For many “razorzusny” parents, the risk of Rh-conflict becomes a serious cause for concern. Others claim they already have Rh-positive children, and each of them was born healthy. So why does the Rh-conflict not arise in all cases? And how do you know for sure its risk?
What is Rh incompatibility
The Rh factor in blood is a special protein on the surface of red blood cells (erythrocytes).
When such a protein enters the Rh-negative (Rh-) organism, the immune forces of the latter develop protection – antibodies that attack the “enemy” when they meet him again.
In the case of pregnancy, we are talking about the mother’s antibodies “attacking” the fetal erythrocytes. As a result, pregnancy can end with hemolytic disease of the newborn (HDN), miscarriage or intrauterine death of the child.
Why does not everyone have a “conflict”
In order for the mother to have Rh antibodies, the fetal blood must enter her bloodstream in a sufficient volume.
This situation practically does not occur in healthy pregnancies, and according to statistics it is only about 10% of cases.
The threat of conflict increases significantly if pregnancy was preceded by abortions, miscarriages, threats of termination with placental abruption or complications in previous births.
In this case, class M antibodies first appear in the mother’s blood, which, due to their size, do not pose a danger to the fetus. IgM are simply not able to penetrate the placental barrier, which cannot be said about the class G antibodies that come to replace them.
IgGs are much smaller than their predecessors, easily penetrate the fetus and remain in the mother’s blood for many years.
Thus, a high risk of Rh-conflict already during the current pregnancy occurs only in women with a burdened obstetric and gynecological history. Whereas in other cases this risk is minimal.
How to check
All Rh-negative women, upon registration, are shown a blood test for the Rh factor and blood group.
The same analysis is recommended for the father of the child.
If the Rh factor of both parents is negative, there is simply nothing to worry about. But, if the dad turned out to be “positive”, the pregnant woman will have to donate blood for anti-rhesus antibodies every month until 28 weeks.
If antibodies still do not appear in the blood by the specified time, the woman will be sent for the prophylactic administration of anti-rhesus immunoglobulin, and the search for antibodies will stop there.
The introduction of immunoglobulin is also permissible in the first 72 hours after childbirth, at the birth of a Rh-positive baby, if previously immunization was not carried out.
If antibodies nevertheless appear before 28 weeks, and are growing, the pregnant woman will be sent for a more in-depth examination to determine the degree of Rh-conflict, treatment and, if necessary, emergency delivery.
How to know your risk
Today, the only measure for predicting a conflict recommended and funded by the Ministry of Health is a blood test for anti-rhesus antibodies.
However, there is another option for solving the “problem”.
Already from 10 (with singleton) and 12 weeks (with multiple) pregnancy, it is possible to determine the Rh of the fetus by the mother’s blood.
The study does not require special preparation and there are practically no contraindications. And its reliability is 99%.
The analysis is actively used in the USA, Japan and most of Western Europe. And during its existence, it has established itself as absolutely safe and highly effective.