Ghost, PGS Results - Mosaic

[chonda]

Good morning,

I just received my PGS results and have 1 mosaic embryo. It is up to me to transfer or not so I wanted to hear your thoughts. The other 2 tested embryos were abnormal. My past 2 cycles with PGS resulted in 1 no result embryo (out of 12 tested), which ended up being retested and normal and now I have a healthy baby girl.

Any advise for the mosaic embryo would be greatly appreciated. Also, what are your thoughts on trying again, in hopes for 1 good embryo? I am 40.

Thanks

[Ghost]

What is the nature of the mosaicism? Which chromosomes? Do they suggest trisomy or monosomy?

This is all too new to give out any solid or proven advice. However, I would consider transferring it if the mosaic results do not suggest trisomy in chromosomes 13, 18, or 21, or any aneuploidy in the sex chromosomes. That way, in theory, the worst that can happen is a failure.

Mosaic results are fairly common. Live births of healthy infants have been achieved with some embryos with mosaic results. The data are very sparse, but it seems the chance of live birth with the transfer of a mosaic embryo is perhaps in the 10-30% range.

Richard Scott (a leader in this field) argues that most mosaic results are actually normal embryos. Others argue that abnormal cell lines in the embryo tend to die out, leaving only the normal lines to become the infant (that might apply to most aneuploidies, but not those few I specifically listed above), or maybe the cells we biopsy from the trophectoderm tend to be worse that those in the inner cell mass. Maybe. The inner cell mass, by the way, becomes the infant, and we don't sample those cells.

You raise another important point. At age 40, time can be critically important. Your ovarian reserve can be declining rapidly. That's an even bigger factor if you are hoping to have multiple children.

I hesitate to give advice on what to do, but I have told you generally what I know.

[chonda]

thank you so much for your response.

my results state Mosaic Monosomy 22.

Please let me know your thoughts. Does this mean I should use this embryo?

[Ghost]

Does this mean I should use this embryo?

Maybe... The transfer of known mosaic embryos is very new.

Consider the following:

If the embryo is actually normal, it will give you a good chance of live birth.

If the embryo is actually monosomy 22, it cannot achieve live birth. A pregnancy loss, maybe, but you will not end up with a monosomy 22 child. Monosomy 22 is not compatible with life.

If you had not opted for genetic testing, this embryo would have been transferred. It seems almost certain that thousands upon thousands of embryos have been transferred that would have had mosaic test results had they been tested like yours was.

[chonda]

If I get pregnant and miscarry, will the miscarriage happen early on in the pregnancy?

[Ghost]

Typically, yes. But reliable data have not been published for each specific aneuploidy. I don't know when, on average, monosomy 22 aborts. I believe nobody knows this, but I might be wrong.

Keep in mind, the mosaic result suggests no more than half of the sampled cells were aneuploid. Also, the biopsy is always in the trophectoderm, never in the inner cell mass, or ICM. It's the ICM that becomes the baby, and that is not sampled.

[chonda]

Would you recommend transferring a mosaic? or trying again in hopes of a "normal" embryo? I do not have insurance coverage. I am 40. My last cycle resulted in 7 abnormal, and one no result, which was retested to normal and now i have a dd. The cycle prior resulted in all abnormal embryos.

[Ghost]

I try not to post medical advice. Just information.

[cloudberry]

I can very much relate to what you are going through, as I am facing the same question. I have 16 abnormal embryos and one mosaic that is feasible for transfer. I am also the same age as you. Having gone through an endless number of cycles producing only abnormal embyos, I will now need to decide whether to proceed to donor eggs or give the mosaic embryo a chance. While your post is fairly recent, I was wondering if you have already reached a conclusion? So sorry that you too are in this difficult situation, hopefully everything will work out well very soon!

[xenia]

I'm not medically trained, but from what I have read PGS NGS is recommended for women who experience msc or failed IVFs to implant only healthy embryos.

[Ghost]

Mosaic embryos are a tricky question at this point. There are very few published reports of their outcomes, and there may be reporting biases. For example, a clinic that saw birth defects after transfer of a known mosaic embryo might be reluctant to report their potentially poor judgement. Maybe. I do not know.

If all I had was a mosaic embryo in my own cycle, I might transfer it. I am not sure. It depends on the nature of the mosaicism. Trisomy 13, 18, or 21? No way. Same for aneuploidies in the sex chromosomes.

But monosomy in chromosome 1, for example? That's probably safe. Probably. No monosomy like that can achieve live birth, or so I understand.

[Gia9]

Mosaic embryos are a tricky question at this point. There are very few published reports of their outcomes, and there may be reporting biases. For example, a clinic that saw birth defects after transfer of a known mosaic embryo might be reluctant to report their potentially poor judgement. Maybe. I do not know.

If all I had was a mosaic embryo in my own cycle, I might transfer it. I am not sure. It depends on the nature of the mosaicism. Trisomy 13, 18, or 21? No way. Same for aneuploidies in the sex chromosomes.

But monosomy in chromosome 1, for example? That's probably safe. Probably. No monosomy like that can achieve live birth, or so I understand.

Can't agree more, it's apparently still under a lot of RND. Hard to take the call really if you should go for the FET with the mosaic embryo. However, on a second thought as long as it's not 13,18,21 trisomy you can actually take a chance. You don't have any leftover frosty and will probably have to go for a fresh IVF cycle so why not go for it. It's just my personal opinion though.