Do aneuploid embryos have any chance at all in a successful pregnancy?

Don’t they discard the ones that come back abnormal?

In Europe, you are not legally allowed to transfer an aneuploid embryo. In the US it’s your choice. An aneuploid embryon cannot not implant (unless it’s a false result which can happen 1-2% of the time)- there is no chance at all and it’s been proven by research.

Thanks Chrissy and Annia. Yeah they discard them. But I was just thinking if we do another cycle if we would want to do PGT-A again and it makes sense to do so if any aneuploid would definitely not lead to a successful pregnancy. I read some other articles that there is a small chance it could correct itself but maybe that's in the cleavage stage but not once it's hatched?

I’m not sure but I’ve been thinking about it also as if there’s a chance the “normal” ones are still abnormal then surely there’s a chance the “abnormal” ones are normal? Majority of my “normal” ones didn’t work so it’s been on my mind a lot 😔

The thing is it depends on the actual chromosomal issue they found, if it is an aneuploid, it could results in a successful pregnancy (many times it would not as many of the rearangements cause severe issues and incompatible with life), you would possibly end up with a child with a genetic condition and could have medical implications. So for example people who have children with Down syndrome - these come from aneuploid embryos, but the people didn't know because they got pregnant naturally and could not do PGT.

Hi you should get the raw data and get a second opinion on the results. Clinics vary on the threshold of abnormal cells to consider an embryo aneuploid. One clinic can say anything more than 20% abnormal cells is aneuploid and another can have a limit of 80% to be considered aneuploid. There is no universal standard 🤯. So if any of your aneuploids are > 50% or even less than 80% yes they are worth transferring. Another thought is that this second opinion and then finding someone to transfer an embryo that has been previously labeled as aneuploid will be time consuming and difficult, it might be better to do a fresh transfer without doing the PGT if you do another cycle? I’ve done 10 cycles and only 1 made euploids so happy to chat more if you’d like.

@Ana-LuciaThey only take 5–8cells. For the result to be euploid they all need to be normal. If only some are normal, then they’re classified as mosaic (you can have high or low mosaic depending on the % of normal cells). Also, a euploid embryo not implanting does not mean it wasn’t euploid. There are other reasons for euploid embryos to fail and the success rate is 50-60% for pgt euploid - not 100%. I personally would not see the value in transferring an aneuploid embryo. If you don’t feel confident in the test, then best not to do it. You don’t increase your overall chances by doing pgt, you only reduce your time to pregnancy by skipping transfers that are assured to fail or result in miscarriage.

@Annia my clinics genetic lab specifically told me that any results 0-20% abnormal were considered euploid, 20-50% abnormal were low level mosaic, 50-80% abnormal were high level mosaic and >80% abnormal were aneuploid. So this goes to the point that it’s really unfortunate that there is not a universal standard for rating embryos!

Yeah, and I got to know about segmental aneuploidy where just part of the chromosome is abnormal rather than the whole one, and it should be classified as mosaic. For ours, it was just classified as aneuploid. I think maybe it would be good to go with the higher standard as there is always a chance the lower standard has a higher chance of not being successful. I was watching this video the doctor said she saved countless of embryos that would have been discarded. It probably wouldn't change anything for me nor the outcome but good to know about the differences https://youtu.be/17vWAZwobfo?si=YceecANxsaDtlBYJ

@Ana-Lucia is there a minimum grading for your clinic to take in PGT testing? Mine said it's a minimum of BB otherwise they will discard and also not freeze the embryos.

Oh wow, that sounds super strict ! Are you in Europe or the US? My clinic certainly isn’t that strict. I had 12 embryos so there was a mix of grades and interestingly the euploid ones were not necessarily the ones with the best morphological grades! We froze all embryos with 5BC or 5CB or better. Some B/C were euploid giving them 55% chance according to my embryologist so I am happy they were not discarded.

Yeah exactly, some of the BC ones can be euploid and lead to healthy pregnancies too..so this is another consideration for me. Luckily all our blastocysts made it to the minimum criteria. We had 1 5AB, 1 5BB and 1 6BB but the latter two were both aneuploid (1 was the segmental aneuploid). I'm actually in the UK, our clinic is King's Fertility. What clinic do you go to?

I am with Fertility Plus in London. They work with Care fertility embryologists so Care policy applies when it comes to embryo selection. One factor that might influence your clinic policy might be the way they grade ? if their grading is ‘less strict’ that could explain why they discard below B?

That's a good point. I may check out other clinics. How's your experience with your clinic ?