One of the first and most important tests that pregnant women should have is blood. This basic analysis determines what type of blood you have and what your Rh factor is. And is that Rh factor will play an important role in the baby's health.
The Rh factor is a protein present in the cells and, according to their blood type, each person has specific proteins of that type of blood on the surface of the red blood cells. There are four blood groups: A, B, AB and O.
In turn, each of the four blood groups is classified according to the presence or not on the surface of the red blood cells of another protein that determines the Rh factor. If the person is a carrier of this protein, it is Rh positive; If it is not a carrier, it is Rh negative.
The majority of the population, 85%, has that certain amino acid sequence that is commonly called Rh + in common language. There are many possible combinations depending on the Rhs of the parents, but Rh sensitization or Rh incompatibility can only occur when the mother is Rh negative and the father Rh positive.
In Babies and more, what blood group and Rh factor will my baby inherit?Rh negative mother and Rh positive father
Among all possible combinations, the risk exists when the blood group of the Rh- woman and that of the Rh + man are combined, although there would be no risk if the baby inherits the mother's Rh-.
But when an Rh negative woman and an Rh positive man conceive a child, there is a possibility that the baby has health problems. It is possible that the baby that is forming inside the mother that is Rh negative has Rh positive blood that she inherited from the father.
Approximately half of the children with an Rh negative mother and an Rh positive father are Rh positive.
It should be noted that possible adverse effects would not normally occur in the first pregnancy, but in the following.There is no risk of Rh incompatibility in the first pregnancy
The mother is usually not sensitized in the first pregnancy, but in the second or subsequent ones; For these purposes, any previous pregnancy is considered first even if it has not come to term.
This means that, generally, Rh incompatibility is not a problem when it comes to a first pregnancy since, unless there is some kind of abnormality, the blood of the fetus does not enter the mother's circulatory system during pregnancy.
However, during delivery, the mother's and baby's blood may intermingle. If this happens, the mother's body recognizes Rh protein as a foreign substance and begins to produce antibodies (protein molecules in the immune system that recognize, and then destroy, foreign substances) to attack Rh proteins that enter her blood.
Pregnant Rh negative women can also come in contact with Rh protein (something that could produce antibodies) in Rh positive blood transfusions, spontaneous abortions and extrauterine pregnancies.
During the following pregnancies, the red blood cells of the fetus can pass into the mother's bloodstream as she feeds him through the placenta.
Rh antibodies are not harmless in the following pregnancies, since if the mother conceives an Rh + baby, the woman's organism will now recognize Rh proteins as foreign bodies. Then your antibodies will pass into the baby's bloodstream to attack those cells.
What is the Coombs Test?
That is why it is so important to detect from the beginning of pregnancy if the mother has begun to generate antibodies. For this, a test called indirect Coombs Test, also known as indirect antiglobulin test, is performed.
It is a non-invasive test that is performed through a blood sample from the mother in the first trimester, in the 8th or 9th week, and is repeated in the second trimester, in the 26th week of pregnancy.
In Babies and more Rh incompatibility: preventionConsequences of Rh incompatibility for the fetus
If the mother's organism begins this "attack" it can lead to the dilation and rupture of the baby's red blood cells. When this condition occurs, it is known by the name of hemolytic disease or Rh disease of the newborn.
This disease, whose scientific name is "fetal erythroblastosis," is a blood disorder whereby, given different blood types, a mother produces antibodies during pregnancy that attack the red blood cells of her own fetus.
The name erythroblastosis is due to the appearance in the circulating blood of a high amount of erythroblasts, which are precursors of the red blood cells, which have been released into the circulation.
The severity of this condition can vary widely. In some cases, the baby has no symptoms of the disease; in other cases it can lead to the death of the baby before or shortly after birth. This disorder can be treated in the uterus (before the baby is born) through an intrauterine transfusion.
When the baby is born, the signs that may occur as signs of Rh incompatibility are: enlarged liver or spleen, generalized swelling, jaundice and anemia. After birth, depending on the severity of the condition, a blood transfusion is usually necessary.
Which is the treatment?
In the past it was much more complex, but at present the treatment is very simple. To prevent the sensitivity produced by Rh incompatibility are used special immunoglobulins called RhoGAM.
Whether the test results are positive or negative, if the father has a positive Rh factor and the mother negative, the pregnant woman receives an injection of anti-D gammaglobulin around week 28 to prevent the manufacture of antibodies during childbirth, when the The mother's blood can be mixed with that of the baby, and another injection within 72 hours after delivery to prevent the mother from generating antibodies.
If the woman has already developed the antibodies, the pregnancy should be followed closely to check that Rh levels are not very high. Only in exceptional cases if the incompatibility is very serious and can put the baby at risk are blood transfusions called blood exchange transfusions during pregnancy and after delivery.
The exchange transfusions replace the baby's blood with red blood cells with Rh negative factor to minimize the damage that the circulation of Rh antibodies already present in your blood flow can cause.
Photos | iStockphoto and Arek Socha on Pixabay
