent generations. Secondly, genetic characteristics, including the Rh factor, do not exist on their own, but are inextricably linked with the physiological and anatomical characteristics of the fetus, child, and then an adult. Genetics have already learned to determine the color of the hair and eyes of the unborn baby, the shape of the teeth and the tendency to early baldness, the presence of musical abilities and the likelihood of ambidexterity long before the birth of the little man. But if these signs are more likely to be in the realm of parental curiosity, then the importance of early identification of genetic and/or inherited diseases and other abnormalities cannot be overestimated. Dominant and recessive traits, including the Rh factor, are determined during intrauterine development. And it is necessary to know the Rh status of a couple planning to become parents because of the existence of such a phenomenon as Rh conflict. Its probability is determined before the start of a planned pregnancy in order to avoid big problems during gestation.

What is Rh conflict? What to do in case of Rh conflict
Rh conflict is an incompatibility between the blood of the mother and child according to the Rh factor. You may ask, how is this possible, since a child is the fruit of the mother’s body and the result of crossing her genes with the father’s genes?! This is precisely why a discrepancy arises: when the positive Rh factor of the child, inherited from the father, “meets” the negative Rh factor of the mother. A situation arises that is paradoxical at first glance and completely logical when analyzed judiciously. Just remember, as stated at the beginning of the article, that a positive Rh factor is nothing more than the presence of a certain protein in the blood. The body of a pregnant woman with a negative Rh factor “does not know” about the existence of such a protein; it does not have it itself and has never encountered it. Therefore, when the Rh-positive blood of the fetus enters the mother’s body, the mother perceives this protein as something foreign and potentially dangerous to itself. And if so, it begins to produce antibodies against the fetal red blood cells, which carry the antigen protein responsible for the Rh factor. Of course, the blood of the mother and fetus do not mix directly. But their bodies inevitably exchange metabolic products, some cells and substances through the permeable walls of the placenta. In the same way, antibodies against a protein in the blood of a child with a positive Rh factor are sent to him from the mother. This protective mechanism, biologically verified and deeply “programmed” in a person, cannot be stopped, and the longer the conflict of Rh factors, that is, essentially, organisms, mother and fetus, lasts, the greater the number of antibodies hostile to the fetus. This poses a direct danger to the baby’s health, so doctors always find out in advance what Rh factor each of the future parents has.

The fetal red blood cells, attacked by the antibodies of the mother’s body, die and turn into decay products that are toxic and poison the blood, cells, organ systems, and most importantly, the embryo’s brain. One of the most concentrated substances, bilirubin, gives the baby’s skin a yellowish color. This is where the term neonatal jaundice comes from, which is actually a hemolytic disease (that is, a disease of destruction) of newborns. This must be understood in such a way that, of course, it is not the babies who are destroyed, but their blood cells. However, the harm from this is still considerable. In addition to the brain, the baby’s liver and spleen are affected, then other internal organs and their systems. Fortunately, modern medicine has reached a sufficient level of development to counter these dangers. At the first suspicion of the possibility of Rh conflict, a pregnant woman comes under the close supervision of specialists, and if Rh antibodies are detected, special measures are taken to smooth out the incompatibility of the blood of mother and fetus. Subject to timely diagnosis and disciplined implementation of the doctor’s instructions, a successful resolution of the Rh conflict is more than likely. To do this, in women with a negative Rh factor, the presence of antibodies in the blood is checked starting from the 8th week of pregnancy: it is at this time that the Rh factor appears in the fetus. If necessary, a drug containing anti-Rhesus immunoglobulin is injected into the body. In other words, although the Rh factor is inherited in a recessive-dominant manner and cannot be changed, with the right approach and sufficient awareness it does not threaten health at all - neither yours nor your loved ones. Therefore, know your body, love yourself and be healthy!

It is no secret that bearing a child is a difficult process and is fraught with many dangers and nuances, for example, a negative Rh factor in a woman during pregnancy. If you believe the statistics, many lives have been claimed by the lack of knowledge of what blood type and Rh factor a person has. This is one of the most common factors in miscarriages. Every expectant mother should have an idea about the Rh factor, Rh conflict, as well as other nuances of this pathological process.

The concept of the Rh factor and Rh conflict

Blood is one of those human systems that is constantly under the radar of scientists. From time to time new systems are found in it. The most important and widespread blood system is the ABO system. In it, experts identified a specific antigen D, which is responsible for the Rh factor.

Based on the localization of antigen D, one can safely determine the Rh factor of the circulatory system. If D is found on the outside of red blood cells, then the Rh factor is positive. If a person does not have this antigen, then he is negative.

Thanks to the presence of this antigen, the subject's Rh is determined. With modern equipment, this diagnosis does not take much time and is not very expensive.

The chance that a child will have a positive Rh factor if the mother has a negative Rh factor and the father has a positive Rh factor is 65%.

It is the positive Rh in the fetus and the absence of it in the mother that can provoke an Rh conflict, since the body of the woman and the fetus constantly exchange various substances and substances through the blood system.

Everything happens as follows. Fetal blood enters the mother's body during blood exchange. The woman’s immune system detects antigen D in the incoming blood, identifies it as foreign and produces antibodies that harm the child by destroying his circulatory system.

It is important for every person, especially women, to know their Rh factor and blood type. This data is most often required during emergencies and can save a person's life.

The effect of negative Rh on pregnancy

But Rh conflict occurs not only with an Rh-positive father.

• the fact of a second conception with the presence of such a reason, a negative factor in a pregnant woman;
• penetration of the baby’s blood into the woman’s body during the first pregnancy;
• blood transfusion into the mother's circulatory system before pregnancy, if the Rh factor was not taken into account;
• various pathological processes during the period of bearing a child: exfoliation of placental tissue, internal hemorrhages;
• the presence of diabetes of mellitus etiology in women with pregnancy.

Naturally, you should always know your Rh and be prepared for any force majeure, but nevertheless, the percentage of good births in Rh-negative women is very high, especially in the absence of the D antigen and in the father of the child.

During pregnancy in later stages, blood must be donated frequently in order to detect pathology in time and begin to eliminate it.

During the first pregnancy, the chance of pathology due to the Rh factor is extremely small, because the mother’s immune system has not yet formed a system of antibodies to the D antigen in the fetus and with minimal therapy the birth will go smoothly.

There may be a risk of blood deficiency in the child, but regular transfusion can solve this problem. In this case, the woman should be under the strict guidance of a gynecologist in order to avoid problems with the fetus.

At a certain point in pregnancy, there is a period characterized by a peak in the production of specific antibodies to the fetal antigen. At this point, you can give one injection, which is called immunoglobulin. It belongs to the gamma globulin fraction and its function is to prevent the development of maternal antibodies to the fetus in the future. This is very useful if parents are planning a second pregnancy.

If this drug is not administered to a woman, then with the advent of a second pregnancy, the likelihood of a Rh conflict increases significantly and carries with it consequences much worse than a mild form of anemia in a newborn. We are talking about a very terrible pathology - hemolytic disease. All red blood cells are destroyed, bilirubin levels rise and jaundice can be observed. The fetal brain is also susceptible to damage. The chance of giving birth to a healthy child, even with the necessary assistance, is very small.

It is worth appreciating the importance of a vaccine with immunoglobulin after the first pregnancy, because there are often cases of abortion by artificial means, because bearing a fetus in some cases is not humane to the parents or the baby. If an abortion was performed on a woman who has a negative Rh factor, then there should be no talk of a new pregnancy, because the consequences can be fatal.

Medicine does not stand still, and immunoglobulin very well solves the problem of antibodies developed by the mother to the fetus. Therefore, you need to make your plans about pregnancy in advance and in consultation with your doctor.

Features of management of pregnant women with negative Rhesus

Pregnant women who suspect an Rh conflict with the fetus need to go to the hospital as soon as possible in order to constantly be under the 24-hour supervision of doctors who, if something happens, will be able to provide the necessary emergency care.

But there is also a possibility that the pregnancy will be completely normal. The reason for this may be a reduced level of immunity in the mother, who will not be able to produce the required amount of antibodies in response to fetal antigens in a short period of time. But this has its drawbacks, because with a weak immune system there is a high risk of infectious and viral diseases, which can negatively affect pregnancy.

Antibodies need to be monitored at least once a week. This will help to diagnose Rh conflict in a timely manner and take urgent action to save the mother and baby.

It is worth noting that a negative Rh factor during pregnancy depends on your blood type. That is, it can be argued that blood type and pregnancy depend in direct proportion to each other. Negative blood type during pregnancy is the main cause of the problem. Thus, 1 negative blood group and 3 negative blood group cause Rh conflict more often than group 2. The third group, although it does not occur quite often, the chance of Rh conflict in its presence is very high. With blood group 4, Rh conflict does not arise, since there is no cause in the form of agglutinins. The fourth blood group of the mother is the most favorable and it is with the fourth group that you can not be afraid of getting pregnant.

Rh conflict has a negative impact on the fetus, the consequences of which can last a lifetime.

• diseases of the blood and cardiovascular system;
• diseases of the liver and gall bladder in the form of hepatitis and jaundice;
• diseases of the nervous system;
• increased risk of diseases that have a hereditary predisposition.

But don't despair. Modern medicine has found more than one method of dealing with Rh conflict; pregnancy with a negative Rh factor is possible and the consequences are not terrible if you follow some important rules.

Prevention and treatment of negative Rh factor

A few decades ago, women with a negative Rh factor were recommended to give birth to only one child, and doctors were categorically opposed to terminating the pregnancy with the first baby.

Today the situation is completely different, which is good news. With the help of preventive methods, if a woman has a negative blood group during pregnancy, she has the opportunity to freely make plans for the birth of her next children.

1. It is necessary to eliminate the production of specific antibodies by the woman’s body or reduce their number.
2. It is necessary to avoid certain procedures that increase the risk of fetal blood entering the mother's circulatory system.
3. Use immunoglobulin injections if necessary.

• prescribing a blood test for the presence of antibodies in the first trimester of pregnancy;
• if the titer is high, tests need to be repeated every week;
• constant monitoring of the fetus through tests and ultrasound examinations;
• if it is impossible to carry out a blood transfusion to the fetus, then it becomes necessary to induce labor, since any delays are dangerous for the baby’s life;
• A woman should be vaccinated only after cases such as abortion or conception outside the uterus.

It is important to remember that during the first birth the baby is most often not in danger if the woman has not received Rh-positive blood transfusions. The second birth is much more dangerous in terms of the occurrence of pathologies, but this can be avoided if immunoglobulins are administered to the woman in a timely manner.

There is no need to panic, because modern medicine has come a long way and the problem of negative Rh factor during pregnancy is easily solved. The main thing is that you need to spend more time under the supervision of doctors and monitor your health and the health of your baby.

Everyone knows that Rh conflict is bad, but few people know how it manifests itself and what it threatens. Unfortunately, ideas about this problem appear only when we are faced with its negative consequences, although they could have been avoided. That is why it is necessary to understand this issue.

The Rh factor is a system of human antigens that is located on the surface of the red blood cell. If the Rh factor is present in the blood, then “Rh positive” is determined, if it is not, then “Rh negative”.

Many women learn about their blood type and Rh factor already when they are pregnant, when registering at the antenatal clinic. Remember that your blood type and Rh factor do not change throughout your life, and you need to find them out as early as possible; to do this, donating blood from a vein once is enough.

What is Rh conflict?

If during pregnancy a woman’s body with Rh negative blood Rh-positive red blood cells of the fetus enter (we’ll talk about the reasons later), then her body begins to produce antibodies in response to the foreign antigen.

Repeated entry of Rh-positive erythrocytes causes massive formation of Rh antibodies, which easily overcome the barrier of the placenta and enter the fetal bloodstream, causing the development of the fetus and newborn. Antibodies are directed against the Rh factor on the surface of the red blood cell and lead to the destruction of fetal red blood cells.

Severe anemia develops in utero, which leads to tissue hypoxia, enlargement of the spleen and liver, and dysfunction of the internal organs of the fetus. When a red blood cell is destroyed, a large amount of bilirubin enters the blood, which, deposited in the brain, leads to encephalopathy and kernicterus. Untreated anemia and dysfunction internal organs progress steadily, the terminal stage develops hemolytic disease fetus - edematous, in which fluid accumulates in the chest and abdominal cavity. As a rule, at this stage the fetus dies in utero.

It is worth noting that Rh conflict is one of the reasons, but never affects conception and miscarriage in the early stages.

When should you be concerned?

Mom is Rh positive - dad is Rh negative: there is no reason to worry, this situation does not affect conception, pregnancy, or childbirth.

Mom is Rh negative - dad is Rh negative: There will be no problems either, the child will be born with Rh-negative blood.

Mom is Rh negative - dad is Rh positive: this situation requires special attention not only from doctors, but also from the woman herself, since your health is in your hands, and all subsequent information is extremely important to you.

Women with Rh-negative blood should approach the issue very responsibly. Remember that every unwanted pregnancy increases the risk of not having a baby in the future.

Situations leading to the development of Rh conflict

As mentioned above, the trigger point for the development of Rh conflict is the entry of Rh-positive red blood cells of the fetus into the bloodstream of the Rh-negative mother.

When possible:
artificial termination of pregnancy () at any time;
spontaneous miscarriage at any time;
;
after childbirth, including after;
nephropathy (preeclampsia);
bleeding during pregnancy;
invasive procedures during pregnancy: cordocentesis, chorionic villus biopsy;
abdominal injuries during pregnancy;
history of blood transfusion without taking into account the Rh factor (currently this is extremely rare).

All described situations require specific prophylaxis, the administration of anti-Rhesus gammaglobulin.

Prevention of Rhesus conflict

The only proven method of preventing Rh conflict at present is the administration of anti-Rh gammaglobulin - and patients should remember this first of all! All situations described above require the administration of anti-Rhesus gammaglobulin in the first 72 hours, but the sooner the better. For high effectiveness of the preventive action, it is necessary to strictly adhere to the timing of drug administration.

Pregnancy in a woman with Rh negative blood

After registering a patient with Rh-negative blood, it is recommended to determine the titer of anti-Rh antibodies in the blood monthly, starting from the early stages of pregnancy.

The first signs of possible hemolytic disease of the fetus are determined by the results of an ultrasound scan during pregnancy.

Home » Life " If the parents have a positive Rh factor. Negative Rh factor in a child - normal or pathological

My wife and I have positive Rh blood factors, and our son is negative. Could this really be possible? Nikolay N., Grodno region.

Viktor Andreev, professor of the Department of Medical Biology and General Genetics, GrSMU:

For a long time, people have noted that a child is not an exact copy of its parents. It happens that children have traits that are not characteristic of either the mother or the father.
Many hypotheses have been put forward to explain such observations. The most widely accepted concept is fused heredity. According to it, the totality of all the characteristics of each parent is transmitted as a whole to the descendant, in whom they are mixed and lose their individuality.

Proponents of this opinion consider the hereditary substance to be a fused and precisely divided material. Its symbol is blood. Echoes of such an idea are the expressions “purebred”, “half-breed” (in relation to animals), “consanguinity”, “blue blood” that have been preserved since the beginning of the 18th century. The difference between the offspring and the father and mother was explained by mixing, and between sisters and brothers - by the variability of the “blood strength” of the parents. The argument in favor of fused heredity is that some characteristics of the descendants are a cross between the characteristics of the parents. Such a speculative interpretation raises many questions for the spouses to each other.

The founder of the experimentally proven scientific theory of discrete (separate) heredity was Gregor Johann Mendel (1822–1884). The scientist discovered the fundamental laws of inheritance and showed that the descendant receives factors, which today are called genes, from each of the parents.
A gene determines the formation of one elementary trait, while the latter can have several specific manifestations (in genetics - phenes).

For example, the color of the iris is brown or blue; eyelashes - long, short or medium; lips - thin, full or medium full; hair is straight or curly. These varieties (versions, states) are called alleles. Of the alleles of a gene, only 2 can be in a person’s genotype - from the mother and from the father. Genes do not merge, but during the formation of germ cells they diverge independently of each other. One gamete (sperm or egg) gets one allele, and the other gets another.

Alleles can be dominant and recessive (from the Latin recessus - retreat); the latter are not phenotypically manifested in the presence of the dominant allele.
The dominant allele that determines the Rh-positive blood group is Rh; recessive, or hidden, - rh. Allelic pairs of genes are made up during fertilization - the egg will have one of the possible combinations: RhRh, Rhrh or rhrh.

If both parents have Rh-negative blood (their genotypes are rhrh and rhrh), then a child cannot be born who is Rh-positive.

In the case where the mother and father are Rh positive and their genotypes are homozygous for the dominant allele (RhRh and RhRh), all children will have Rh positive blood (RhRh genotype).

Since the author of the letter and his wife have a child with Rh-negative blood, then, according to the discrete theory of heredity, the parents are heterozygous by genotype, i.e., each genotype has both dominant and recessive alleles (the genotype of the father is Rhrh; the genotype of the mother is Rhrh; Rhrh). In such a family, a son or daughter can have both Rh-positive and Rh-negative blood.

Perhaps, while waiting for the birth of a baby, the question of how the Rh factor is inherited comes first only for women who fear Rh conflict. For other parents, the external characteristics and health of the unborn child are much more important. But it is worth noting that blood characteristics are no less important for a little person than hair color or eye shape, so it is worth familiarizing yourself with the concept of Rh (Rh) and the principles of its inheritance.

Rh positive and negative

In humans, there may be a group of lipoproteins on the surface of red blood cells; it occurs in approximately 85% of people, and in this case we are talking about a Rh-positive factor. But the absence of lipoproteins in 15% of children does not indicate illness or developmental anomalies, but only indicates negative Rh. The presence or absence of a lipoprotein group on an erythrocyte in most cases does not affect a person’s lifestyle in any way; only women with negative Rh during pregnancy have a risk of Rh conflict.

The lipoprotein formula has a rather complex composition; it includes various antigens, but the Latin D is used to designate the Rh factor:

• "+" is denoted by D;
• “-” is marked with the letter d;

In this case, D is a dominant gene, and d is a recessive gene.

It would seem that D + d will always give a “+”, but there are some nuances of inheritance of the Rh factor, in which both parents with a positive Rh factor give birth to Rh negative children.

A discrepancy between the Rh factor between parents and the child very often causes suspicions of infidelity and family quarrels, but in fact this is the norm and Rh-positive parents can give birth to Rh-negative children.

Why does this happen? To do this, you need to consider how parental genes are inherited and what a chromosome set is.

A little about genetics

Many people probably remember from school that all cells of the human body, except for the cells of the reproductive system, consist of two chromosomes carrying dominant and recessive genes.

The egg and sperm have the same chromosome set, and upon fertilization, a new cell is formed that has a unique combination of chromosomes, which is responsible for the external data and some characteristics of the fetus.

Rh, like other characteristics, is transmitted genetically, and when an egg is fertilized, the following combination can occur:

As you can see, in the second case, the combination Dd consists of a dominant and recessive trait, that is, children are born with Rh “+”, but also have the recessive gene Rh “-”. Of course, at the level of genetic research it is possible to determine which combination is present - DD or Dd, but this analysis is very complex and is not necessary.

To presumptively determine Rhesus, obstetricians use an inheritance table.

Having considered how Rh is formed, it can be noted that negative Rh is inherited in 100% of cases only from Rh-negative parents; in all other cases, the formation of both negative and positive Rh factors is possible. Moreover, how Rh is inherited is not affected by the gender of the parent; inheritance depends only on the dominant gene.

A little about Rhesus conflict

Many women with Rh “-” are afraid to give birth to a man with Rh “+”, fearing that they will not be able to carry and give birth to a healthy child. But this fear is not always justified.

• the maternal body, which does not have a lipoprotein component on the surface of red blood cells, perceives fetal lipoproteins as a foreign body;
• the pregnant woman’s immune system begins to actively produce antibodies that destroy the red blood cells of the embryo;
• During this process, a large number of red blood cells in the embryo die, which leads to miscarriage or loss of pregnancy (fetal death).

The blood type and Rh of the fetus are formed by the end of the 3rd month of development, and it is at this time that a pregnant woman can lose her child. But is there any hope for mixed rhesus couples to have healthy children?

In fact, everything is not so scary and methods have been developed that allow a woman to bear a full-fledged baby even with a negative factor.

1. A specific vaccination that suppresses the reaction of a woman’s immune system to foreign lipids. The vaccination can be done both before conception, when planning pregnancy, and immediately after determining an interesting position.
2. Regular monitoring by a doctor. Such women have to undergo tests and visit antenatal clinic more often than other groups of pregnant women in order to promptly identify the first deviations during pregnancy.

But only by the end of 3 months of gestation will it be possible to determine whether Rh “+” or Rh “-” is transmitted from the father. If a negative factor is detected in the fetus, then the pregnancy will proceed without the risk of embryo death due to the pregnant woman’s immune system.

Knowing about Rh inheritance helps to predict the Rh factor of the baby even before his birth. But in most cases, this information plays an important role only in preventing Rh conflict in pregnant women.

Many have heard of the term “Rh conflict”, but what does this term actually mean? The negative Rh factor itself is not nearly as scary as it might seem. It is not always the cause of Rh conflict, but it is advisable to take care of its prevention as early as possible - preferably even at the stage of pregnancy planning.

Only in this case will it be possible to reduce the likelihood of complications to a minimum. And is it really so terrible and inevitable if the expectant mother is Rh negative? We will examine these questions in the article.

What is Rh blood and what significance does it have when planning a child?

Rh factor is a protein found on the surface of red blood cells. There are about fifty types of these proteins. If at least one of them is present in the body of the expectant mother, it means that her Rh factor is positive, and if it is absent, then it is negative. In this case, only the D antigen influences the occurrence of Rh conflict.

The fact that protein is present or, conversely, absent in the human body does not mean that he has any disease or pathology. It's simply a genetic trait, just like eye color, hair color, or blood type.

According to honey statistics, Rh negative is not such a common occurrence, it occurs in only 15% of people in the world. And yet, if a woman is Rh-, you need to be especially careful when planning a pregnancy, since every unsuccessful attempt can lead to serious negative consequences for the possibility of becoming a mother.

How does it affect conception and fetus in the future?

The Rh factor itself does not affect the likelihood and ease of conceiving a child, but the different Rh factor of the spouses will have an impact on how the pregnancy will proceed later. Thus, the most favorable case is considered to be the case when the Rhesus of both potential parents is the same, but this is not always the case. Conception will not happen faster just because the couple’s Rhesus coincides, since this process is influenced by a lot of factors, but pregnancy will be easier when the future father and mother are both Rh-positive.

Rh negative in husband and wife also significantly reduces the risk of problems in the future. When a child inherits a positive Rh from the father with a negative blood type of the mother, the development of Rh-conflict disease is possible.

We invite you to watch a video about the influence of the Rh factor on pregnancy:

Does the absence of antigen D in a mother affect pregnancy?

Immunity protects a person from infectious diseases and this happens due to the fact that the body’s antibodies destroy foreign proteins and antigens that have entered it.

If the mother’s blood is Rh-negative, then, as her future baby is Rh-positive, the woman’s body perceives the fetus as something foreign and hostile, which is why it begins an immune attack against it. In this case, red blood cells in the blood of the unborn baby are especially at risk, as they are literally destroyed. This phenomenon is called Rhesus conflict and, if nothing is done, this phenomenon can lead to very unpleasant consequences.

It should be understood that negative Rh in the mother is not an indicator that Rh conflict is inevitable.

If the woman and the future baby are Rh negative, these problems simply will not arise. And even if the Rhesus of the mother and child do not match, it does not always occur.

Is it possible to get pregnant with different or the same values?

If positive in women and men

This combination is considered the most optimal. Most often, with it, pregnancy occurs quickly and there are no conflicts during conception.

If mom and dad are negative

As a rule, there are no problems with the possibility of conception in this case either. If infertility exists, it is not associated with negative Rh in both partners, but with some other reasons.

If the spouses are different

In this case, everything is not so clear. Most often, with different rhesus in partners, a woman manages to get pregnant, although she can carry it to term and give birth healthy child this does not always work out. In particular, the pregnancy of an Rh-negative mother with a Rh-positive child can lead to problems with pregnancy, but if the situation is the opposite, then no problems should arise. The body of a Rh-positive mother will not react negatively to a Rh-negative fetus..

What is Rh conflict in obstetrics, and why does it occur?

Rh conflict pregnancy - what is it?

In obstetrics, this concept is understood as any pregnancy accompanied by the production of antibodies directed against fetal cells. The Rh conflict itself develops in the same way as any other immunological reaction. It occurs due to the fact that a mother with a negative Rh factor and an unborn child who has a positive Rh factor exchange blood.

In this case, the mother’s immune system regards the presence of the fetus in her body as a foreign threat and begins to produce antibodies against it. For this to happen, it is enough that 35-50 ml of red blood cells from the blood of her future baby enter the woman’s body. However, even if there is incompatibility between the blood of the mother and child due to the Rh factor, the Rh conflict itself does not always arise.

For example, it happens that during such a pregnancy antibodies may not be produced at all, or there may be so few of them that they cannot cause serious harm to the health of the unborn baby.

There are a number of factors that increase the occurrence of Rh conflict during gestation. And not all of these reasons are associated with the blood of her unborn child entering a woman’s body.

The more “bloody” the obstetric intervention was, the greater the risk of immunization. The same thing happens if there was no bleeding, but the placental barrier was broken.

• At caesarean section this risk increases by 52.5%.
• With manual separation of the placenta - by 40.3%.
• Antepartum hemorrhage increases it by 30%.
• And with eclampsia, when the placental barrier is disrupted, the risk is 32.7%.

We invite you to watch a video about what Rh conflict is during pregnancy:

Probability when expecting your first baby

The first pregnancy is considered relatively safe in terms of Rh conflict. The fact is that usually the placenta reliably protects the fetus from the effects of antibodies, and they themselves either do not have time to be formed, or, if they are produced, then in very small quantities. To put it simply, the mother’s body does not seem to notice the developing fetus, and therefore the production of antibodies does not occur until the child’s blood begins to mix with the woman’s blood.

During the normal course of pregnancy, this usually happens during childbirth.

The likelihood of a baby coming into contact with antibodies produced by the body of his Rh-negative mother is extremely low, although possible. In general, the occurrence of Rh conflict during the first pregnancy is not frequent and is approximately 10%.

Probability when carrying a fetus for the second time

During the second and subsequent pregnancies, the likelihood of Rh conflict increases significantly. This is explained by the fact that an Rh-negative woman has already developed an immune memory, which leads to increased formation of antibodies to the D antigen contained in the blood of her Rh-positive baby.

The second and any subsequent pregnancies, regardless of how they proceeded and how they ended, become a catalyst that triggers the production of antibodies in the mother’s body.

However, this does not mean at all that a woman who has given birth to one child can no longer become pregnant, since this will certainly lead to an Rh conflict. A woman just needs to be more careful and responsible about controlling antibodies.

And the first thing that is required is not to refuse an injection of anti-Rhesus immunoglobulin when prescribed by the attending obstetrician-genecologist, if you plan to carry and give birth to your second baby healthy. This will allow the binding of foreign Rh-positive antigens and prevent the production of antibodies in the mother’s body, which significantly reduces the risk of complications during a subsequent pregnancy.

If antibodies were not produced during the first pregnancy, and immunoglobulin serum was administered on time, then when carrying a second baby, the probability of an Rh conflict will be equal to the same initial 10%.

What is the danger when a conflict develops?

Rh conflict can be very dangerous during pregnancy, since antibodies seriously attack the fetus’s body and destroy its red blood cells. In case of Rhesus conflict, massive destruction of red blood cells is observed, due to which a large amount of bilirubin, which has pronounced toxic properties, is released into the blood.

As a result, all organs and tissues of the fetus are damaged, but the baby’s nervous system suffers especially severely; for example, the tissues of his brain soften, which can lead to mental retardation. The spleen and liver, the main purpose of which is precisely to rid the body of bilirubin, do not cope with their function. And the massive death of red blood cells itself leads to the baby developing anemia and hypoxia.

All these three factors, launched together, lead to a serious complication - hemolytic disease of the fetus.

The consequences of complications - hemolytic disease of the fetus can be:

As for the Rh-negative mother, who has become the unwitting culprit of all these troubles, the Rh conflict itself will most likely not affect her health in any way, even if the developing fetus suffers from this. serious pathologies.

Sometimes, but not always, with a Rh conflict, the expectant mother may develop preeclampsia, which is a truly serious complication.

We invite you to watch a video about the dangers of Rhesus conflict:

Why can't abortions be done?

Why can’t a mother’s pregnancy be terminated if she has a negative Rh?

Doctors do not recommend women with negative Rhesus to have abortions, except perhaps medical indications, but even in this case, it is advised to think carefully before making such a decision. With each subsequent pregnancy, antibodies in a woman’s body are produced at an ever-increasing speed and in ever-larger quantities. And the possibility of a successful gestation of the fetus decreases significantly with each termination of pregnancy.

Parental blood group compatibility chart

What to do for prevention?

Even at the stage of pregnancy planning, a woman needs to have a blood test done in order to determine her group (if this has not been done before) and Rh status. If the potential mother is Rh negative, it will be necessary to find out the Rhesus affiliation of the future father. This should be done before pregnancy in order to keep the formation of antibodies under control from the very beginning.

It is advisable, even at the planning stage, to obtain specialist advice regarding the possible risks of Rh conflict occurring during gestation and its possible outcome.

In this situation, it is important to treat family planning methods with all possible responsibility.

That is, do not have abortions and try to preserve the first pregnancy as much as possible. And from the very beginning, from about 7-8 weeks, It is recommended to register and be observed by a doctor so that in case of complications associated with a negative Rh factor, the expectant mother was promptly provided with the necessary assistance.

Receive all necessary appointments from the supervising obstetrician-gynecologist, including mandatory vaccination with human anti-rhesus immunoglobulin rho(d).

To summarize, I would like to say that the negative Rh factor itself is not nearly as scary as it might seem. It is not always the cause of Rh conflict, but it is advisable to take care of its prevention as early as possible - preferably even at the stage of pregnancy planning. Only in this case will it be possible to reduce the likelihood of complications to a minimum.

Genetics is a stubborn thing and, at first glance, unpredictable.

Do you think that only in ancient times did poor mothers suffer from the evil gossip of their neighbors if suddenly a fair-haired baby was born to dark-haired parents?

In this article we will answer the following questions:

1. M Is it possible for the same parents to have children with different Rhesus factors?
2. M Can a child of Rh-negative parents be Rh positive?
3. E If mom and dad are Rh positive, can they have a Rh negative child?

And now a little genetics (simplified and visual).

How is the Rh factor inherited?

Each person has two genes responsible for the Rh factor. We take one gene from our father, another from our mother. Each of them can be:

R– Rh factor gene.

r– gene for the absence of the Rh factor.

Obviously, for humans there are only three pairs of Rh genes possible:

– RR (Rh positive person)

– Rr (a person with positive Rh who is a carrier of negative)

– rr (person with negative Rh)

R is a dominant gene, in combination with a minus it gives a plus :)

Therefore, Rh- positive people There are two types: RR and Rr. Unfortunately, if you have a positive Rh, no one will voluntarily tell you what type it is - RR or Rr.

A regular blood test for the Rh factor will only determine the fact itself - “you have a plus” (a more thorough study can be done for a fee at genetics institutes and large perinatal centers). But sometimes the type of positive Rh can be calculated from children :)

From personal experience:

Example No. 1. My mom has Rh +, my dad has Rh –, I have Rh -. This means that the mother is a carrier of the negative Rh gene, i.e. she has positive Rh type Rr (visually in diagram 2).

Example No. 2. I am Rh negative, my husband is Rh positive. The child was born with positive Rh. Because The baby inherits one gene from me, then he definitely has the Rr type (see diagram 2).

Rh-negative people (rr) cannot be carriers of positive rhesus (because it would then dominate and give a plus).

There can be only three situations of Rh factor inheritance in the world:

1. Both parents have a negative Rh factor.

On scheme 1 It is very clear that such parents can only give birth to Rh-negative children.

2. One parent is Rh-negative, the other is Rh-positive.

On scheme 2 it can be seen that in two cases out of eight they will have a child with negative Rh, and in six cases out of eight they will give birth to a Rh-positive child who is a carrier of the negative gene.

3. Both parents are Rh positive.

On scheme 3 it is clearly seen that in one case out of sixteen this couple may give birth to a Rh-negative child, in six cases Rh-positive children who are carriers of the negative Rh factor gene may be born, and in 9 cases out of 16 they will be Rh-positive (completely Rhesus factor dominant children.

If my explanations remain unclear to you, I will answer the questions:

1. Can the same parents have children with different Rhesus factors? They can.

2. Can a child of Rh-negative parents be Rh positive? No.

3. If mom and dad are Rh positive, can they have a Rh negative child? Yes.

From personal experience:

A friend of mine's husband thought he was Rh negative. And he assured everyone of this. My friend also had a negative Rhesus, so when a child was born with a positive Rhesus, the obstetrician said during childbirth: either from a neighbor, or your husband is lying.

Having survived the collapse on the maternity table, the angry woman finally obtained an official blood test from her husband, which confirmed that her husband was Rh positive!