Triple test vs. NT scan

[mayerling]

Hi ladies,

I'm here to ask for advice regarding the triple test versus the NT scan.

Yesterday, I had my dating ultrasound/NT scan. Because of the fetal position the tech was unable to perform the NT scan and referred me back to my GP to have the triple test instead. I'm concerned because I don't know whether their rates of accuracy are comparable and the internet doesn't seem to put my fears to rest. Plus, when I asked him whether the results are comparable, he said they are "fairly similar" which only made me feel worse. I basically left the scan feeling more worried than when I went in.

I'm also concerned because I'm booked to have the triple test on Friday at which point I'll be 14w2d. Looking at the chart they gave me with all the dates I'm supposed to have things done, it says that the triple test should be performed from 14w3d to 20w. DH says it's only one day, but I'm thinking if days didn't matter they would have said from 14w to 20w; why say 14w3d if it doesn't really matter? Do you think I should ask them to reschedule the test for after the 14w3d mark?

I'd appreciate any advice on this. Thanks!

 

[mayerling]

Anyone?

 

[stephbolt]

I had both screens offered to me as a "sequential screen." For the second half, they wanted to wait until I was 16w to do the bloodwork, but I'm not sure how much of that is particular to the perinatal practice that was doing the testing and how much is dictated by the test.

I'm a little surprised they told you they just "couldn't do" the NT scan. My baby was very uncooperative as well, but the tech had me roll around for a while and spent some time trying to coax the baby into position to get a measurement and finally did. If you're really concerned, could you push to come back on another day so they could try the NT scan again? But if you are almost 14 weeks, you might be too far for the NT results to be reliable at this point anyway, so perhaps that's their thinking?

Good luck figuring this all out!

 

[amc80]

Check out this page, it has some good information-
http://www.innermostsecrets.com/Left-Menu-Items/Pregnancy/Testing-for-Down-Syndrome/Nuchal-Scans.aspx

 

[mayerling]

Check out this page, it has some good information-
http://www.innermostsecrets.com/Left-Menu-Items/Pregnancy/Testing-for-Down-Syndrome/Nuchal-Scans.aspx

Wow! The triple test misses 1 baby for every 2 that it detects? Those sound like terrible odds.

 

[mayerling]

I had both screens offered to me as a "sequential screen." For the second half, they wanted to wait until I was 16w to do the bloodwork, but I'm not sure how much of that is particular to the perinatal practice that was doing the testing and how much is dictated by the test.

I'm a little surprised they told you they just "couldn't do" the NT scan. My baby was very uncooperative as well, but the tech had me roll around for a while and spent some time trying to coax the baby into position to get a measurement and finally did. If you're really concerned, could you push to come back on another day so they could try the NT scan again? But if you are almost 14 weeks, you might be too far for the NT results to be reliable at this point anyway, so perhaps that's their thinking?

Good luck figuring this all out!

To be fair to them, they did try to coax the baby into cooperating. They had me there for a while, had me jiggle my belly, roll to the left, roll to the right, void my bladder, but that baby refused to assume a horizontal position. And yes, at 14w I suppose getting me in for another NT would be unhelpful. I wish I'd done the scan when I was back home...

 

[ChinaCat]

Is the triple test the blood test? If so, it's my understanding that they are usually done together to get a clearer picture. Neither the NT scan nor the blood test is diagnostic; it cannot tell you anything for sure. It simply tells you your odds or chances based on thickness of the nuchal fold, plus blood work, plus age, plus odds, etc.

I would get the triple test and if it's clear, I wouldn't worry about it. If there is any indication in the bloodwork, then you have an increased risk regardless- an NT scan can't rule anything out.

For example, if someone had a suspiciously thick nuchal fold, then the blood test doesn't matter- your risk is increased regardless. Make sense?

 

[mayerling]

As far as I know, only one is offered in the UK. So if they'd been able to perform the NT, they wouldn't have referred me for the blood test. I don't know, I just feel really worried. I wish I could just request an amniocentesis to put my mind to rest.

 

[megumic]

Are the results a game changer for you?. Like if the gave you a 1/80 chance, which I believe is high since the denominator is usually in the thousands, would you take a different approach? Im just trying to see what you would do with the information, you know? I totally would feel the same anxiety as you, but I also know just personally I wouldn't do anything with the information except educate myself and probably worry. I think if you know how the information will impact you it may help you come to terms with the information you get from the triple test only. But that's just a suggestion, you know? It really depends on your feelings about it.

 

[mayerling]

Yes, the results would be a game changer.

 

[ChinaCat]

Mayerling- Odds are all is fine. But I understand the worry. I don't know how it works in UK- so you can't request an amnio?

ETA: Just b/c they couldn't see anything doesn't mean anything AT ALL. It doesn't make it more or less likely, it simply means it was inconclusive- they just couldn't measure it. So no need for increased worry here!

 

[mayerling]

ChinaCat, you can't request an amnio here. I understand that just because they couldn't measure it, it doesn't mean that the chances are increased; I was just concerned that the triple doesn't offer the accuracy the NT does.

Thanks for everyone's input. DH just sat me down and explained that worrying is needless and what will be will be.

 

[ChinaCat]

Mayerling- Oh I didn't get that you were worried about the accuracy of one versus the other! Sorry!

 

[megumic]

I agree with your DH. Don't worry lady. There is enough insane amounts of worry that come with pregnancy that you dont need to worry on this too. On another board one girl said, the more you worry the more you're missing out on this amazing miraculous experience. I think she is right and I know I am the first one to worry, but it is true that this is a huge miracle and we should all embrace it while we can!

 

[Laila619]

I'm also concerned because I'm booked to have the triple test on Friday at which point I'll be 14w2d. Looking at the chart they gave me with all the dates I'm supposed to have things done, it says that the triple test should be performed from 14w3d to 20w. DH says it's only one day, but I'm thinking if days didn't matter they would have said from 14w to 20w; why say 14w3d if it doesn't really matter? Do you think I should ask them to reschedule the test for after the 14w3d mark?

Yes. It's supposed to be done during a certain time frame, and they need to follow that. The reason why is because of the hormone levels in the blood stream. Too early or too late will throw off the results.

 

[mayerling]

Okay, I've rescheduled for 14w6d.

 

[Pandora II]

Mayerling, did you ask them to request an amnio for you? They don't say yes in all cases but it might be possible since your NT scan wasn't possible. Did they manage to check soft markers like nasal bone at the scan?

Privately they cost around £450.

Good luck with the TT.

 

[Puppmom]

Mayerling, if I remember correctly, the NT scan has to be done between 11 and 13 weeks so maybe that's why they didn't offer a follow up ultrasound?

 

[mayerling]

Mayerling, if I remember correctly, the NT scan has to be done between 11 and 13 weeks so maybe that's why they didn't offer a follow up ultrasound?

Yes, this is why they didn't offer another ultrasound.

 

[mayerling]

Mayerling, did you ask them to request an amnio for you? They don't say yes in all cases but it might be possible since your NT scan wasn't possible. Did they manage to check soft markers like nasal bone at the scan?

Privately they cost around £450.

Good luck with the TT.

No, I didn't. Should I ask the GP? If they checked the nasal bone, they didn't tell me about it. My obstetrician back home said he could see the nasal bone at 10w3d, but I don't know whether being able to see it is enough or whether they run measurements on it.

 

[Pandora II]

Mayerling, did you ask them to request an amnio for you? They don't say yes in all cases but it might be possible since your NT scan wasn't possible. Did they manage to check soft markers like nasal bone at the scan?

Privately they cost around £450.

Good luck with the TT.

No, I didn't. Should I ask the GP? If they checked the nasal bone, they didn't tell me about it. My obstetrician back home said he could see the nasal bone at 10w3d, but I don't know whether being able to see it is enough or whether they run measurements on it.

They don't run measurements on it, but there are a number of what they call 'soft markers' for Trisomy disorders and the lack of a nasal bone is a very important one. The fact that your OB could see one at 10w 3d if great - and it will be one of the reasons that he mentioned being able to see it.

If you are really, really worried then I would ask the GP to refer you. A lot will depend on the relationship you have with your GP and also what you would do if the result was positive - if you would terminate then they are much more likely to offer you the test. If it was just for information then they likely wouldnt advise the risk.

I discussed the scenario with my GP - I was over 35 and for a number of reasons DH and I would have terminated the pregnancy for chromosmal abnormalities. He said that he would refer me if I wasn't happy with the numbers - my cut off was a bit higher than the hospitals. In the event my numbers were great so I didn't need to go further

 

[mayerling]

Mayerling, did you ask them to request an amnio for you? They don't say yes in all cases but it might be possible since your NT scan wasn't possible. Did they manage to check soft markers like nasal bone at the scan?

Privately they cost around £450.

Good luck with the TT.

No, I didn't. Should I ask the GP? If they checked the nasal bone, they didn't tell me about it. My obstetrician back home said he could see the nasal bone at 10w3d, but I don't know whether being able to see it is enough or whether they run measurements on it.

They don't run measurements on it, but there are a number of what they call 'soft markers' for Trisomy disorders and the lack of a nasal bone is a very important one. The fact that your OB could see one at 10w 3d if great - and it will be one of the reasons that he mentioned being able to see it.

If you are really, really worried then I would ask the GP to refer you. A lot will depend on the relationship you have with your GP and also what you would do if the result was positive - if you would terminate then they are much more likely to offer you the test. If it was just for information then they likely wouldnt advise the risk.

I discussed the scenario with my GP - I was over 35 and for a number of reasons DH and I would have terminated the pregnancy for chromosmal abnormalities. He said that he would refer me if I wasn't happy with the numbers - my cut off was a bit higher than the hospitals. In the event my numbers were great so I didn't need to go further

Yes, DH and I have decided, for reasons I won't get into right now, that we will terminate if we're not happy with the numbers. I don't really have a GP. I go to the surgery and see whoever's available. I suppose I should just make an appointment once the results come in, and discuss it with whoever sees me on the day.

Once again, Pandora, you are my source of information . I am happy with the fact that my OB was able to see the nasal bone so early in the baby's development. In fact, DH and I joked that the baby takes after its mummy (I have a huge nose )!

 

[mayerling]

I just received the triple test results. Thankfully the baby has a low risk for down syndrome (1 in 3500). I don't understand stats very much, but DH does and he insists that it's an excellent result so we're breathing a sigh of relief. They also said that my AFP was not elevated indicated very low risk for spina bifida.

 

[Skippy123]

I just received the triple test results. Thankfully the baby has a low risk for down syndrome (1 in 3500). I don't understand stats very much, but DH does and he insists that it's an excellent result so we're breathing a sigh of relief. They also said that my AFP was not elevated indicated very low risk for spina bifida.

oh good. I am glad you feel better!