Genetic testing in pregnancy

Genetic analysis during pregnancy is a must, this is the most reliable way to calculate the probability of developing pathologies and hereditary defects in the future child.

The test should also be done if:

1. Conception takes a long time or the pregnancy ends in miscarriage. The reason may be defects in the chromosomes of the father and mother.
2. If the parents are over 35 years old. In this case, the probability of mutations and chromosomal failures increases significantly.
3. A pregnant woman may also be referred for genetic testing by a doctor, based on her medical history:
   • The expectant mother or father has serious hereditary diseases.
   • The family already has children with chromosome abnormalities.
   • The expectant mother is over 30-35 years old.
   • If the expectant mother took serious medications, narcotic substances, or alcoholic beverages in the first half of pregnancy.
4. Another indication for genetic testing may be a suspicion of a frozen pregnancy during an ultrasound examination.
5. If there are changes in biochemical tests, you will also need to undergo genetic analysis.

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Down's test during pregnancy

It is necessary to take a Down's test during pregnancy, but it is still better to do such a test before planning a child in order to calculate the probability of a child with abnormalities being born to a particular couple. The probability that a young couple will have a child with Down's syndrome is also not excluded.

The most accurate result is given by a combined diagnostic method consisting of ultrasound diagnostics, where the thickness of the collar zone is assessed and special markers are detected in the blood serum. It is best to diagnose Down syndrome and other chromosomal abnormalities at 16-18 weeks of gestation. At this term, the so-called "triple test" is done, and only in one percent of cases does it give a false result. But it is better to take several tests - this way you can get the most accurate result. So, with a positive test for Down syndrome, an additional study of the amniotic fluid is carried out (but only if the expectant mother has no contraindications to amniocentesis ).

Do not despair if the test result is positive – the possibility of a diagnostic error cannot be ruled out. In this case, it is better to repeat the diagnosis in one or two weeks and additionally consult a geneticist.

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AFP Analysis During Pregnancy

AFP analysis during pregnancy also falls into the category of mandatory tests. Pregnant women are prescribed this test to exclude the possibility of the baby developing chromosomal abnormalities, neural tube defects, as well as abnormalities of internal organs and limbs. It is advisable to conduct diagnostics between 12-20 weeks, but the most accurate information can be obtained at 14-15 weeks.

The fetus's body begins to produce AFP from the 5th week, and accordingly, with each subsequent week, the percentage of AFP in the mother's blood increases, reaching a maximum at 32-34 weeks. The norm for the AFP indicator is 0.5-2.5 MoM. If the indicator is higher than the norm, this may indicate:

• An error in specifying the gestational age.
• There is a multiple pregnancy.
• Kidney problems.
• Umbilical hernia in the fetus.
• Anomalies of the nerve column.
• Abdominal wall anomalies.
• Other physiological defects.

If the AFP level is low, there is a high probability of Down syndrome, hydrocephalus, trisomy, hydatidiform mole, other chromosomal abnormalities, developmental delay and intrauterine death of the fetus.

You shouldn't rely entirely on the AFP blood levels; you can't make a full diagnosis based on the test results, so don't despair or get upset. With certain deviations from the norm, healthy children are born in more than 90% of cases.

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PAPP-A Analysis During Pregnancy

The PAPP-A analysis during pregnancy is carried out in the first trimester in order to identify the risk of having a child with chromosomal abnormalities. The level of PAPP-A in the mother's blood decreases in the case of chromosomal abnormalities, the threat of miscarriage, and a frozen pregnancy. The analysis is carried out starting from the 8th week, but the most optimal time is 12-14 weeks. After this term, the reliability of the result is significantly reduced. The most accurate result can be obtained if a comprehensive examination is carried out - an analysis of the hCG level, the PAPP-A level, and an examination of the collar zone of the fetus using an ultrasound machine.

The analysis of RAPP-A during pregnancy is prescribed to pregnant women who:

• Have a history of complicated pregnancy.
• Are over 35 years old.
• Have a history of two or more spontaneous abortions.
• Have a history of viral and infectious diseases suffered before conception or in the early stages of pregnancy.
• There is a child with chromosomal abnormalities in the family.
• They have severe hereditary pathologies in their family.
• Before pregnancy, the parents were exposed to radiation.

An increase in the PAPP-A content indicates a high risk of chromosomal abnormalities in the future baby (abnormalities in the 21st and 18th pairs of chromosomes and other abnormalities), a high probability of pregnancy loss and spontaneous abortion.

Genetic analysis during pregnancy helps to diagnose pathologies in the fetus at an early stage, and timely initiation of treatment helps to preserve the pregnancy and the health of the baby.

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