Friday, August 24, 2012

Meiotic non-disjunction strikes again

After a great deal of haranguing, I got the results.  Meiotic non-disjunction (which, in English means, the chromosomes did not separate properly during the process of making an egg or sperm) has happened again.

During my second pregnancy, it happened in the form of a monsomy of the X chromosome, which means either the egg or sperm had one less X chromosome that it should have. Monosomies are considered to be more likely a sperm error (a sperm that is missing a chromosome is lighter, can swim faster, yada, yada).

This time, it was most likely to be an egg error- a Trisomy, of chromosome 4. And it was a girl.

On googling, my blood ran cold- trisomy 4 appears be one of the rarer ones, and more often its a partial trisomy, (you have a 3rd copy of only one half of that chromosome) and the child can make it to birth, but obviously, with major, major issues. Thank god  my baby and I was spared that. Often, miscarriage is not about nature being cruel, its about nature being kind, and nature was kind here, but only AFTER the bloody trisomy had resulted. Bloody nature.

I'd had a bad feeling about this pregnancy from the time that the first beta and progesterone values had come in, because they were both far lower than my levels for the first 2 pregnancies (though, in normal range for the population) and the progesterone fell sharply by the 7th-8th week period-this was all in keeping  with the observation that some (but not all aneuploidies) can have lower progesterone and beta-HCG levels. Its fascinating, apparently trisomy 21 has higher HCG levels, but Trisomies 13 and 18 have lower progesterone and beta-HCG levels---wow, this suggests that complex mechanisms behind aneuploidy of different chromosomes, just because we don't understand it in the slightest, does not necessarily mean that its completely random. Chromosome 4 aneuploidy has not been studied, because its too rare, but my scenario also points to reduced hormone levels with this one.

What next? IVF with PGD obviously, but I'm trying to end up with a method more accurate than FISH, which does not analyze all the chromosomes, and would (probably?) have not caught this one.  The goal is to get microarray done with IVF in India-- this one has several logistical issues, lets see how they can get worked out. 

But as for now, I'm so very glad to have an answer. The point where we get grateful for small mercies is a sad one indeed.

12 comments:

  1. Answers aside, I'm just sorry again you've had to go thru the pain & hurt. I hope your road to IVF goes smoothly.

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  2. I was inspired by your last post to make the follow up appointment with my OB to find out what happened with my last pregnancy. I'm so sorry you are going through this but you are tackling this problem as the logical smart scientist you are. Thank you for sharing your journey.

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  3. I am glad they finally sent you the results.   IVF sounds promising in light of these facts.  Like Tiara, I hope it goes smoothly.

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  4. Glad you got your answer.  Wish it didn't have to happen the way though.

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  5. Ugh, Jay - I'm still so sorry you miscarried, but am glad you got a solid answer as to what happened. I think IVF with microarray is a great idea...of course you know that is what finally worked for us. we threw in an origins of aneuploidy test at the same time to determine whether our aneuploidies were sperm or egg driven, which was useful to me, emotionally more than anything.

    As for the error being on Chromosome 4...my understanding from talking to our genetic counselor about this is that the low number chromosome errors are rarer, but only because they are such large chromosomes (as compared to say, 21) that they often don't make it even to blast stage....that's likely more the case for huge chromosomes like 1 and 2, but i think when there is a full trisomy on 4, it just doesn't grow so far. mosacism is a whole different ball of wax, as you stated in your post.

    anyway, i really hope getting more answers helps with the healing and the figuring out how to move forward. 

    thinking of you.

    Mo

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  6. It's good to have a definitive answer.

    We did CGH on our two donor cycles - allowed us to biopsy on Day 3 and get results by Day 5.

    We did FISH on an earlier cycle and transferred a 'normal' embryo that didn't implant. Found out after that FISH-normal only gives you a 50% chance of an actual normal embryo, so I insisted on full chromosomal testing after that.

    I have a post on my blog with sample results from both types of testing, if that's helpful.

    Good luck!

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  7. I'm glad you got some answers.  I know that not knowing is very hard.

    I was wondering if you have ever considered using (or have used) a different donor.  I know that there are healthy children out there from his sperm, but I always wonder about the idea of somehow a certain person's egg and a certain person's sperm being incompatible (not very scientific, I know).  This train of thought leads some women to change donors if they are having trouble after a few times.

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  8. I am glad you got some answers but I am so sorry you had to go through this in the first place.

    I pray that IVF with PGD is the answer!

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  9. I'm glad you received your answers (finally).  It sucks that you have had to deal with this repeatedly.   It sounds like IVF with PGD is a good choice.  Still thinking of you

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  10. Thinking of you.  My heart bled when I read your comment:  "The point where we get grateful for small mercies is a sad one indeed".   So very true. 

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  11. Thinking of you Jaya.  Hope all went well with the move and looking forward to hearing about your IVF cycle in the near future.  

    Hugs from Michelle & Chase.

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  12. I am so so sorry for your losses.

    I had an embryo with a Trisomy 4, however we learned about it after CCS testing, and not a miscarriage.   My doctor confirmed it's a rare trisomy too.  

    Have you looked at RMA of NJ for CCS/PGD/CGH testing?  I ask because rumor has it CCRM sends all their biopsies there anyway.

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