The difference between non invasive, tang sieving, and sheep wearing

In general, non-invasive and sheep wear are follow-up tests done when the results of Tang screening are at high risk.

Tang sieve is a screening for children with Down syndrome, which is a chromosomal abnormality.

Non-invasive is a blood test that shows the probability of Down's disease.

Amniocentesis is an amniocentesis that can determine whether it is a Down's baby, but there is a risk of miscarriage and other surgical risks.

In addition, there are also problems with the babies born with low risk of Tang Sieving. Because it's inherently a matter of probability.

Tang Sieve is based on the pregnant woman's gestational age, age, weight, hormone level reference value, the accuracy rate is only about 60% to 70%.

Non-invasive detection for 21, 18, 13, no risk, accuracy can reach more than 99%.

Sheep wear is a diagnosis, and the accuracy rate can reach more than 99%, but there is a certain risk of miscarriage.

Amniocentesis is known.

1. Pregnant women can take amniotic fluid after 16 weeks of pregnancy for fetal parental identification, and the fetus is relatively stable at this stage and the risk is relatively low. Just aspirate 2-3 ml of amniotic fluid.

Non-invasive DNA 1, pregnant women have a pregnancy cycle of 8-26 weeks, and the best internal extraction is 11-26 weeks. Both men and women need to take more than 5ml of venous blood.

2. When the pregnant woman is 11-26 weeks pregnant, the DNA content of the fetus contained in the blood of the pregnant woman reaches the detection standard, and the DNA data of the fetus can be detected by a high-throughput sequencer, and compared with the father's DNA to determine whether the fetus and the man have a parent-child relationship.

There are still errors in the theory of non-invasive DNA, and as a clinical verification of new technology methods, the results are for reference only, not for diagnosis, and sheep wear can be used as a diagnostic result, generally if the doctor recommends that you continue to do sheep wear, it means that you are still at high risk and need to do sheep wear for further examination.

Because the accuracy of Down screening is only about 70%, the diagnosis and treatment conclusion of non-invasive DNA and amniocentesis will be more accurate than that of Down's screening. The non-invasive accuracy of trisomy 21 is 99%, and the sheep wear is almost 100%. Therefore, if a pregnant mother with a high risk of screening for Down syndrome, in order to avoid wrongful killing of the poor little life, it is necessary to do non-invasive DNA or amniocentesis.

Down's screening for high risk and then non-invasive testing can be partially based on. Down's screening is high-risk, many fetuses are fine, only a small percentage of fetuses are Down's babies, and the likelihood of having a Down's baby is not very high.

If you are concerned about sheep wearing, due to the high risk of only trisomy 21, you can also do non-invasive genetic testing first, because the accuracy of non-invasive DNA testing for trisomy 21 is 99%. If the non-invasive DNA or high risk, you must do sheep wear, indicating that the baby has a high probability of giving birth to a Down's baby As a mother of two children, I share my parenting experience with you based on my own work experience! According to my knowledge, it is very likely that non-invasive is not so risky or risk-free!

However, if amniocentesis is done, it will be much more risky than non-invasive.

Actually choose which one to do, or follow the advice given to you by your pregnancy tester, usually the doctor will also recommend a very small risk to do this for you! You only need to release the stress psychological state, many people Tang screening high-risk examination, and then all of them have been checked in this regard, before it is clear that the baby's physical health growth and development are healthy. Non-invasive DNA is only a screening experiment, which can not 100% clear the abnormality of the fetus, and the chromosomal mutation of twins and chimeras is a blind spot, and it is only accurate for trisomy and other diseases, and amniocentesis is also necessary to carry out amniocentesis in the process.

The best time for amniocentesis is 18-24 weeks pregnant. At this moment, the fetus is small, the amniotic fluid is relatively more, and there is a wide amniotic fluid belt around the fetus, when the amniotic fluid is extracted by needle puncture, it is not easy to puncture the fetus, and the extraction of 20ml of amniotic fluid only accounts for 1 20-1 12 of the total amniotic fluid production, which is not easy to cause the uterine body to shrink sharply and miscarriage. In addition, at this stage, the glamorous somatic cells in the amniotic fluid account for a relatively large proportion, and the cell culture medium has a high survival rate, which can be used for producers, coloring, fetal chromosome karyotype analysis, sex chromosome genetic disease diagnosis and gender judgment, and amniotic fluid somatic cell DNA can also be used to confirm genetic diseases and metabolic diseases.

Measuring the high level of alpha-fetoprotein in amniotic fluid can also confirm the diagnosis of fetal open neural tube defects.

It is better to do non-invasive high-risk Tang screening; Amniocentesis may cause the risk of baby miscarriage and infection, and non-invasive DNA testing is not particularly traumatic, mainly to draw the peripheral blood of pregnant women.

Tang sieve high-risk should be done sheep wearing, because it is more efficient, clearer and more accurate if it is done sheep wearing.

Amniocentesis is necessary. Because amniocentesis can directly detect fetal cells, it is confirmatory, while non-invasive DNA testing is a spot check and may miss the diagnosis.

Amniocentesis should be chosen, amniocentesis is very accurate, and amniocentesis is cheaper than non-invasive DNA.

It can be selected according to the physical condition, and it is better to choose amniocentesis because the accuracy of this test is a little higher.

Amniocentesis is an option, but be sure to go to a professional institution and be sure to follow the advice of a professional doctor