Prenatal screening

Today, genetic studies are very important, both for assessing the risk of certain diseases (genetic screening) and for diagnosis.
In what cases is a genetic study carried out in a reproductive clinic:

• it is difficult to differentiate sex during the neonatal period;
• there is a lag in physical and / or mental development;
• primary amenorrhea (absence of menses);
• infertility;
• frequent abortions;
• For the purpose of diagnosing the genetic pathology of the fetus during pregnancy.

One of the most common methods of genetic screening is: prenatal (during pregnancy) screening.
Prenatal screening is done in the first and second trimesters of pregnancy. Taking into account specific biochemical markers, ultrasound data and maternal age, the risk of fetal chromosomal abnormalities (Down syndrome, Edwards syndrome, Patau syndrome) and neural tube defects is assessed.

None of the screening tests has diagnostic value, that is, they are not used to make a diagnosis. Based on the results, the geneticist determines whether the patient needs further diagnostic tests.
As for the methods of genetic diagnostics (both during pregnancy and in children, non-pregnant women, men), it is used to diagnose either genetic (caused by a change in one gene) or chromosomal (change in the number or structure of chromosomes) diseases.

Train screening. Recently, pregnancy screening has become quite popular, which is also recommended by such reputable organizations as the American College of Medical Genetics, the American College of Obstetricians and Gynecologists, the Society for Maternal and Fetal Medicine, and others. If the family history is aggravated by a genetic disease, or there is a consanguineous marriage, or the patient wants to know which genetic mutation of the disease he is a carrier of, then carrier screening is used. The mentioned study also determines the risk of developing a genetic disease in the offspring, and preimplantation genetic diagnosis can also be offered.

Cytogenetic study – the number and structure of an individual’s chromosomes are assessed. Accordingly, this research method makes it possible to detect quantitative and large structural changes in chromosomes.

Preimplantation genetic testing – genetic testing is carried out in case of in vitro fertilization. As a result of the study, the presence of chromosomal diseases and genetic diseases in the embryo is assessed. After such a study, only healthy embryos are transferred to the uterus.
The method of genetic research is selected individually, taking into account the patient’s history, diagnosis and reproductive plans.

Therefore, genetic testing should be planned by the attending physician and/or geneticist. It is very important that the patient is fully informed about the possibilities of the method (which diseases are screened/diagnosed) before the examination.