Screening is what?

Each married couple dreams of producing a strong and healthy baby. But, to the great regret, no one is immune from the fact that child development can take place with problems due to genetic abnormalities.

During pregnancy the future mother gives tests, undergoes many different studies, as well as monitoring the development of the fetus and preparing 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 a routine study using 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 disorder, it is possible, but only after carrying out combined genetic screening is a complex of measures and research. They are held before delivery.

Screening - what is it?

The word means "sifting", if you translate it from English. Screening ultrasound is carried out for 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 of activities that take place before birth 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 such a study can not be called the basis for the diagnosis. After all, screening is just an opportunity to establish the degree of risk of a chromosomal disease. If it is high, prospective mothers are assigned invasive cytogenetic studies.

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

The first stage of the "screening" procedure is an ultrasound 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 no visible pathologies are 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 chromosomal diseases 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. The ratio and concentration of specific proteins and marker substances are also evaluated.

The third stage is the calculation of the risk of obtaining chromosome pathologies 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 patient gets 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 is already accurate to 100% can determine the presence of any chromosomal abnormalities.