Don't Know Why

As we have shared the news of Jellybean's heart issues with people, we've have two main questions:

1)  Is it the same thing Lil' Bit has?  No.  If it was, doctors would be writing this up in medical journals right now.

2)  Do they know why both your kids have heart issues?  No.  There are lots of factors that can play a role in children getting congenital heart defects (CHD).  Below is our best understanding of some of those risks and why don't seem to be applicable.

Family History
This is generally the biggest factor, hence the big jump in probability of Jellybean having a heart defect once we discovered Lil' Bit had one.  However, to the best of our knowledge, there are no cases of a CHD anywhere in either my or Phil's family.  So, although Lil' Bit's having one increased the chance Jellybean would also have one, Lil' Bit had no increased risks.

Anti-depressant Use
First, an interesting fact:  The fetal heart is fully formed by roughly 7 or 8 weeks gestation, which is generally long before most people know they are pregnant.  Thus, things that occur later in pregnancy have no bearing on whether there are CHDs.  However, because I was taking my anti-depressant prior to and during that time period, and there is a link between the anti-depressant I have been taking and babies having CHDs, we were concerned about this.  However, the drug I took (my doctor just switched me to something new) is linked to a very specific type of defect which Jellybean doesn't have, and I didn't take any anti-depressants during my pregnancy with Lil' Bit.  I have had at least seven different doctors reassure me that this was not the cause.

Uncontrolled Diabetes
Children born to women whose diabetes was not well-controlled are statistically more likely to have a CHD.  However, because my diabetes is gestational, it is less-likely to be the cause of any issues.  My doctors reassured me this is generally applicable to women who are diabetic pre-pregnancy.  In addition, my A1C test at 3 months gestation revealed a nice low average blood sugar level of like 5.5 (well in the normal range).  Because this test provides an average blood sugar level for the prior 3 months, to the extent that there was any chance I had diabetes prior to pregnancy, it could not even remotely be considered out of control.  This was not the cause of either child's CHD.

Chromosomal Abnormalities
There are lots of chromosomal abnormalities that are associated with CHDs and, because I was 34 at the time the embryos were created, my kids were at a slightly higher risk of such abnormalities than if I had been younger.  Because we are unwilling to risk a miscarriage to have an amniocentesis done, we won't know until after Jellybean is born whether he has any such abnormalities.  We do know, however, that Lil' Bit doesn't have any and, because her embryo and Jellybean's were created at the same time, there is no additional risk for him based on my increased age during his pregnancy--the risk is calculated based on the age of the egg, which was the same for both kids.

This is the biggy, and it's somewhat controversial.  Initially, there was a fair amount of research that indicated a link between IVF, particularly with the use of ICSI, and CHD.  Subsequent research indicated that the increased correlation could be because of the increase in multiples (twins, triplets, etc).  Other research has shown that although there is an increased incidence of CHD among IVF users, it is because there is an increased incidence for couples who suffer infertility, regardless of the fertility method used to conceive.  Thus, whether Clomid, IUI, IVF, or natural conception after years of infertility, the incidence rate appeared correlated with infertility, not IVF.  We had seen this research and thought that since our infertility issues were largely structural--the result of blocked tubes from a ruptured appendix--rather than genetic or hormonal, we had a lower risk.  Guess not.  In any event, the current understanding is that children conceived using IVF do not have an increased risk of developing a CHD.

So, there you have it.  The only risk factors for CHD that might have some application in our case appear not to be the cause.  And, in truth, I'm not sure it really matters what caused it.  If it turns out I did something to cause it, would being able to beat myself up about it change anything?  No.  Would pointing the finger at IVF help?  No.  I think we would have made the same choices because the odds of any child having a CHD are just so darn small.  So, to the best of our ability, we're setting aside the need to know why it happened and just focusing on what we do from here.  It seems like a much better use of our limited physical and emotional resources right now.

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