PGT-A. How many blasts did you have tested?

[Keyu]

Hello guys, hope you are all well. Been trying to get some ladies opinions on this based on your experiences and could not find any thread on this.

We just completed 2nd cycle of a 3 cycle package.

If you had 8 blasts, how many would you PGT-A? We had initially consented to testing 5 but now worried because that what if they all return abnormal, we may loose the chance of every having a transfer from all these cycles.

So basically what would you do if you have 8 blasts? Or how many blasts did you test? What was your experience?

Thank you.

Well firstly how old are you, as that will determine how many will likely be euploid.

But either way if you've made a decision to test I would probably test all of them. My best graded embryo didn't survive the thaw and the next best one was my only abnormal embryo.

I was 36 - only had 2 and tested 2. Neither came back normal. One had to be destroyed as not allowed to transfer the other was a mosaic and I did transfer but BFN

Decided not to test any again and got 2 more blastocysts and had twins

I'm pretty sceptical of it to be honest - I know lots of people who tested 5-8 and got no normals and all were destroyed

I got 13 embryos across 3 banking cycles aged 41-42. Originally I planned to test about half, but ended up testing all. One of the embryos I (and the embryologist) would have left out based on grading alone ended up being euploid, so the selection process is tricky when judging on appearances. I got 2 normal and 3 high level mosaic out of 13.

If you only test half, look into how much it would cost to send a second batch off for testing at a later date. It’s normally cheaper to test them all together.

I would test all of them- because over and over I've seen stories of people's excellent/good embryos being aneuploid or mosaic and it being their lowest graded embryos that were euploid. If that happened with you, you could test 5 and just happen to land on all aneuploids or mosaics, which could maybe be devastating news to get- whereas actually you had euploids. I suppose then you could then test the last three (I'm assuming all had biopsies taken before frozen that are stored?) But might leave you longer in limbo or missing a planned FET depending on timing.

From what I understand, there is about a 1% or less chance of a false positive, and aneuploids will never lead to a healthy live birth. Low level or high level mosaics could do, but also most clinics will let you transfer those if you dont have any euploids. So there's really no risk of having nothing to transfer if you test them all, other than the 1% risk that they accidently false-positive your only euploid(s). If that makes sense?

Thanks all for your response.

@Gardenlady543 I am 40

@tiggerwhocamefortea wow! That is amazing and exactly my fear.

@IslandStars I agree, I will discuss the costs for the second batch with the clinic on Monday. We still have time to decide what to do.

@tulipsandsnow they all have biopsies taken. Embryologist says at the end of the 3rd cycle they will test the highest grade of embryos but I will have to give that some more thought.

Thanks ladies I appreciate all your input, very helpful.🤗

I read that aneuploids can result in a healthy baby www.nature.com/articles/s41556-021-00660-7

I haven't properly researched it, admittedly, and I'm sure the chances are small. I had 10 blasts to start with and only briefly considered it before taking my chances (eggs collected age 36). I figured we would spend less getting one to work than we would on testing (that was correct for us). If I were older, I might have made a different decision.

Hi OP - I also had all of them tested once I started on the testing journey. 2, then 1, then 7. I had three rounds before them from which I have three untested ones on ice (will cross that bridge if I have to in due course). But once I decided I was in it, we got them all done. I thought it was best to know completely where we were.

Good luck, hope your results are positive.

I joined a lot of online groups when I got my PGS test results and there are many many members who have had successful pregnancies from transferring abnormal, high level and low level mosaics and segmental embryos - it's much more common in the USA to be allowed to transfer them it's just in the U.K. you aren't allowed which hugely ups the risk of testing in this country

@Holskey thanks for study link!

The wording however, gives me pause, as they lump in 'mosaic and aneuploid' together when they say there were 9 pregnancies of the 32. The thing is, everyone knows that mosaics can correct/have successful pregnancies. The question is whether aneuploids can. With this wording, it makes me think all the pregnancies were from the mosaics, but it is confusing:
"To test whether mosaic human embryos develop normally, we report on 32 women who underwent frozen-thawed embryo transfers with 77 blastocysts that were diagnosed as mosaic and aneuploid by PGT-A. Nine clinical pregnancies were established (28.2%) from these transfers, 4 of which miscarried (44.4% of pregnancies, 12.5% of cycles), and the remaining ones were delivered (15.6%; Supplementary Table 1). ...Furthermore, successful cases of transferring diagnosed mosaic embryos have been reported [16,17,18]. Together, these clinical results unveil the developmental capacity of mosaic embryos, thereby supporting the possibility of a developmental rescue mechanism."

As you can see, the references they give for success are for 'diagnosed mosaic embryos' an even the last sentence summarising focuses on the capacity of mosaics and not aneuploids. I might be missing something but I can't find anywhere in the paper it explicitly says that an aneuploid pregnancy (vs mosaic) was successful in terms of an actual woman/observed outcome. The self-correction mechanism is interesting but again applies for the aneuploid cells within mosaics as far as I can tell?

Also, there's a very recent 2021 study, of only 201 embryos but pretty convincing in its results. Convincing because it was double-blind so absolutely no one knew which were euploid and which were not until much later when outcomes had already happened (live birth or not). 68% of the euploids led to live birth and 0% of the aneuploids did- I suppose it'd be more convincing if it had been 2,000 or better yet 20,000 instead of 200 embryos sample size, but still if aneuploids with any sort of decent frequency led to a healthy live birth you'd think maybe one of them might have slipped in that study!

This is all very enlightening 👀

@tulipsandsnow I didn't read the study 🙈 (I did say I hadn't researched it properly 😂). My egg collection was 2 years ago and I can't remember what I read at the time, so I just quickly googled it to check that I hadn't misremembered.

I agree though: from the excerpts you've posted, it's incredibly misleading! Unethical really given the difference between mosaic and aneuploid, and what it means to couples who've discarded aneuploid embryos.

Some links I looked back up that I'd book marked as good summaries. First one is objective summary, second one is strongly pro- PGT-A in most/all cases, but grounded in research.

First one points out that until 2016, different testing was used, so information that floats around that has its basis in studies before that year are pretty useless now (ie, its a LOT more accurate and less risky now- a lot)
www.reddit.com/r/infertility/comments/i72m79/faq_what_ive_learned_about_pgs_pgta/

perkinelmer-appliedgenomics.com/2020/06/09/data-supporting-pgt-a/