As people's awareness of eugenics and eugenics increases, pregnant women pay more and more attention to prenatal screening. During the prenatal examination, ultrasound testing is essential. At present, the number of prenatal check-ups in pregnant women increases with the increase of gestational week, but with the development of medicine, fetal Down's screening and deformity examinations are moving more and more forward. So what is the significance of Down's screening?
Traditional Down's screening
Down's syndrome is currently unpreventable, and even more untreatable. The simple and easy method is to conduct prenatal screening and clarify the diagnosis. In fact, regardless of age and whether there are high-risk factors, all expectant mothers should undergo Down screening, except for expectant mothers who need to have direct prenatal diagnosis.
The current gestational week range for Down’s screening is 15-20 weeks of pregnancy, and Down’s screening in the early stages of pregnancy (11-13 weeks + 6) has not been fully popularized. So the question is, is it a bit late to find the problem in the middle of pregnancy? Are there any earlier predictive indicators?
ultrasound detection is indispensable
From the perspective of medical development, some indicators that appear in the early pregnancy have a greater effect as evaluating maternal and fetal risk factors. Ultrasound detection, such as nasal bone defects or dysplasia, strong echoes of the intestinal tract, thickening of the transparent layer behind the neck, and strong echoes in the heart... These can show relevant hints, so ultrasound detection is indispensable.
NT is a major breakthrough in prenatal ultrasound diagnosis
The measurement of the neck transparency layer should be between 11-13+6 weeks. Since the changes in the transparent layer of the neck are closely related to the gestational week, strict regulations are made for measuring the gestational week of the transparent layer of the neck. The abnormal thickening of fetal NT at 11-13 weeks + 6 is a symptom of chromosomal abnormalities, various fetal malformations and genetic syndromes. Although the cause is not clear, it may be related to many factors such as chromosomal abnormalities and early fetal heart failure. Therefore, early examinations can be used as a reference for data to determine whether the fetus is healthy or not.
Pregnant women do not have to be anxious about the simple increase in the number
Many pregnant women will find that some data are high or low during prenatal examinations and are nervous because of the increase in NT value and consult everywhere. In most cases, doctors cannot determine whether the fetus is abnormal, but need to know through further invasive screening. In fact, the phenomenon of subcutaneous hydrops on the back of the fetus' neck does not mean that the fetus becomes abnormal, but as its thickness increases, the risk of chromosomal abnormalities is that the risk of Down syndrome will increase.
Generally speaking, according to the existing data, during the process of fetal malformation screening in the middle of pregnancy, if the NF behind the neck is greater than or equal to 6mm, abnormalities must be considered. On the one hand, the detection rate can be improved, and on the other hand, the risk of unnecessary and invasive prenatal diagnosis can be reduced. Of course, in addition to being related to fetal chromosomal abnormalities, it may also be related to other factors, such as fetal anemia and congenital infection. Heart abnormalities may lead to NT thickening. Therefore, once NT thickening is found, it is necessary to consider comprehensively, and an invasive prenatal diagnosis should be conducted; if there are any concerns, non-invasive genetic testing can be chosen.
At the same time, do not ignore other indicators
From some international and domestic consensus and guidelines, the thickening of NT can be used as an independent reference factor for prenatal diagnosis without other structural abnormalities. For example, if the nasal bone is missing or underdeveloped, the support for the risk of Down syndrome is far greater than other soft indicators.
With the improvement of medical skills, the methods and means of prenatal examinations are also increasing, making them more accurate and non-invasive, but prenatal examinations are not omnipotent, and some special situations are still not easy to be discovered or cannot be examined. Therefore, if there is a problem with the fetus, expectant mothers should not blame the loopholes in the prenatal examination. It is recommended that expectant mothers have a good daily routine checkup and eat a balanced diet. As long as they are healthy and good, the baby will definitely be healthy and safe!
