Prenatal diagnosis is a set of pre-natal examinations. The main purpose in this case is put on the identification of fetal stages of child development of various pathologies.
Why use prenatal diagnosis
Thanks to prenatal diagnosis of hereditary diseases, can be detected in the fetus following violations:
- Down's syndrome;
- Edwards syndrome;
- Abnormalities in heart development, and others.
That prenatal diagnosis of hereditary diseases plays a crucial role in the fate of the unborn child. Based on these data, parents, together with the doctor, make a decision about a pregnancy is terminated or not. With a favorable prognosis doctors, it can be carried out rehabilitation of the child.
Prenatal diagnosis is also the determination of paternity according to the genetic examination, conducted in early pregnancy, and determining the sex of the child.
The main methods of prenatal diagnosis
In modern conditions, prenatal diagnosis used different technologies. The reliability levels have different capabilities.
There are two main groups of prenatal diagnosis:
Non-invasive or minimally invasive yet they are called, do not include surgery or injury to the mother and fetus. Such procedures are not dangerous, and may recommend that all pregnant women, without exception.
Invasive prenatal diagnosis involves surgery (invasion) in a woman's body (its cavity of the uterus).
Invasive prenatal diagnosis is not safe for the mother and the fetus, so the doctors appointed only in extreme cases where there are serious concerns for the health of the unborn child.
Routine ultrasound examination of a pregnant woman needs to go to be sure, it would eliminate or, alternatively, confirm the need for invasive prenatal diagnosis.
Procedures related to noninvasive prenatal diagnosis
The methods of non-invasive prenatal diagnosis include the following:
- Ultrasound prenatal screening (surveillance in the dynamics of the development of the fetus);
- Prenatal screening maternal blood serum factors.
Prenatal screening - is not nothing but a normal ultrasound, shown to all pregnant women. Compulsory period following the passage of ultrasound are the stages of pregnancy:
1. 11 - 13 weeks;
2. 22 - 25 weeks.
Prenatal screening involves diagnosis of the fetus and the mother's body. A sensor (transducer) is installed on the surface of the abdomen of women, it emits sound waves. These waves and picks up the sensor, bringing them to the screen. In the early stages of pregnancy can be used another type of prenatal ultrasound screening. This transvaginal method in which the probe is inserted into the vagina of a pregnant woman.
Prenatal screening makes it possible to determine at different stages of pregnancy, a number of deviations in the development of the fetus:
1. Congenital malformations of the heart, kidneys, liver, intestines, limbs, etc .;
2. The symptoms of Down syndrome - up to 12 weeks of pregnancy.
In addition, prenatal screening ultrasound determines the development of the pregnancy:
- Uterine or ectopic;
- The number of fetuses in the womb;
- Age of the fetus (gestational age);
- The position of the fetus (pelvic or cephalic presentation);
- The lag in the development of the fetus;
- Palpitations (his character);
- Sex of the child;
- The condition and location of the placenta;
- Assessment of amniotic fluid;
- Status of blood flow in vessels of the placenta;
- The tone of the uterus.
Thus, prenatal screening helps to find out whether the pregnancy is normal. For example, determine the status of the uterine muscle tone, you can set the threat of termination of pregnancy (abortion) and to take urgent measures to address this problem.
Prenatal screening of maternal serum factors suggests a study of blood taken from a vein of a pregnant woman. The best period for the analysis is the period from the 15th to 20th week of pregnancy.
Serum women examined for its content of certain substances:
- Alpha-fetoprotein (AFP);
- Unconjugated estriol (NE);
- Human chorionic gonadotropin (hCG).
This method of prenatal screening has a high degree of accuracy. However, in some cases, tests may provide false positive or false negative responses. Then prescribe additional procedures for prenatal diagnosis of hereditary diseases. It may be prenatal screening (ultrasound) or species invasive prenatal diagnosis.
Procedures related to invasive prenatal diagnosis
For prenatal diagnosis of hereditary diseases and other disorders in the development of the fetus, in the case of a decision on the use of invasive prenatal diagnosis, such procedures are used:
- Cordocentesis (sampling and testing of umbilical cord blood);
- Chorionic villus sampling (study of the composition of cells, which are the basis for the formation of the placenta);
- Amniocentesis (taking amniocentesis and mother);
- Platsentotsentez (identifying the negative effects of infection in pregnancy transferred).
The benefits of invasive prenatal diagnosis are 100% guaranteed result and speed. In addition, invasive prenatal diagnosis can be used in the very early stages of pregnancy.
Thus, if there is a suspicion of any deviation in the development of the pregnancy and the child's health, due to the method of prenatal diagnosis of hereditary diseases, can draw accurate conclusions. Therefore, doctors and parents to provide a real opportunity to take a concrete decision for further action:
1. Leave the child;
2. Make abortion.
In addressing the parents, in spite of pathology, pregnancy leave, thanks to early prenatal diagnosis of hereditary diseases, doctors have the time available for the maximum possible correction of pregnancy and treatment of the fetus inside the womb.
If we are talking about abortion, the procedure is obsolete and it is easily transferred in early pregnancy, which revealed deviations in development.