The concept of prenatal screening test
According to research by the World Health Organization (WHO), the rate of birth defects in newborns is 1.73%, meaning that every year, the world has about 8 million babies born with at least one birth defect. born. In Vietnam, according to statistics of the Ministry of Health, every year, around 1.5 million babies are born in the country, of which: about 1,400-1,800 children with Down syndrome (Trisomy 21); 200-250 children with Edwards syndrome (Trisomy 18); 1,000-1,500 children with neural tube defects; about 2,200 children with Thalassemia disease (congenital hemolytic disease) are serious and there are many genetic diseases, other birth defects. Many causes lead to such conditions as chromosomal abnormalities, gene disorders, metabolic disorders, etc. In particular, many defects can be detected and intervened early through prenatal and neonatal screening. Therefore, prenatal screening is necessary to screen and help identify the risk of birth defects from the unborn child.
One of prenatal screening methods being applied advanced in our country today is a prenatal genetic diagnosis noninvasive NIPT.
Other methods such as amniocentesis invasive, villus … can cause miscarriage with 1/500, with this technical analysis uses only room from 7-10 ml of blood from pregnant women to consider mutation screening chromosome number and early detection of congenital malformations to the fetus. This method can be done right from the 10th week of pregnancy, for accurate results up to 99.98%. So we need to find out whether screening noninvasive prenatal NIPT is how Light:
First we need to understand what nipt is ?
Nipt is a pre – invasive test that does not invade the most advanced, nipt recognized by fda&clia recognition of the condition of testing and accuracy of the results of thường syndrome. The accuracy of 99, 9%, with only the mother’ s blood without having to interfere with the fetus. This type of blood contains and mother’ s freedom and the child, with modern technology, nipt can analyze the abnormalities of the chromosomes, such as too much or too little chromosome in the fetus.
Which pregnant women do nipt tests?
All pregnant mothers should carry out screening before the nipt. Especially the high – risk pregnant mothers:
– Pregnant woman over 35.
– Pegnant pregnant women have multiple miscarriages or dead pregnancies, the first one is deformed.
– Tere’ s an abnormal ultrasound result, gáy on 3. 0mm. Ultrasound sees short – nosed bones, slow .. bone.
– Double test / triple test and ultrasound results.
– The history of genetic disease from the family of (Birth parents, Grandparents, husband) related to chromosome mutations.
– Do the ivf technique or set
– Pregnant women and virus when pregnant
– Pregnant women work in the environment in contact with chemicals, radioactive substances, high doses of toxic substances.
– Pregnant women have abnormal signs such as masonry, hypertension, vaginal bleeding, excessive fluids or too little, stomach…
However, there are a number of non – performing cases that are: patient blood transfusion, organ transplant, stem cell treatment, clotting treatment with heparin within a year from the day of the test and the dual – disappearing pregnancy syndrome (vanishing twin)
The advantage of the nipt method
Compared to classical methods, nipt tests for more accurate results are limited to the maximum ratio of pregnant pregnant mothers to the risk of accessing hidden capital.
The advantages of this approach are:
– It can be done from very early: the 10th pregnancy
– Not to eat
– Absolute safety: tests on mother’ s blood, from 7 – 10 ml.
– The accuracy of 99, 9%
– Control and detection of syndrome related to children’ s chromosomes in common.
– Quickly: there’ s only five – after 7 days
What does the nipt test mean?
There are three nipt results
- Positive/high risk/deflection detection: These results mean the fetus is capable of carrying the disorder chromosome surveyed => Your doctor will advise you about the results and the direction you consider service-invasive testing such as amniocentesis or biopsy in other to confirm the diagnosis.
- Negative / low risk / not detected deviation multiples: Fetal your safe for the abnormal chromosome, but you still have to monitor any prenatal care ultrasound to monitor the morphology of the fetus.
- Cannot conclude/no result/suspected deviations: Test results can not be concluded or may not be on a blood sample analysis => In this case due to fetal DNA is too low, the need to conduct the 2nd sampling Since fetal DNA increases with some weeks pregnant should take blood 2nd time will gain more freedom of fetal DNA than to analyze.