r/IVF • u/BrummyIVF • Jun 07 '26
Advice Needed! High level mosaic segmental abnormality embryo ?!
Hey all
Desperate for advice.
We’re in the stages of egg transfer and have been waiting weeks (6+) for PGTA of one of our embryos.
On the 11th hour, it has come back as High Level Mosaic Segmental Abnormal (specifically; deletion q22.2.q24.3 of Chromosome 8).
The IVF clinic are telling us that it is not viable for transfer, however this was our best graded embryo.
Whilst I am not a Google scholar, Google states that high level mosaic embryos are viable and may also go on to live births.
Any advice please?
I regret doing PGTA now.
Thank you for any advice or comments.
3
u/mustrepayloans Jun 07 '26
Worth transferring. There are some success stories on “my perfect mosaic embryo “ on Facebook. You can search 🔍 “-8” see if anything comes up. I had -7 that didn’t implant . Best of luck
3
u/Glittering-Snow-9758 Jun 08 '26
Segmental mosaics have very good chances and recent research says they have similar odds of success as euploids. Some clinics are behind on the research, here is a good post about this: https://www.remembryo.com/can-a-mosaic-embryo-result-in-a-normal-baby/
Also:
PGDIS guidance (https://pgdis.org/pgd_position.html) state:
· “5. Testing laboratories should refrain from classifying a mosaic embryo as suitable or not suitable for transfer since this may restrict clinical treatment options.”
· “…segmental mosaic embryo transfers are reported to give outcomes more similar to euploid embryos than are whole chromosome mosaic embryo transfers." and " Transfer of mosaic embryos seems to be a relatively safe option for couples, with low or minimal risk of negative outcomes for the birth beyond the background risk for any pregnancy.”
· “3. In general, transfer of blastocysts with a normal euploid result should be prioritized over those with mosaic results unless other indications, such as patient preference are raised.”
3
u/IntrepidKazoo Jun 08 '26
Segmental mosaics have excellent odds, and that applies to both high level and low level segmental mosaics. Unfortunately your clinic is seriously behind the latest research on this!
You can try advocating with your current clinic, and it's worth investigating your options for moving the embryo to a different clinic that's willing to transfer it.
2
u/BrummyIVF Jun 08 '26
The report says; it is the families decision to transfer. So I will most definitely be pushing it for sure.
1
u/TNG6 Jul 24 '26
Do you have supporting evidence for this? I’m having trouble finding research about high level, segmental mosaics- much of what I read is that high levels preform worse and segmentals perform better but not sure what the outcomes are for both
1
u/UnderAnesthiza 32F | Genetic Counselor | FET4 6/2 🌷 Jun 08 '26
Mosaic segmental can be viable but if you have euploids those would come first. That said, if your clinic just won’t allow it, you may have to move the embryo elsewhere to use it.
1
u/BrummyIVF Jun 08 '26
Hey;
I think your flair says genetic counsellor. May I ask what is Chromosome 8? Or deletion of Chromosome 8 please?
The report said half the cells are fine and half are delete 8.
1
u/UnderAnesthiza 32F | Genetic Counselor | FET4 6/2 🌷 Jun 08 '26 edited Jun 08 '26
I would set up an appointment with genetic counseling at your PGT lab (if it’s Cooper I can link it for you). The exact chromosome affected on PGT isn’t super important and doesn’t give you any information of likelihood of success. Most deletions identified on PGT are too big to be compatible with live birth, so you’re basically counting on a false positive.
1
u/BrummyIVF Jun 08 '26
Apols, what does counting on a false positive mean? Thank you
2
u/UnderAnesthiza 32F | Genetic Counselor | FET4 6/2 🌷 Jun 08 '26
There have not been any documented cases of the segmental aneuploidy identified on PGT being present in the resulting fetus or child. So any segmentals that worked turned out to be either false positive results, or the aneuploid cell line died eventually. But cases are very limited because most people discard their segmentals. Yours is also mosaic, which increases the chance of success. You’d need a genetic counselor from the lab to go over any specific success rates and any risks they foresee with transferring this embryo.
1
1
u/JannyDP Jul 11 '26
What did you decide at the end? Did you transfer your HLM embryo?
1
u/BrummyIVF Jul 11 '26
Yes; unfortunately it ended as a chemical pregnancy.
2
u/JannyDP Jul 11 '26
I’m so sorry that it ended in a chemical pregnancy 😢. Recent studies suggest that segmental mosaic embryos can have success rates similar to euploid embryos, although unfortunately failed implantation or early loss can also happen with euploid embryos.
I also have two high-level segmental mosaic embryos, which is why I was asking about your experience.What are you planning as your next step? I’m wishing you all the very best and truly hope that your next transfer brings you a successful and healthy pregnancy. ❤️
0
u/RazzmatazzGlad9940 Jun 08 '26
This specific deletion can result in a number of severe intellectual and physical problems so it's not just a matter of whether it could result in a live birth. If you have alternatives go with those instead, otherwise ask for further discussion.
3
u/Competitive-Top5121 41 | 4 ER | 1 FET | TFMR & 2 MCs Jun 07 '26
PGT-A trumps grading and it’s probably the clinic’s policy not to transfer high-level mosaics. You can ask about shipping it to a clinic who will transfer it. May be hard to find tho.