NIPT before combined NHS test?

[Colinthecaterpillar35]

Hi all

We want to be as informed as we can about our baby's health and would like, within reason, to have as many test done as possible.

I've been told by my midwife that my dating scan will be between 12-13 weeks and that the combined test will be done then. Am I able to have an NIPT test privately before my dating scan or can this only be done afterwards? We just really want to be aware of our circumstances as early as possible as I'm concerned my age (35) will play a big factor in the risks.

Any advice/experience greatly received.

Here is the info about SAFE's PPV:

www.thebirthcompany.co.uk/safe-test.php

Panorama also checks against a wider range of conditions for those who are reading this thread and wondering what to compare when looking at NIPT tests.

And here is a link to a good leaflet (IMO) from Harmony explaining what factors are taken into account in producing NIPT results, how PPV is measured and why PPV values vary depending on various factors. This explains why PPV figures aren't the most useful to look at when deciding on NIPT:

www.harmonytest.com/global/en/nipt-positive-predictive-value-ppv.html

@PurplePansy05 the 99% accuracy for NPV for the SAFE test which our hospital does is what we found reassuring, plus our hospital offers it for £350. We were really happy with it xx

We had NIPT before the NHS scan as if it was bad news I’d want to know as early as possible especially if we decided to terminate (we’d have had CVS or amnio as diagnostic test if needed).

I had Harmony at 10+3 and NHS scan a fortnight later, they didn’t do the combined test as the Harmony was more accurate.
I’d always suggest NIPT early, as long as you are confident with dates.

I believe harmony had lower accuracy for edwards and pataus - but I looked at so many articles at the time I honestly can’t remember where I saw that now xx

@Colinthecaterpillar35- I paid for the NIPT at 10+5 weeks due to it being my 1st pregnancy age 38. Unfortunately, it came back as showing patau syndrome. The clinic called me back in and did a more detailed scan and checked the NT- 6.5mm! The scan also showed obvious abnormalities (huge hernia, cleft face, brain issues among other things). We were offered CVS or waiting another 5 weeks to an amnio. After discussion, and the fact that anomolies were so obvious on the scan, we had a TFMR at 11 weeks.

For me, I was SO glad to have options so early on. The TFMR was much easier both physically and psychologically at 11 weeks than later on. I wasn't showing as yet and no one knew. I know of cases where they don't get the 12 week scan till 14 weeks or even later!

I have read that 'some' NHS trusts offer NIPT, but only if your 12 weeks scan bloods come back at 1:150 chance of more. Again, you might not even get these bloods back till 14 weeks, then the NIPT weeks later! Too late IMO. Patau is rare though. This was just my experience so you hear another side.

If you do decide to have the NIPT- check what is included. Some private places offer a scan later on in addition to the one during the NIPT and others offer different packages. Check where the blood test will be analysed. Some places still sent the samples to the USA, which can add a week or more onto getting results back. Ask how you will be notified of your results and next steps. I've heard of cases of people being texted bad news and told to follow up themselves at a hospital or BPAS!!! Unacceptable.

If you have any questions, feel free to ask.x

Sorry, despite my massive reply, I realise I didnt even answer your questions OP. Yes, NIPT can be done from 10 weeks in most cases, some even at 9 weeks. Its about how much DNA from the foetus is circulating in your blood. There are cases where its too early and they need to repeat. Also, if you have a high BMI, they might need to repeat. If you go ahead, do check if you need to pay if they need to bring you back for a repeat blood test.

@Elouera first off, wanted to say really sorry for your loss. I also hope you don’t object to me offering a differing perspective following quite a bit of experience in this area, including my own.

The dating scan should happen from 10 weeks, and should be done by 14 weeks at the latest on the NHS. At this point, bloods can be taken to assess risk for trisomy as well as placental function. As such, you can have a screening test (albeit less sensitive than NIPT) and a scan, within the timeframes you describe.

Generally NIPT is less than 50% accurate at predicting Edwards or Patau’s. In Edwards, near enough 2/3 of positive detections are false positives with NIPT. This can cause a great deal of alarm as clinicians tell you such conditions are “incompatible with life”.

From my own experience, it was explained to me that such conditions are often not identifiable in early ultrasound, or sometimes until final trimester. The anomaly scan at 20 weeks is timed as such that most life threatening complications can be detected then. If conditions are so severe that they can be detected in the first trimester, often the actual condition causing complications is not as significant as the fact abnormalities at this stage are likely to indicate serious issues and a worse prognosis - as such a positive NIPT may add little clinical weight in terms of decision to terminate for some people (although not all). In such an instance NHS screening and an option for rapid CVS might also inform decision making - I am not sure NIPT would necessarily add much. But it is a personal decision.

I just wanted to put this forward as many think screening tests and diagnostic tests are quick processes but it can be very complex and drawn out. I imagine being told baby had positive NIPT at 9-10 weeks pregnant - with normal ultrasound would be deeply traumatic. I know many people who have experienced this who have been left traumatised.

I went through an array of screening and diagnostic tests for Edwards Syndrome and was told prognosis was poor. 6 months of my pregnancy was marred by this. My baby was born perfectly healthy. These tests really aren’t conclusive for everyone...

@SarahD19- Yes, there are certainly 2 sides to a coin and NIPT is certainly not a conclusive diagnosis. In our case the autopsy did confirm the diagnosis of T13, although I'm aware that NIPT isnt 100%- esp for T13/T18. I'm glad your pregnancy worked out and all was well.

I think the issue isn't with the tests but with the fact many people don't understand what it actually does, that it isn't diagnostic, and they don't understand the results.

For me, after 3 MCs and in my mid-30s, like many posters on this thread, I would have much rather known that there is a potential issue asap so any tests that may indicate such risk is welcome. And of course you then move on to diagnostic tests if necessary, that's where it makes sense IMO.

@PurplePansy05 completely agree that misinformation is rampant across professionals and those taking the tests. It is very good for a screening test, but bottom line, NIPT is only a screening.

I sense sometimes people seek out these tests for a sense of reassurance that cannot be provided - and the manufacturers of these tests tap into this and try to promise assurance that is not possible. For instance the majority of conditions cannot be risk assessed through NIPT. Yet people will take the test and say “oh it’s worth paying the money as now I know my baby will definitely be healthy”. The majority of prenatal conditions and loss, we have little or zero understanding of. The anomaly scan at around 20 weeks is also timed as such, as this is when most structural and serious defects can be detected - and not consistently before. Also, statistically speaking, placental health may be the biggest risk factor in terms of infant and maternal loss during pregnancy. Many do not appreciate much of the NHS tests monitor and test for these conditions, whilst NIPT is restricted to the 3 Trisomies (and where it is not, the accuracy is dubious and has been flagged as unreliable).

With prenatal tests in general, I’ve also found my expectations of what I’d want versus the realities are very different. I’ve experienced MCs myself and always thought if there was anything wrong, I’d “want to know everything”. However I’ve come to realise all prenatal tests are profoundly limited and cannot always give the answers you would seek. To me, that sense of incomplete information/science being presented as cutting edge and factual, fully informative etc is possibly worse than not having any information or explanation. My views have changed drastically through that lived experience. However I appreciate these are strictly my views and am not making generalised statements.

Don’t get me wrong, all these tests have their place imho - but I do find many people have an unrealistic expectation of what information can be gauged from these tests. I wish more accurate information was widespread and easily accessible. The NIPT is a fantastic tool, but we do need a shared understanding of it’s limitations.

@Elouera thank you. I wish you every happiness in the future.

Thank you to everyone who has shared information and experiences on this thread, I really appreciate it - it gives me a lot to consider 👍

@Colinthecaterpillar35 good luck with everything! Whatever you decide moving forward, I hope is whatever feels right for you. Thinking of you x