Do I need to do Down syndrome screening after doing NT?

Various examinations need to be done after pregnancy. I believe every pregnant mother knows about them, but many people are not very sure about the examination items. Today we will introduce them. Generally, at 12 weeks of pregnancy, you must go to the hospital for an NT examination. Although many people know about this new item, NT examination, they know nothing about the content of the examination. So, can the NT test still be used as a screening test for Down syndrome?

In short, the NT examination is an effective medical imaging method for detecting abnormalities in children's development at an early stage. It mainly relies on the accurate measurement of the thickness of the fetal posterior tibial translucency to identify the probability of a deformed baby. Generally speaking, the thicker the posterior tibial translucency, the greater the probability of fetal abnormalities. If the measured value is less than 2.5mm, it means that the child's development is normal. If the value exceeds 2.5mm, further examination is needed.

Therefore, we can see that the NT test is actually a way to identify the probability of a malformed baby, and the Down syndrome screening test is also a way to check for baby malformations. So, can the NT done during pregnancy still be used as a Down syndrome screening? For this type of prenatal examination items, pregnant mothers should have a clear understanding before doing it.

First of all, let's understand what are the differences in Nt's regular maintenance in Dandong?

Generally, the best time to do a NT test is around 11 to 13 weeks of pregnancy. If the fetus is too small, some defects may not occur before 11 weeks and may be missed. If the test is done after 13 weeks, too much blood may be absorbed by the developing lymphatic system of the fetus. Moreover, after 14 weeks of pregnancy, the fetus will show signs of changes, which increases the difficulty of accurate measurement and the success rate will also decrease by 90%. Therefore, the NT test must be done within the prescribed time period, neither too late nor too early.

Of course, the NT test is not 100% accurate. Although it can detect some deformities, it cannot be said that deformities are completely unlikely to occur. Even if the NT values ​​measured are normal, there is still a probability that the baby will be deformed after birth. Of course, this probability is relatively small. If the NT test value is abnormal, further examination is needed. Therefore, the NT test is not the only way to identify malformed babies, nor can it detect all malformations.

Although Down syndrome screening and NT are both used to detect fetal deformities, they are also very different. The main purpose of Down syndrome screening is to check whether the fetus has Down syndrome. Down syndrome screening can, to a certain extent, avoid the harm of congenital idiocy of the fetus. The Down syndrome screening method is based on obtaining venous blood from pregnant women, and testing the concentrations of alpha-fetoprotein, human chorionic gonadotropin and free estriol in their blood. Then, combined with B-ultrasound examination and the age and weight of the pregnant woman, etc., the probability of the fetus having the syndrome is determined. Therefore, for pregnant women, after doing the NT examination, they still need to do Down syndrome screening for the health of the fetus. Expectant mothers must not be lazy and do not be lucky.

There are indeed many prenatal check-ups related to pregnancy. Pregnant mothers who are not familiar with them can communicate with the doctor in advance, and then make an order under the doctor's guidance. They will know when to do what examinations, and each examination has its purpose. Expectant mothers should also be clear about it. Don't be confused when doing each examination and don't know what you have checked. Of course, after the examination, you should also consult the doctor carefully about some situations, and learn to read the B-ultrasound order by yourself, so that you can have a clear idea.