Possible Down's Syndrome after PGT-A testing

[Systema23]

Hi all

Looking for some advice from someone who has gone through the same or has knowledge of it.

I am currently 18w5d pregnant with an IVF baby. I underwent PGT-A testing as I am 41 years old. I thought that with PGT-A testing, that all Chromosomal abnormalities would render the embryo aneuploid, and thus I would not be allowed to transfer and as down's syndrome; Edward's syndrome and Patau Syndrome were a result of a missing or extra chromosome I wouldn't need to worry about them.

My midwife called today and advised that my blood test showed a higher-chance result and I need to go in tomorrow for a NIPT blood test. That has thrown me, as I thought this late on I wouldn't need to worry.

Has anyone had experience of PGT-A testing and can it miss Down's etc, or am I worrying over nothing?

I was told the results would take 7-10 days to come back and I don't think I can handle the wait. Any insight would be appreciated.

[Football61]

Hi. I carried out two IVF cycles with my own eggs last year and sent all the embryos for PGTA testing. I’m no expert, but I thought that the testing picked up chromosomal abnormalities - which could possibly lead to Down Syndrome, etc (although I guess no test is ever 100% conclusive). Could you contact the embryology team at your IVF clinic first thing tomorrow morning to inform them about your blood test - and ask them to talk you through the PGTA results for the embryo you transferred? I think that’s what I would do. Please G0d you have nothing to worry about - it’s good that you did the PGTA testing. Wishing you the very best of luck (and huge congrats on your pregnancy) - let us know how you get on ❤️

[Systema23 in reply to Football61]

Thank you and I will

[Kate-92]

I would like to think that the PGTA testing would absolutely rule out the 3 main trisomies alongside others otherwise why pay such an expense if I didn’t ? I agree with contacting your clinic and asking them for some further advice.

The blood test you have been contacted over, was that your 12wk screening bloods ? Or another? When they get your results everything is put into a computer which then throws out your odds - age will always sku that.

We didn’t have our embryo PGTA tested but we did have the screening, and also opted for a private NIPT.

Congratulations on your pregnancy & please let us know how you get on 💞 x

[Systema23 in reply to Kate-92]

It was meant to be the 12 week test, but they couldn’t fit me in till 16 weeks for my booking appointment so the test was done in week 18.

I have left a message at IVF clinic but waiting for someone to get back to me.

[Kate-92 in reply to Systema23]

so it will be from the NT & the screening bloods and as someone else has said that won’t take into account the testing you have already had. I am sure all will be well 🙏🏼

my NIPT came back in 3 working days, the time frame they have given you is probably worst case scenario x try to keep yourself busy & I know it’s hard but don’t google… you’ll end up down alkinds of rabbit holes ! There’s always more negative than good x

[Saskia9]

I didn't have PGTA testing but after my Nuchal scan and bloods the said I have a higher risk for Downs so I did NIPT also and it came back as very low risk. My friend had a risk of 1:25 but the amnio showed everything was alright. I wouldn't worry since you had PGTA, the program they use to calculate the risk probably doesn't take to account that you did PGTA.

[Mudra85]

Hi Systema,

I'm sorry you're having to go through this worry despite having PGT-A testing.

Here's what I know. PGT-A testing is not 100% accurate. No test ever has a perfect level of accuracy. However, incorrect diagnoses with PGT-A are very rare. The test you have had, which I believe is the nuchal screen, is less accurate than PGT-A, so it is more likely that the nuchal screen is wrong rather than the original PGT-A result. Like another person here has said the nuchal test also takes into consideration your age as well as your blood/scan screening test results to estimate the probability that your baby could have down syndrome, which may falsely increase the chances of this actually being the case.

The wait for NIPT testing won't be nice, but it is also more accurate than the nuchal screening you've had and will most likely confirm the original PGT-A diagnosis you had for the embryo you had transferred. There is obviously a chance that you could get bad news, but from everything I've read this outcome is extremely rare.

The other thing you could do is ask your clinic or better still the lab that does the PGT-A testing for your clinic whether they've ever known any of their patients to have had an incorrect PGT-A diagnosis after transferring an embryo. They should be able to give you their stats on this. This may help you to understand the real risk of this happening and provide a little reassurance whilst you wait out the results of NIPT.

Keeping everything crossed that this is just a false alarm and all will be OK for you. X

[Systema23 in reply to Mudra85]

Thank you x

[Eternalwarrior]

Hello lovely

I am so sorry you are going through this. My son is nearly 2 years old and was the result of the transfer of an euploid embryo (PGT-A tested). My 12 week scan came back as very high risk for Down’s Syndrome. I had a very complicated pregnancy and also complicated obstetric history (lots of miscarriages and my older son born sleeping at 18 weeks) The consultant in fact was pushing for me to have an amniocentesis and I just refused to do it. I had the NIPT and it came back low risk and my son was born healthy with no issues. They say that PGT-A testing is not 100% but my IVF clinic said it is extremely rare they make a mistake, especially for Down’s Syndrome. My NIPT results came back in a few days and they were low risk. I hope the waiting is not too long and you have a smooth rest of your pregnancy. Xx

[Systema23 in reply to Eternalwarrior]

Thank you so much for your reply. I managed to speak to my clinic and also another midwife at the hospital who basically says the same thing.

I am hoping the wait will not be too long.

[Cinderella5]

PGT-A testing is fairly accurate....although with everything medical nothing is 100%. You are right, the chromosomal would show up the extra trisomy for 21. My gut feeling is that your age is probably going against you. Sorry I don't mean that in a rude way....its just a risk calculator that inordinately your age goes against you.xx

[Systema23]

hi

Not being rude at all, once I managed to speak with a more experienced midwife, she basically said the sane thing as you about age, which is reassuring. Just really wanting those results to come quickly now. Xx

[MrsOrangejuice]

I don't know about the genetic testing but the initial odds are based quite heavily on age. My first was an IVF transfer and they used the age I was when the embryo was created (36) and that came back medium risk, then this time it's natural and conceived at 39 and the initial risk was assessed as much higher. Both times when they got the bloods back and did the recalculation the risks dropped massively - to pretty much the same odds as if I was 25! It's a bit of an anxious wait while they do that recalculation but hopefully if you've had the genetic testing you're actually in a better position than many women.

[PineappleCrumble]

I am sure as others have said, that your age has skewed the algorithm, this is a huge factor in the probabilities they give. And the fact you had PGT-A means it's unlikely that your baby has Down's Syndrome.

My baby is extremely likely to have Down's Syndrome, based on the 12 week screening and subsequent NIPT. I didn't have PGT-A though. So if you do come back as high risk, feel free to reach out.

Whatever happens, sending you best wishes. x

[Systema23 in reply to PineappleCrumble]

Thank you so much. X