Down screening test

[renniem]

Do you know how accurate this test is in identifying Down syndrome? I was told today that I have high chances, 1/216 specifically of having a baby with Down.

However I am extremely confused as I was under the impression that the NHS performed the NIPT test along with the 13 week scan which doesn't actually seem to be the case.

I am also overweight with a BMI of 36 and 38 years old so I wonder how that may have impacted the outcome.

I am reluctant of having an amniocentesis as I have had a very bad experience with the NHS so far both in this as well as in my previous pregnancy and plan to ask for the actual NIPT test, but in the meantime I'm interested in hearing from anyone who was high risk and what the final outcome was. Do you suggest the NIPT test or do you think amniocentesis is more accurate?

I should mention that after the phone call from the midwife today I was left with the impression that only amniocentesis is accurate but after researching this further not only does it not seem to be the case but also it's better to do the NIPT initially regardless and only proceed with amniocentesis depending on the outcome.

At this point I just want to know, and despite of the outcome I have no intention of termination.

I don’t know the answer to that exactly, but I just wanted to share my experience. DD had a Down’s ratio of 1:10 at the nuchal test at 13 weeks, and I had an amnio at 16 weeks. It was a very fraught 3 weeks, but it turned out that she was perfectly ok. I was told at the amnio that the results would take a week, but actually they called me on the third day to say that it was all fine. The procedure itself was nerve-wracking but not painful - you watch the needle going in on the ultrasound, and it looks like it’s getting really close to the baby, but they knew what they were doing and it didn’t touch her.

I know it’s scary - take your time and think about your options. Did they offer to let you talk to the Fetal Medicine team directly?

Most trusts don't offer the NIPT unless your high risk. I think even then they go to CVS/amnio instead of high risk identified. My area is 1/150. I had to go private due to this reason. From what I gather the amnio is more accurate as this gives you a yes or no answer. Where as the NIPT is still probability. Which should be more accurate than the standard test initially carried out.

Someone may come along and correct me..

Your age will likely be a factor. It is taken into account with the combined screening test, alongside your NT measurement, HCG and Papp-A results.

I recommend looking at www.arc-uk.org/ for further information on the tests available to you. The NIPT isn't diagnostic, but it is a better screening test that the combined test.

It is also worth remembering that a 1 in 216 outcome is about a 0.5% chance of there being something wrong. Try to focus on this.

I have been through the testing, so know how you are feeling. I am sorry this is happening to you.

I chose not to have a test with both of my pregancies due to my beliefs.
However,I also seen many false positive and false negative results when working in medical field (positive result-baby fine/negative - baby with Trisomy 21). The only test that will confirm trisomies is ether CVS or amniocentesis.

I'm 37 (and was at time of NT also). I had a 1 in 212 for T21, which isn't considered high risk at my local trust. Baby had NT of 2.8, papp-a 1.51 MoM and bhcg 1.9 MoM. She's fine, 2 days old now. The age part of the calculation is quite brutal!

I am 38 and was told from the start that my combined risk score would be high based on my age alone.

On that basis I declined the nhs combined screening tests and instead opted to pay privately for a SAFE nipt (which is the best nipt for women with a higher bmi).

I then got my results within a week that came back as 1:100,000.

They did the calculation for me based on just my age, and nothing else and this came back as 1:159 for t21. So had I gone for the combined screening I’d have received a high risk.

I’ve since had my 20 week scan and everything still looks perfect.

The nipt is there to offer a far more accurate probability but is not diagnostic. Many women will opt for a nipt and then go onto have the more invasive testing dependant upon the results of the nipt.

Good luck. As a pp said your result is actually still super low risk.

I was 37 almost 38 when I had the combined test and came out as high risk for one of my twins- I think it was a similar ratio to yours. I ended up having the CVS, within a couple of days- it wasn't a particularly nice procedure and I had to be "kebabed" as the consultant put it as they needed to test both babies but results came back negative. CVS and amino are the only diagnostic tests

Age plays a significant part, I am 45 and mine came back as 1:256 which was low for my age group. When I had my second child at 32 my results came back as very high 1:300, I refused to have an amnio - they must have offered me a NIPt then but I didn't know it was a NIPT where I had a blood test done and the results came back as 1:100000. It's so worrisome isn't it.

It's not really that high risk - chances are very good (215/216) of a healthy baby. So don't panic!

CVS or amnio will tell you for sure but the NIPT test is fairly accurate and more appropriate for you given that it's non invasive, your risk level isn't that high and you wouldn't terminate.

www.downs-syndrome.org.uk/?wpdmdl=29920

The above link explains the NIPT.
Your risk is higher due to your age, and that’s because the older you are, the greater the chance of having a baby with a genetic condition.

You usually need to pay privately for the NIPT test, it’s around £4-500 but some trusts offer it cheaper with them.

@TooExtraImmatureCheddar no I was not offered to speak to the Fetal medicine team.

After looking more into this I decided to have the NIPT test done. This is a natural pregnancy after an IVF (I have a one year old) and 11 years of trying for a baby so for me a procedure with 1% chance of aborting at this stage is not an option.

When I booked the appointment i also asked to know more about my results:
free β-hCG 1.43MoM
Papp-A 0.33MoM
NT 1.8mm

What is confusing is that the Nuchal Translucency is on the low side and hCG is not that high. Down's is usually indicated by high hCG (above 2), low Papp-A and high NT (please correct me if I'm wrong).

Given the additional risk factors I understand how the calculation would put me in a relatively high risk category but also due to my low Papp-A I would have expected a consultant appointment and to be both informed and offered some treatment options as a result under 0.4 potentially means low oxygenation of the placenta and a small or premature baby. Does anyone have any experience with that? I found a paper from an NHS trust specific to Papp-A levels and also discussed this with a doctor friend - who is not a gynaecologist but has studied fetal medicine.

Regarding the accuracy of the NIPT test I have been told that second generation NIPT have a very high accuracy (over 99%) so at least outside the UK amnio is not the only option when it comes to a diagnosis. The veracity test in particular is the one I have been recommended.

I don't know what type of NIPT Scotland offers but for now I'm just going to do that and after I speak with a consultant (I hope to manage to book an appointment when I go to get my bloods on Monday) I'll see if I feel the need for further testing.

Hi OP,

In my trust you would only have been considered high risk with a result of 1:150 or above. Some trusts do offer the NIPT and for trisomy 21 it’s about 99% accurate in giving you a risk factor which will look something like >1:10,000. T13/18 are slightly less accurate on a NIPT but still around 96-98%. Amniocentesis or CVS is the only way to get an official diagnosis as although NIPT is highly accurate it is not considered a diagnostic test. Women that have a high risk NIPT are then offered an amnio to confirm diagnosis if they wish to terminate the pregnancy. I think a low risk NIPT should be considered very reassuring in your case, the low PAPP-A and your age will probably have increased your risk, although high NT can be associated with chromononsal conditions, 50% of babies with Down syndrome will not show a single feature of T21 on ultrasound. Just be aware that sometimes with a raised BMI your NIPT can come back as inconclusive but the chance of this lessens as your gestation increases🙂

Hello, I’m 40 and almost 14 weeks. I was told on Thursday that my combined screening result for 1 in 71 for Downs Syndrome. I was very shocked and upset on hearing this but after doing further research I’ve gleaned that my age is a big factor in the numbers as the fluid measurement was normal. I paid for a private Harmony blood test yesterday (£495 so not cheap) but as others have said it’s 99% accurate and tests the baby’s dna which is now in my blood. I refused the amnio as I’ve had four miscarriages before this pregnancy and whilst the risk is relatively low and has been overstated over the years, it’s not one I’m personally willing to take. As I understand it the NHS only offers CVS or amnio and not any other NIPT. Good luck! I hope that helps a little

I had a low chance come back at my combined screening and no one discussed the results, I didn’t realise on the back in small print that it gives the chance! I just read the front of the letter which said low chance and thought nothing of it. All my scans were fine, even one at 38 weeks. When my son was born, we found out he had Down syndrome at 5 days old! Obviously this was a big shock and I was annoyed my midwife didn’t go through my results as I’ve since learnt it was 1:210! I would still have gone ahead with the pregnancy if I had known but it would have been nice to have been prepared! There’s also a lot of support out there which some hospitals aren’t great at signposting parents too! My son is absolutely gorgeous and is doing really well! Just for future reference, we say high chance now and not high risk as we don’t see our babies as a risk but this is something I’ve learnt since having my son so just spreading the word :-) really hope everything works out for you x

Hi,
I have had my results come back from my 12 weeks scan and I was classed as low risk at 1:211 and I’m 35 with low Papp-a

[quote renniem]@TooExtraImmatureCheddar no I was not offered to speak to the Fetal medicine team.

After looking more into this I decided to have the NIPT test done. This is a natural pregnancy after an IVF (I have a one year old) and 11 years of trying for a baby so for me a procedure with 1% chance of aborting at this stage is not an option.

When I booked the appointment i also asked to know more about my results:
free β-hCG 1.43MoM
Papp-A 0.33MoM
NT 1.8mm

What is confusing is that the Nuchal Translucency is on the low side and hCG is not that high. Down's is usually indicated by high hCG (above 2), low Papp-A and high NT (please correct me if I'm wrong).

Given the additional risk factors I understand how the calculation would put me in a relatively high risk category but also due to my low Papp-A I would have expected a consultant appointment and to be both informed and offered some treatment options as a result under 0.4 potentially means low oxygenation of the placenta and a small or premature baby. Does anyone have any experience with that? I found a paper from an NHS trust specific to Papp-A levels and also discussed this with a doctor friend - who is not a gynaecologist but has studied fetal medicine.

Regarding the accuracy of the NIPT test I have been told that second generation NIPT have a very high accuracy (over 99%) so at least outside the UK amnio is not the only option when it comes to a diagnosis. The veracity test in particular is the one I have been recommended.

I don't know what type of NIPT Scotland offers but for now I'm just going to do that and after I speak with a consultant (I hope to manage to book an appointment when I go to get my bloods on Monday) I'll see if I feel the need for further testing.

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Hi! I hope you are well. I just wondered how you got on with further tests/scan? My results are similar to yours. I'm having my 20 week anomaly scan on Friday but have spent the past 8 weeks reflecting on my results. I am only 28 at term. My bmi was creeping into the 'overweight' however they did use my weight at 12 weeks where I was incredibly bloated and full of water. I weigh roughly 9 stone 2 upon conception.

My results at 11.5 were Papp-a 0.34mom
Hcg 1.25mom
Nt was 1.6mm equalling 1.22mom

My age related risk was 1 in 1152 but my risk at term is 1 in 362.

I understand this is still low risk however I can't understand how I'm 3 x more likely than someone else my age? My results apart from Papp-a are so close to 1. Fetal medicine nor midwives have offered much by the way of advice or explanation.

I was booked for a harmony 10 days ago but the labs machines broke. So decided to wait till nhs anomaly. But still worrying, have booked panorama for next Tuesday.

I just wondered how you'd got on? Xx