NIPT test compared to NHS - HUGE difference in results - opinions?

[user1470147116]

I'm 39 years old and finally pregnant from IVF.

I did the NIPT at 9 weeks (4.5% fatal fraction) test at The Birth Company in London and results were

I didn't have either of them done, but I do have a health background. Yes, it's very normal to get different results on both tests. They test for different things. The combined test tests your hormonal levels (which can be an indicator something is amiss, but not always, so it's not always a very accurate test, but can raise enough of a red flag to find out if you should do further testing) and also baby's development via the nuchal scan. The NIPT test tests for baby's DNA as it's circulating in your blood, so it's much more accurate (also much, much more expensive, which is why it's not offered to everyone as the combined test does a good enough job for most for the cost). So yes, totally normal that they're different and yes, the NIPT is more detailed and accurate so I would feel confident about that result.

The NIPT actually checks the baby’s dna so it’s almost perfectly accurate. The NHS stuff isn’t very accurate and with your age at 39 you were going to be high risk anyway.

I’m getting the NIPT and the midwife suggested not to bother with the nhs bloods. Also, in my area, if you come up high risk on the generic nhs test, the next step is the NIPT ((and not amnio).

What is the breakdown of your combined testing result..?

All it can take is for one outlier result to give you a very high risk

Ordinarily, if you had a high risk combined test, you would be offered a NIPTY test, so that definitely ‘trumps’ the combined test

Obviously you can have an amnio or CVS if you are still worried but the NIPTY is virtually diagnostic for Downs
I think it’s only for Edwards and Patau that it’s less reliable...

My nipt was like yours; I had a consultant appt (due to other issues) and he pointed to my nuchal thickness measurement and said that it was good but my age would put me around 1:50 (I’m 40) anyway. Apparently my age plus blood results (Papp test?) and the NT put me around 1:300 which he was surprised about as he fully expected it to be in double figures based on age alone.

So yes, ignore the nhs one.

As said by another poster Nipt is based on dna so more accurate.

I had the Nipt more for the Edwards and pataus result, I wouldn’t have terminated for Downs.

The consultant also said the Nipt is pretty black and white - ie yes there’s evidence in the dna or no. Not totally 100 so not a screen but usually such wide clear odds that he’d choose to do the Nipt over the nhs one which often has shades of grey.

We had the NIPT that we paid for privately because of our ages and it came back very low risk.

Then we went to our 12w scan and Drs persuaded us it would be a good idea to have combined test anyway. We were a bit unsure but went along with it. Had all the bloods taken, etc.

Then we went into see the midwives and they were like wtf? Why are you having this done if you've already had NIPT? We explained and then we spoke with the lead screening midwife and they all said it was really pointless as the NIPT is so much more reliable than routine NHS screening.
In fact, if we'd had a high risk on the combination, they would've suggested an NIPT as next step, before going to CVS/amniocentesis. (They don't yet offer NIPT on NHS where we are so we'd still have had to pay, or take the NHS amniocentesis option).
So why would you have step 2 (99.2% reliable) then go back and have step 1 (83% reliable), if the advice from a high risk step one result is to have step two to rule more definitively? (I can't recall exact percentages fyi but I think these are pretty close).

Yes it's still a screen but it's as close to a diagnostic test as you'll get without having to have an invasive that carries a risk.
The only way to know 100% is to have a diagnostic and then take the (relatively high) risk of miscarriage.

I had the harmony at 10 weeks and so declined the NHS screening. A friend had a high risk NHS result and then paid for the NIPT. I would trust the NIPT over the NHS testing as it is much more accurate. The NHS testing simply sticks a load of information (including age) into a computer and it chucks out a risk factor. The NIPT looks at the DNA.

I don't really understand from your post why you had the NHS testing having already had a clear NIPT result. We had NIPT done due to age and were told NHS testing after that was completely pointless as so much less accurate.

Mary that was my feeling but the nurse just said to do it anyway. No idea why. Consultant seemed interested in the comparison.

It might have been for the NT actually; I know someone who was clear for all tests but had a thick nt and later baby was found to have a (fixable) heart problem. It may indicate other things? At the same time I know of babies told they had a thick nt and were fine.