Prenatal Screening

Today every pregnant woman is recommended to undergo prenatal screening. This study identifies women at high risk of developing a child with chromosomal pathologies, primarily Down's syndrome. It is very important to understand that the results of this analysis are not the final diagnosis.

Women in the risk group need to undergo an additional examination. In this case, amniocentesis or a chorionic villus biopsy is done. However, one should know that these manipulations sometimes lead to the termination of pregnancy.

In general, prenatal screening is worthwhile only for those women who are exactly sure that they will not give birth to a baby with chromosomal abnormalities. At their high probability they are ready to carry out dangerous manipulations, and at confirmation of the diagnosis - to interrupt pregnancy. If this is not the case, the patient will simply waste her money.

Prenatal screening of the first trimester consists of ultrasound and the determination in the blood of a level of special markers. The study is carried out from 10 to 13 weeks. First, an ultrasound is performed, at which the doctor examines the fetus for pathologies and measures the dimensions needed to calculate the risk.

It is advisable to donate blood on PAPP-A and free β-hCG the next day. The analysis is performed on an empty stomach in the morning. Based on the results of ultrasound and a double test, the risk is calculated that the Edwards and Down syndromes are present in the fetus.

Prenatal biochemical screening is also carried out in the 2nd trimester. The recommended time is from 16 to 18 weeks. During this period, the blood is given for free estriol, AFP, total hCG or free β-hCG. These indicators calculate the risks of neural tube defects, Down syndrome and Edwards syndrome in the fetus.

Here it should be noted that even if a woman is small, it still does not exclude the birth of a baby with a pathology. Just in this case, the probability is extremely small and neglected.

Other factors are taken into account when calculating risks. These include IVF, smoking, diabetes, race, weight, medications taken, age, the presence of pregnancies with genetic pathologies. It should be noted that the older the woman, the higher the probability of chromosomal abnormalities in the child. In order for the result to be reliable, it is necessary to know the time exactly.

In the form of the result, it is usually not the absolute value of the indicator that is dependent on the test system used, but Mom (the multiplicity of the mean value at the same time). Its value should be from 0.5 to 2. In normal pregnancy, the figure is 2.5, and for a multiple pregnancy it is 3.5.

If the patient undergoes prenatal skinning, then deviations from the norm of certain indicators can be suspected of certain pathologies. Thus, ACE is elevated in renal syndrome, tetralogy of Fallot, hydrocephalus, defects in skin, abdominal wall and neural tube.

If against a background of its low value hCG is increased, it is possible to suspect Down's syndrome. Especially it should alarm at the age of the patient more than 30 years, and it does not matter how many pregnancies were before.

Risk factors for chromosomal abnormalities:

• Irradiation of even one of the spouses before conception;
• Viral infections (toxoplasmosis, rubella, hepatitis);
• Use of antitumor drugs by a woman before or during pregnancy;
• Monogenic diseases in the immediate family;
• More than 2 miscarriages in the early stages;
• The family already had a fetus or a child with chromosomal illnesses ;
• Age more than 35.

So, prenatal screening is desirable for all women who are expecting a baby. However, it is very important to understand that the results are not the final diagnosis, but only an occasion to undergo a more serious examination. If a woman does not interrupt pregnancy while confirming chromosomal abnormalities in a child, then she does not need to undergo screening. Since doctors besides abortion can not offer anything, there are no methods of correcting this pathology today.