January 28, 2013


So...you remember when I made that nice little video with the colored blocks and explained what I had learned from the genetics counselor?  My chromosomes 7 and 22 were messed up, and when they paired up with my husband's we had a chance for unbalanced embryos.  I acted out four different pairings: normal karyotype (which is BabyGrok, completely normal 7 and 22), balanced translocation (which is me, part of 7 and part of 22 swapped, but all the DNA present and accounted for), partial 7 and extra 22 (which cannot become a human being) and partial 22 and extra 7 (not a human either).  So that means two options where I have a baby and two options where growth stops and I miscarry.  A 50/50 chance.  


And then I had 1 child and 6 miscarriages, which totally doesn't line up with that demonstration.


This always bugged me.  How could I possibly be so unlucky?  How could I have been told that I had a 30-50% chance for miscarriage and then go on to miscarry 86% of the time?  How was I such an outlier?  The universe must seriously hate me.


I even contacted the genetics counselor again and also Dr Carolyn Trunca, the leading expert on probability for translocations.  I begged them to look at my real-world data and explain to me why it didn't line up with the projections.  Both dismissed me and said I either had other factors at work or that I was counting pregnancies that weren't actually pregnancies.


And meanwhile, I just kept miscarrying.


Today I had a phone consult with the genetics lab that will be doing the pre-implantation genetic screening during my IVF.  And this genetics counselor said that the original tutorial I had gotten on translocations four years ago was entirely too simplistic.  There are not four possibilities, as I had illustrated with my colored blocks.  There are SIXTEEN.  Irregular DNA has a tendency to bend and contort and pull other DNA towards it and really make a mess of all the gametes.  So it's far more complicated than just a little 7 missing or a little extra 22; I can have eggs with a little extra 7, with a lot of extra 7, and with no 7 at all.  Sixteen different possibilities.


But still, only two of them can become human beings.


It's not known how likely it is for each of the possibilites.  It may not be that each possibility is equally represented.  But what PGD specialists see borne out by long-term data from women with recurring miscarriages due to a translocation is that the liklihood of having a child is really only about 2 in 16, or 12%.


And BabyGrok hit the jackpot: she has perfect 7 and 22.  She was the best possible egg I could've found.


We had about a 6% chance of finding that egg.


That is miraculous.


Now it feels like I went through hell to get her, don't get me wrong, but I stopped breathing when I heard the genetics counselor say that the odds of finding a normal karyotype egg are about 1 in 16.  I had been under the impression that BabyGrok was a 25% chance of happening.


She is far more miraculous than that.


So what does this mean for my IVF?  I know all of you mean well, but your stories of so-and-so who did IVF and was successful, that really is not applicable to me.  The odds of IVF working for anyone my age are at about 30%.  That's already lousy.  But that's people whose DNA are perfect.  14/16ths of my eggs are useless.


Let's say that the doctors can get my body to produce 16 eggs this month.  Statistically, only TWO of those should be able to become human.  But that doesn't factor in the normal loss at every step along the way during IVF.  A normal woman who doesn't even have to think about her DNA who starts out with 16 eggs is lucky to end up with 1 or 2 embryos during the process.  The odds of this working are really, really, really slim.  I feel like I know that, but I don't feel like most of the people around me are aware of it.  I feel like everyone is trying to tell me to stay positive and hope for the best and listen to this story of so-and-so who did IVF and has a baby.  I think I need to mentally prepare all of you for the fact that my odds are horrible.  I have to somehow find the 1 in 8 egg in there that has good chromosomes...AND get it to fertilize...AND get it to occupy my womb and grow.  This is probably not going to work.  I need you to be OK with that, and to scale back your expectations a bit.


It will be a miracle if we have another baby. 


Anyway, I knew that, but it felt good to have a medical professional confirm it in a nice and understanding way.  I can't explain how good it feels to have someone validate the crap sandwich that I have been served in the DNA department.  No, I am not some outlier with terrible luck.  No, the universe doesn't hate me.  My eggs are doing exactly what they're supposed to do with lousy DNA, and I always had a very slim chance of having a baby, regardless of how good or bad I thought my chances were.  I am completely normal for someone with a balanced translocation.  1 baby and 6 miscarriages is normal.


I have never felt so happy to get such crappy news. 


But Dr Trunca can suck it for telling me my odds were 17 times better than they really are.  She made me make irrational life choices based on numbers that were not realistic at all.  If I had been accurately informed that the odds of having a baby were only 12%, I would've done IVF two years ago and saved myself a lot of heartache.   But here we are...and wish me luck.  Because really, I'm gonna need it; probability is not on my side.  

Hold your breath.  I leave Wednesday. 

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