Screening is what?

Each married couple dreams ofproduce a strong and healthy baby. But, to the great regret, no one is immune from the fact that the child's development can go through with problems due to genetic anomalies.

During pregnancy, the future mother gives tests,there are many different studies, as well as monitoring the development of the fetus and the preparation for childbirth. But, in spite of all this, children with Down's syndrome are constantly born in the country. Naturally, every such case is an incredible grief and a complete surprise for the parents.

This is due to the fact that an ordinary study withUsing ultrasound can not determine this syndrome and the other chromosomal abnormalities. For example, with the help of ultrasound it is possible to evaluate only the external data of the baby and to identify certain congenital malformations in development. But most of the children born with Down syndrome and Edwards have no external anomalies. With an accuracy to find out that the fetus has a chromosomal abnormality it is possible, but only after carrying out the combined genetic screening is a complex of measures and researches. They are held before delivery.

Screening - what is it?

The word means "sifting", if we translateits from English. Screening ultrasound is carried out almost all future mothers, even if the pregnancy is completely normal. Do it from 11-13 weeks of pregnancy.

Combined genetic screening is a series ofactivities that take place before delivery and are aimed at diagnosing genetic abnormalities. It includes ultrasound and biochemical examination, as well as an individual calculation of the risk of bearing a child with a chromosomal pathology.

It is important to note that the results of thisresearch can not be called the basis for diagnosis. After all, screening is just an opportunity to establish the degree of risk of a chromosomal disease. If it is high, future moms are assigned invasive cytogenetic studies.

How is the screening of pregnant women? Let's consider more

The first stage of the "screening" procedure isultrasound examination of the fetus. In the course of his assessment of the compliance of the size of the baby with the term of pregnancy, the general condition of the embryo, some pronounced malformations in development and so on. That is what can be seen externally. But it is worth noting that even if visible pathologies are not observed, this does not mean that there are none.

For example, in children suffering from Down's syndrome, only in half of the cases can be seen visual abnormalities.

A more accurate result of the presence of chromosomaldiseases can be obtained only after the second stage of screening - biochemical - is completed. Here, the blood of a prospective mother is examined for the presence of a specific substance that is excreted by the placenta. Also, the ratio and concentration in blood of specific proteins and marker substances are evaluated.

The third stage is the calculation of the risk of obtaining chromosomalpathologies with the help of special computer programs. In addition to previous results, indicators such as the age and weight of the mother, the length of pregnancy, the presence of bad habits, genetic diseases and even ethnicity are also used. After the computer processes the information received, the doctor can draw a conclusion about how high the risk of having a child with genetic diseases.

If he is at a low level, the patientgets rid of the need to re-conduct any studies, followed by routine observation. When the level is average, another screening is carried out in the second trimester. When the risk is high, a prenatal diagnosis program is prescribed. It can determine the presence of any chromosomal abnormalities with an accuracy of 100%.