Prenatal diagnosis

Prenatal diagnosis represents a complex of prenatal inspection. The main objective, at the same time, puts identification at a stage of pre-natal development of the child of various pathologies.

What prenatal diagnosis is applied to

Thanks to prenatal diagnosis of hereditary diseases, it is possible to find the following disturbances in a fruit:

• Down syndrome;
• Edwards's syndrome;
• Disturbances in development of heart, etc.

Prenatal diagnosis of hereditary diseases plays a crucial role in destiny of future child. On the basis of the obtained data, parents, together with the doctor, make the decision on that, pregnancy will be interrupted or not. At the favorable forecast of doctors, rehabilitation of future child can be carried out.

Prenatal diagnosis also is also definition of paternity according to the genetic expertize which is carried out on early durations of gestation and sex determination of the child.

Main methods of prenatal diagnosis

In modern conditions, in prenatal diagnosis various technologies are applied. Reliability degree, opportunity levels at them various.

There are two main groups of prenatal diagnosis:

1. Noninvasive;

2. Invasive.

Noninvasive methods, or still them call low-invasive, do not provide surgical intervention and traumatizing mother and a fruit. Such procedures are harmless, and can recommend them to all pregnant women, without exception.

Invasive prenatal diagnosis assumes surgical intervention (invasion) into the woman's organism (a cavity of her uterus).

Invasive prenatal diagnosis is unsafe for mother and a fruit therefore it is appointed by doctors only in extreme cases when there are serious fears for health of future child.

The pregnant woman needs to visit planned ultrasonography surely, it will allow to exclude or, on the contrary, to confirm need for carrying out invasive prenatal diagnosis.

The procedures relating to noninvasive prenatal diagnosis

The following belongs to methods of noninvasive prenatal diagnosis:

• Ultrasonic prenatal screening (observation in dynamics of fetation);
• Prenatal screening of serum factors of blood of mother.

Prenatal screening – no other than the usual ultrasonography shown to all pregnant women. The obligatory periods of passing of ultrasonography are the following durations of gestation:

1. 11 – 13 weeks;

2. 22 – 25 weeks.

Prenatal screening provides diagnosis of a condition of a fruit and mother's organism. The sensor (transdyuser) is installed on the surface of a stomach of the woman, it lets out sound waves. These waves are also caught by the sensor, transferring them to the monitor screen. On early durations of gestation other kind of prenatal screening of ultrasonography can be used. It is a transvaginal way at which the sensor is entered into a vagina of the pregnant woman.

Prenatal screening gives the chance to define on different durations of gestation a number of deviations in fetation:

1. Inborn heart diseases, kidneys, liver, intestines, extremities, etc.;

2. Symptoms of a Down syndrome - to 12 week durations of gestation.

Besides, prenatal screening of ultrasonography defines development of the pregnancy:

• Uterine or extrauterine;
• Quantity of fruits in a uterus;
• Age of a fruit (duration of gestation);
• Provision of a fruit (pelvic or head presentation);
• Lag in fetation;
• Heartbeat (its character);
• Sex of the child;
• State and arrangement of a placenta;
• Assessment of amniotic waters;
• Condition of a blood-groove in placenta vessels;
• Uterus tone.

Thus, prenatal screening helps to find out whether normally there takes place pregnancy. For example, having defined a condition of a tone of uterine muscles, it is possible to establish threat of abortion (abortion) and to take urgent measures for elimination of this problem.

Prenatal screening of maternal serum factors assumes a blood analysis, the pregnant woman taken from a vein. The best term for the analysis is the period from the 15th to the 20th week of pregnancy.

Blood serum of the woman is investigated according to contents in it certain substances:

• Alpha-fetoprotein (AFP);
• Not the Conjugated Estriol (CE);
• Chorionic Gonadotrophin (CG).

Such way of prenatal screening possesses a fine precision. But, in certain cases, tests can give false positive or false-negative answers. Then appoint additional procedures for prenatal diagnosis of hereditary diseases. It can be prenatal screening (ultrasonography) or kinds of invasive prenatal diagnosis.
The procedures relating to invasive prenatal diagnosis

For prenatal diagnosis of hereditary diseases and other disturbances in fetation, in case of the decision on use of invasive methods of prenatal diagnosis, such procedures are used:

• Kordotsentez (capture of test and research of umbilical blood);
• Chorion biopsy (studying of structure of cells which are a basis for formation of a placenta);
• Amniocentesis (capture and research of amniotic waters of mother);
• Platsentotsentez (identification of negative effects of the infection transferred to the pregnancy period).

Advantages of invasive prenatal diagnosis are 100% a guarantee of result and its speed. Besides, invasive prenatal diagnosis can be used on the earliest durations of gestation.

Thus, if there is a suspicion on any deviation of development of pregnancy and health of the child, thanks to a way of prenatal diagnosis of hereditary diseases, it is possible to draw exact conclusions. Therefore, doctors and parents are given a real opportunity to make the specific decision in further actions:

1. To leave the child;

2. To make abortion.

At the decision of parents, despite pathology, to leave pregnancy, thanks to early prenatal diagnosis of hereditary diseases, at the disposal of doctors there is time for the greatest possible correction of pregnancy and treatment of a fruit in a womb.

If it is about abortion, this procedure is morally and physically postponed easier on the early term on which deviations in development were revealed.