Normal to have a Nuchal Translucency Test?

[Anonymous]

14:01 poster here, and actually both of my NTs included anatomy scans. Obviously, many things aren't evident at this point, but they can count limbs, try to visualize the heart, measure the stomach and head, etc. So in fact it is a "general indication of fetal health," as well as a specific risk assessment for three chromosomal disorders.

And the 20 week U/S also provides the opportunity for "false positives" since some abormalities identified at that point -- including a kidney issue seen on both of my sons' 20-week U/Ss -- can resolve before birth or simply disappear on a subsequent U/S. In fact, the idea of "false positives" is silly in the context of a risk assessment -- there are no positives or negatives, only odds.

Again, it's a patient's choice whether or not to undergo any test. But I think that attempting to separate the NT out as something you get only if you care about chromosomal abnormalities is a narrow way of viewing the test.

[Anonymous]

PP here who has friends who have had children born with genetic (heart) defects. Some of the my friends did have the NT and the ultrasound showed no problems at that point. Yet the 20 week ultrasound picked up on very serious life-threatening heart defects. Yes, there may be some genetic abnormalities that the NT ultrasound happens to pick up, but it is still very early in the pregnancy and the screen itself is designed only to test for Trisomy 21, 18, and 13. I'm sure as time progresses, that the NT will improve and cover more conditions. I just don't want people to get the impression that the ultrasound done between 11 and 13 weeks gives the same depth of information that one at 20 weeks currently does. That being said, both can give indications of potential problems (aka: soft markers) when in fact there is no problem or the problem resolves on its own before birth.

[Anonymous]

Right, as I said in an earlier post, the NT is not a replacement for the 20 week US. My point was that they are both aimed at assessing fetal health. Ultimately, I sense that people opposed to the NT think that its primary purpose is identifying chromosomal problems so that people can terminate. In fact, it's a screening that gives you information about the health and development of your baby, just as the 20 week scan does.

[Anonymous]

I think that the point that posters who choose to forego the NT are trying to make is that some people are more prone to worrying than others. And since the NT does not provide any hard facts - just estimates, possibilities and potential false positives, the test would only cause unnecessary worrying. Because I am this way myself, and because I'm 40 and age alone would have given me worse NT results, I did not want the NT. However, I went straight for CVS which gave me definitive results. But I understand that many people would not want to take that risk.

[Anonymous]

I was told that the NT mostly measures the "fat rolls" on the back of the fetus's neck, which have nothing to do with, but are an indicator of Downs and other issues. Kinda cool that they picked that up. Anything else they are looking at is kinda extra, but NOT the indicator. I have had two NT and I had them replace the triple screen due to the results.

[Anonymous]

FYI, the use of the phrase "false positives" isn't really accurate here. The NT is not diagnostic - so it can't give you positive or negative anything. The genetic counselors who provide your results are very clear that what you're dealing with are odds, not definitive diagnoses. So you can't get a false positive or false negative from an NT, although conceivably you can get a false sense of assurance or false reason for concern. But that exists irrespective of this text - for those of us who are on the older side of the spectrum, we're already aware of escalating odds for Downs and other issues. I think it's unfortunate for people to skip the NT out of concern it will mislead them or worry them unnecessarily - unfortunately, lots of us have too many reasons to worry at the outset, and the NT is a risk-free way of potentially alleviating (not ending) some of those worries.

[Anonymous]

I think it depends on where you have the test, and when you had it. In addition, to measuring the thickness of the neck, the doctor examined the baby's heart and looked to make sure the baby had a nose bone.

[Anonymous]

Anonymous wrote:FYI, the use of the phrase "false positives" isn't really accurate here. The NT is not diagnostic - so it can't give you positive or negative anything. The genetic counselors who provide your results are very clear that what you're dealing with are odds, not definitive diagnoses. So you can't get a false positive or false negative from an NT, although conceivably you can get a false sense of assurance or false reason for concern. But that exists irrespective of this text - for those of us who are on the older side of the spectrum, we're already aware of escalating odds for Downs and other issues. I think it's unfortunate for people to skip the NT out of concern it will mislead them or worry them unnecessarily - unfortunately, lots of us have too many reasons to worry at the outset, and the NT is a risk-free way of potentially alleviating (not ending) some of those worries.

I agree with you here. What is really interesting is that people get nervous about the NT, but the triple screen truly has quite a false positive rate, leading people to have invasive procedures that can put the fetus at harm!

[Anonymous]

Heart defects and lack of a nose bone can also signs of Down Syndrome. That is why the look at them as part of the NT.

[Anonymous]

I disagree about the NT and false positives. I didn't have the NT but they found cysts on my baby's brain during my 20-week ultrasound. These cysts are a marker for Downs Syndrome. They would have told me that there's a possibility that my baby had Downs Syndrome had I not had CVS showing that all the chromosomes are okay. I imagine that the NT could give somebody a similar scare.

[Anonymous]

The high risk specialist that I saw for the test recently said that 80-85% of the Trisomy 13, 18, and 21 cases will be picked up with this u/s. The quad screen a few weeks later will pick up another 5-10%, so with the combo of both tests, you greatly reduce your odds of not detecting these genetic abmormalities until birth.

I was on the fence about having the NT, but am a Type A "planner". I thought if I found out my chances were high, I would probably go for the diagnotic testing. If the baby had Downs we could become educated ahead of time and be more prepared. Once I read about Trisomy 18 (? could be wrong on the chromosome) effects, it sealed the deal for me. I am not necessaily again abortion in several circumstances, but I didn't think I could ever go through with one until I read about this defect. I believe the information I received said 90% of the babies are stillborn and the remainder don't live past a day or two. I don't think I could go through that and then start all over trying to have another baby months later. I have a close friend who lost a baby at 6months pg and then delivered her 2nd prematurely at 1lb 8oz. The struggle almost killed their marraige and I really think almost killed her. Why make a baby suffer for those few days if it survives the birth? That was my personal reason for doing the test. But I undestand it is a very personal decision.

[Anonymous]

I looked at it as another ultra sound because basically that is what it is at 11 weeks. Better than an amino, which I would not do. good luck with your choice.

[kabol77]

My son is 21 months and I wasn't offered the test with him. I'm now 24 wks pregnant and under 35. My Dr suggested I take the test but I decided not too. It seems like a waste of time and you don't need the undue stress of waiting for most likely negative results, which can take a few weeks to get. I opted for the blood test that can determine the same things at 16 weeks. Result: I was negative of course.

Ask your Dr about the 16 week blood test instead, & good luck!

[Anonymous]

The AFP/quad screen (which is what I assume you mean by the "16-week blood test) is actually less reliable than the NT screen AND has a higher incidence of false positives. Also, the NT does not take all that long - I think I may have had the results in 2 weeks.