01.Do I need to have a mid-term pregnancy test after having an early-term pregnancy test?
No, unless it is a combined screening test for early and midterm pregnancy, so under normal circumstances, you do not need to do the midterm test after having the early test. However, since the serological indexes of the early pregnancy test do not include AFP, if you want to use the serological test to screen for neural tube defects, you also need to have a blood test for AFP during the middle pregnancy. If the AFP is not checked, the possibility of neural tube defects needs to be carefully ruled out during the mid-trimester ultrasound screening for large malformations.
02.I am not sure about the high risk of Down’s syndrome screening, but I don’t want to do amniocentesis, can I repeat it?
Repeat screening is not recommended. First of all, screening itself is a risk estimation, not a diagnosis, so it is not clinically meaningful to repeat it. Secondly, if the repeat comes out to be a high risk, it is a waste of time. If the repeat comes out to be a low risk, will you choose to believe the high risk result or the low risk result? Or is it an endless tangle. Third, in most cases the results of repeat screening are consistent with the results of the first screening.
For patients with a high risk of Down’s syndrome, there are currently two options: one is to do “advanced screening”, that is, non-invasive fetal DNA testing (NIPT), if the risk value is not too high (less than 1/50 risk of Down’s syndrome), and the other option is to do amniocentesis directly.
03. Since the detection rate of Down’s syndrome screening is not that high, why do we need to do it?
The detection rate for mid-Tang is about 70% and for early-Tang is about 85%. These figures seem unsatisfactory, so why do it?
The main reason is that the Down screening test is simple and cost-effective, and the number of people covered can be relatively large. For the less satisfactory detection rate we can think the other way around, if we don’t do Down’s screening, 100% of all Down’s syndrome will be missed, if we do it, we can detect an additional 70% of Down’s syndrome in the middle and 85% of Down’s syndrome in the early.
As a screening program, Down’s syndrome screening in early and mid pregnancy is still affordable.
04. Non-invasive fetal DNA testing (NIPT) can detect Down’s syndrome at a rate of 99%, so why not simply use NIPT instead of serological Down’s screening?
The main reason is that the NIPT test is complex, takes a long time, and requires expensive equipment, which is also more expensive, about 10 times more expensive than the Down’s syndrome test. Therefore, both technically and in terms of cost, it cannot be widely promoted. As technology advances, the price and cost of testing equipment will drop significantly, and when it reaches an equilibrium point, it is possible to consider replacing serological “Down screening” with “non-invasive” testing.
However, at present, the non-invasive test can only be used as an “advanced screening test” and cannot replace the serological “Down screening”. If you are financially well off, you can choose non-invasive screening as the first-line screening option.
05. I have already had the early screening, why do I need to have the screening at 24-28 weeks of pregnancy?
Auntie, you are mistaken, what you need to do from 24 to 28 weeks is glucose screening for gestational diabetes. The “sugar baby” is also not the “Tang baby”.
06.What should I do if I have a soft ultrasound marker during the subsequent ultrasound test after a low risk screening?
One is to recalculate the risk of Down’s syndrome by combining the results of the serological screening with the risk values of the different ultrasound soft markers, and then decide whether amniocentesis is needed based on the adjusted risk values. The other option is to do a direct “non-invasive” screening and then determine the need for amniocentesis based on the results of the test.
There is no international consensus as to which option is more appropriate, so you can choose according to the technical conditions of the hospital, your financial situation and your personal wishes.
07.Is amniocentesis painful? Why is there no anesthesia during amniocentesis?
Anyone who has had an amniocentesis knows that it is not as painful as you think, basically it is similar to the pain of a shot in the buttocks.
Why is there no anesthesia during amniocentesis? After the anesthesia, you have to use the puncture needle again. Besides, you see who in the buttocks before the injection will be a shot of anesthesia?