an update and a biology lesson

This is probably the last time I'll blog about this. Who knows, maybe not. But, I thought I'd let people know that we got the tissue test results back today from my miscarriage. We had the doctor send it away to be analyzed so that we might figure out the cause of the miscarriage in case there was a chance we could do something to avoid it happening again.

The analysis shows that we had a trisomy 15 fetus. If you've had a biology class or two, you know what a trisomy is. If not, in a nutshell, it means that either the egg or the sperm, when it was formed from another cellular division, ended up with an extra copy of this chromosome. (You are supposed to get 1 copy of each chromosome from each parent.) Then, when the two cells combined, you have 2 copies + 1 copy = 3 for the trisomy. So, any cells produced from that combination will now have the extra copy. (Down syndrome is trisomy 21.) If you want a detailed biology lesson, click here for a good description. (sorry - the biology teacher in me is coming out now...)

Trisomies are probably the most common reason for a first trimester miscarriage. Most people just don't know that's what caused the miscarriage. It's just a mistake in cellular division and happens randomly. Some trisomies produce viable embryos that can develop and live on their own once born, like a Down syndrome baby. Others are completely lethal. Complete Trisomy 15 is 100% lethal. (there is also a mosaic trisomy 15 where only some of the fetal cells have the extra copy and those babies can be born and live.) Other trisomies have a spectrum of viability, like our friends who delivered a Trisomy 18 baby who was born at full term and lived for 23 hours last year, while others with that trisomy might live a few weeks or months or years. (ps - I am not an expert on the trisomy outcomes, but this is what I have learned from what my doctor has told me and from a little research online.)

When they do the analysis, I know that they also learn the chromosomal make up for whether it was male or female. When the doctor called today, he didn't offer that information. I was tempted to ask, but I decided not to. I don't really need to know and I don't really want to know. I've lost enough already and to know if I lost a boy or a girl will make it even more personal and hard to get over.

I did really want to know the cause and now I do. It feels very relieving to know that the problem was there from the very beginning and there is nothing that I did or that I could have done to cause or prevent the outcome. It also means that any future pregnancies have every chance of being normal that any pregnancy would. This was a random occurrance and has nothing to do with my health or activities or ability to keep trying. So, whew. We will keep trying!