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False Negatives NIPT

(9 Posts)
Tqlina Fri 28-Aug-20 20:52:44

Hi all, I had a false negative with Natera Panorama's test. I was given a 'low risk' result (something like less than 1 in 10,000). It has been a complicated process for me to come to terms with. The tests are portrayed as being so accurate. I am just wondering whether anyone else has experienced this. I think they are far more common than the companies let on. We are the parents of an amazing and beautiful child with down syndrome. I am grateful everyday she is with us and she truly is my heart. But I also feel angry with how these companies are portraying their products and I am increasingly concerned as they reach out to larger markets (not just older or supposedly high risk women). I would be very interested to hear of other people that have struggled to come to terms with false negative and false positive results.

OP’s posts: |
NG86 Sat 29-Aug-20 07:32:49

Hi,

Congratulations on the birth of your little one.

I haven't had a false negative, but I have had the experience of a positive NIPT followed by a negative amniocentesis for T18. I can honestly say that despite the good news from the amniocentesis, the NIPT result has put a huge dark cloud over my pregnancy and I have had to seek counselling for my anxiety. It has taken the enjoyment out of my pregnancy, and I wish I had gone straight for the amnio (but nhs restrictions with a low risk combined NT screen didn't allow). I think a lot of my anxiety has come from the promotion of the accuracy of the NIPT, and although I have a science background and understand that it's screening and not diagnostic, it has been hard to let go and enjoy pregnancy.

All the best and enjoy your wonderful daughter. thanks

Tqlina Sat 29-Aug-20 13:12:10

Thank you for sharing this. I completely understand about the anxiety it may have caused. I was also given a relatively low risk based on my scans but given my age (over 35) the NIPT was recommended. I have subsequently learned that if one is overweight the tests might be less accurate, but my weight is normal. So it is hard to understand what happened (I actually had the test twice). It has also caused me alot of anxiety.
I think there have been far more false positives, simply because down syndrome, and other trisomies are pretty rare. So the likelihood of having a false negative is less than a false positive. I have found this ASA ruling to be particularly important about how the accuracy of these tests is portrayed: www.asa.org.uk/news/non-invasive-prenatal-testing-nipt-a-look-at-the-asa-s-rulings.html but the companies are still engaging in direct consumer marketing and they are guilty of misleading consumers. I have also since learned that the tests are not even approved by the US Food and Drug Administration (FDA). With the big companies largely based in California, it is difficult to see how the will be held to account.

OP’s posts: |
Aria2015 Sat 29-Aug-20 13:44:00

@Tqlina congratulations on the birth of your baby. It must have been quite a shock though given your NIPT result.

I had the NIPT (Harmony) after getting a high risk combined screening (1:110). The baby's NT was 2.2mm, well within the normal range so the high risk result was due to age (38) and also a slightly higher hcg level.

My results for the Harmony NIPT came back low risk (1:10,000). I haven't had my baby yet but I have to say that it has crossed my mind as a worry that the NIPT could be wrong. I've googled it quite a bit and false negatives do seem to be very rare with far more people having false positives.

I think the hard thing is that all the consultants and midwives etc... That I've seen, have had the attitude that the NIPT is as good as 100% so when I've mentioned been worried that it might not be, they've just dismissed it as me being over anxious.

Can I ask, did you have any additional scans to the 12 weeks and 20 week scans? Also, you mention you took the NIPT test twice. Did you get low risk both times?

NG86 Sat 29-Aug-20 15:31:44

Tqlina

Thank you for sharing this. I completely understand about the anxiety it may have caused. I was also given a relatively low risk based on my scans but given my age (over 35) the NIPT was recommended. I have subsequently learned that if one is overweight the tests might be less accurate, but my weight is normal. So it is hard to understand what happened (I actually had the test twice). It has also caused me alot of anxiety.
I think there have been far more false positives, simply because down syndrome, and other trisomies are pretty rare. So the likelihood of having a false negative is less than a false positive. I have found this ASA ruling to be particularly important about how the accuracy of these tests is portrayed: https://www.asa.org.uk/news/non-invasive-prenatal-testing-nipt-a-look-at-the-asa-s-rulings.html but the companies are still engaging in direct consumer marketing and they are guilty of misleading consumers. I have also since learned that the tests are not even approved by the US Food and Drug Administration (FDA). With the big companies largely based in California, it is difficult to see how the will be held to account.


I had the nipt as I had very low Papp-a and my 12 week risk was higher than my age related risk. I have also read the ASAs rulings, and agree with everything you have said. I think there is a thread on here about nipt promotion which is very interesting. All the best with your little one. Enjoy the newborn bubble!! smile

Tqlina Sat 29-Aug-20 19:55:37

Hi @Aria2015
Please do not worry- I really hesitated about writing this post because I did not want to create more anxiety for moms. Everything can be so stressful as it is! I think people who get false negatives are also in a bit of a state of shock, so it is hard to talk about or write about. This happened to me a while ago-so my daughter is no longer a newborn but I am still very upset about the test.
The first time I had a 'no call' due to low fetal fraction (although it was not that low). But because I was not overweight, didnt have twins, etc. they just did a redraw and sent it off again. I have since read that 'no call' results can be a warning sign and it seems now that the recommendation is not to simply have another test but to do an amnio. Again, here I think the companies are misleading about this- because if everyone who has a 'no call' has to do an amnio, the rates of amnios will go up (defeating the purpose of NIPTs as an alternative to amnio), therefor companies prefer people doing redraws. This will become a bigger issue as more women have the test (and not just high-risk women).

OP’s posts: |
greytminds Sat 29-Aug-20 20:11:43

That must have been really hard to come to terms with. Please can I ask if you don’t mind - were the physical markers for Downs Syndrome subsequently picked up via ultrasound or was it a complete surprise at birth? Also, did you have the NHS screening as well as the NIPT or just the NIPT?

I know of a false positive rather than false negative - a high risk result for Turner’s syndrome that did not turn out to be accurate and since I have read up on how the test are not at all reliable for diagnoses outside the three main chromosome issues they pick up.

It strikes me from my experience of both infertility and pregnancy that once something gets commercialised, like the NIPT has, the ethics around it get murkier.

Tqlina Sat 29-Aug-20 21:09:34

@greytminds - it was a surprise. There were no physical markers and the screening did not pick it up either. I agree with you- test always has been commercialised and I think that there has never really been a proper debate about the ethics of it. The discussions are only just starting to happen but the companies are lobbying so hard - particularly in the US (and these tests are incredibly profitable). The regulations and broader understandings of these tests have not kept up.

OP’s posts: |
LBB2020 Sun 30-Aug-20 09:00:54

Congratulations on your baby and sorry you are feeling the way you are. We also had a postnatal diagnosis of Down syndrome following the birth of our son but we hadn’t had any of the screening tests as it wouldn’t have changed anything for us. I think the thing to remember about the NIPT tests is that they are only a screening test not a diagnostic test, there will always be the chance that you could be that “one” in however many hundreds or thousands! Congratulations again, I hope you are getting all the information and support you may need x

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