A serological conflict may arise when the mother has Rh- and the father Rh +. Then the body of the future mother perceives her own child as something foreign and attacks them with antibodies. Fortunately, medicine can deal with serological conflict. What is D antigen and when is anti-D immunoglobulin administered? What are the causes of a serological conflict and how to prevent it?

Serological conflictcomes from the fact that human blood is not the same in everyone - there is a certain factor in the blood of some people, the so-calledantigen D , but not in others. It may happen that the unborn child has it (inherits from the father), and the mother does not.

Serological conflict - what are the causes?

When the mother's body "realizes" that there is a new, unknown particle in the blood of the fetus, it treats it as an intruder, something foreign, and in a protective reflex it produces antibodies to destroy the "foreign". Mom's body "finds out" about it only when her blood comes into contact with the fetal blood, and this usually only happens during childbirth or miscarriage.

Therefore, in the case of the first pregnancy, there is almost no risk to the baby, because the mother's body has no time to attack the baby. And even if it does produce antibodies, they are very weak at first and cannot overcome the placental barrier. It is not until 1.5 to 6 months later that stronger antibodies are produced that can cross the placenta.

They stay in the mother's body and if they cross the placenta and enter the fetal bloodstream during the next pregnancy, they will attack the fetus's red blood cells. This is the phenomenonserological conflict .

Serological conflict - table

Each of us has a specific blood type (A, B, AB or 0), but there is something else that makes our blood different. Most people have so-called D antigen, while others do not.

Originally, the D antigen was found in Rhesus monkeys, so it was named the Rh factor.

The blood of people who have Rh factor is called RH +, while others have blood of RH-. The former are definitely more, as much as 85 percent, while people with Rh blood - they constitute 15 percent. human population.

So, most mothers-to-be are Rh + (to check it out, the doctor already during the first onethe visit is ordered by a blood test). If you also have RH + blood,serological conflictyou will not be in danger, because the problem does not concern you.

And when you belong to this 15% minority with RH- blood, then it is important what Rh factor the father of the child has. If it is also negative, it means that your child will also have RH- (the factor is inherited from one of the parents) and it will be safe, because the Rh of the mother and child will be the same.

A serological conflict can only arise if the child's mother has RH- and the father has RH +. And of course, when the fetus inherits the RH factor from the father (60% of the time).

Important

The blood from the fetus entering the mother's bloodstream is favored by:

  • miscarriage
  • bearing detachment
  • ectopic pregnancy
  • hemorrhages
  • intrauterine procedures
  • prenatal testing
  • cesarean section
  • surgical delivery, e.g. with forceps

At least 0.2 ml of fetal blood must enter the mother's body for antibodies to form.

Every expectant mother up to the 12th week of pregnancy should have the blood type, Rh factor, and (if she has Rh-) marked for the level of antibodies attacking the fetal red blood cells.

Serological conflict - effects

In the past, a serological conflict could cause a very serious anemia, jaundice, and even death to the fetus.

Currently, medicine, even in the event of a conflict, can save a child, but most of all it tries not to let them go, preventing the formation of antibodies.

Serological conflict - how to prevent. Vaccine

As already mentioned, the main effort in medicine is to avoid conflict. To this end, all pregnant women with Rh-blood are given an injection of anti-D immunoglobulin (also known as anti-RhD or Rhogam).

It is a natural blood product that prevents the formation of harmful antibodies in the mother's body - in such a way that it immediately destroys all the fetal blood cells that could have entered the mother's bloodstream. Because when there is no sensitizing factor (D antigen), no antibodies can be made against it.

Some doctors recommend two doses of anti-D immunoglobulin - one in the 28th week of pregnancy and the other shortly after birth.

The effectiveness of such prophylaxis is 99 percent. In Poland, immunoglobulin is usually administered only once - after delivery (up to 72 hours after the birth of a child). Such prophylaxis is effective in 96-98 percent. Women with the factor should also receive immunoglobulinRh-, in which:

  • ectopic pregnancy removed
  • miscarriage found
  • there was a severe haemorrhage in the second or third trimester of pregnancy
  • have undergone invasive prenatal tests (amniocentesis, chorionic villus sampling)
  • have had an abortion.

Either of these situations increases the risk of blood entering the mother's bloodstream. In exceptional cases (when immunoglobulin was not administered or the blood of the mother and child was mixed before it was administered), the mother's body produces antibodies that can destroy the fetal red blood cells with a positive Rh factor (this applies to about 1.5% of women whose fetus has Rh + ). Then what?

Serological conflict - how to treat?

When special blood tests (the so-called Coombs test) show that the mother's blood has anti-D antibodies, she should be under special medical care. The level of antibodies in her body must be kept under constant control.

For this purpose, additional tests are performed at 28, 32 and 36 weeks of pregnancy. You should also have an ultrasound every 2-3 weeks to check how the serological conflict affects the baby.

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During this examination, the doctor assesses the size of the placenta and the fetus, swelling and exudation into the cavities of the fetus, and its viability.

When the level of antibodies is low - the risk is low and medical intervention may be required. On the other hand, when there are so many antibodies that they threaten the baby's safety, doctors may decide to terminate the pregnancy earlier and give the baby a blood transfusion.

It is very rare that a blood transfusion is needed before delivery, but it is also possible.

Cross-placement of anti-D antibodies increases after 16-18. weeks of pregnancy, and the greatest is in the third trimester, therefore a conflict pregnancy should end in the 37th or 38th week of its duration.

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