Miscarriage Question

[nuthinbutpink]

Hi Carole! I am not sure if this falls within your realm of experience but I thought I would try. When researching PGD and probes, I can across a site that had this info-


"Apart from these five chromosomes (13, 18, 21, X, Y), the only other chromosomes noticeably affecting the outcome of established pregnancies are chromosomes 16 (trisomy 16 found in 1,229 among 15,000 spontaneous abortions) and 22 (extra copy was present in 424 out of 15,000 spontaneous abortions). These embryos never reach term, but they affect the outcome of hurnan pregnancies.

Aneuploidy for any other chromosome is lethal at the very first stages of embryo development, before a pregnancy can even be established."

So, if I read this right, according to this center, outside of a 5 probe and chromosome 16 and 22, a pregnancy will never even establish? So, if one were to do a 5-probe(X, Y, 21, 18, 13), the only chance of miscarriage would be on 16 and 22? Any other issue on another chromosome will just not implant? Am I reading that right? Do you know this to be true?

Thanks and hope you are doing well!

[Carole]

Hi Nuthinbutpink,

This link might help: http://www.nature.com/scitable/topicpage/chromosomal-abnormalities-aneuploidies-290
When the products of conception are analyzed for pregnancy losses that occur in the first trimester, the most common aneuploidies are 45,x, 21, 16 and 22. Chromosome 16 is a very common early lethal chromosome. In stillborns, miscarriages that occur at 20 weeks or later, aneuploidies of chromsomes 13, 18 and 21 are most common. Livebirths are possible with aneuploidies on chromosome 13, 18 or 21 and the gender chromsomes (XXX, XXY etc). Other chromosome aneuploidies are even more lethal and so these aneuploidies are never detected in aborted tissue or later stages of development/birth. Hope this helps. :) Carole

[nuthinbutpink]

Thank you. Great link!

[twoboysandcounting]

Our first high tech loss was a 45x according to the POC report. The baby never developed, so I was told it was a blighted ovum. We had done Microsort and 2 probe for this pregnancy, so I wondered how it could be missing an X. If I'm understanding this right, the baby was missing one X, yet it was listed as an XX on our PGD report. Would mosaicism be the reason it looked like an XX but was really a 45x?

[Carole]

Dear twoboysandcounting,
I am sorry for your loss. I have to say that I really don't feel qualified to answer your question. My experience has been that most genetic testing labs have genetic counselors associated with them that should be able to answer questions about your test results. They owe you a clear explanation of what your results mean. Sorry I can't be of more help. Best Wishes, Carole.