The scoop on genetic testing (16 weeks)
OK, so another fun thing about being pregnant is all the tests you take! Once you've passed the pregnancy stick test, then you take a blood test just to make sure. Then, every time you come in to your doctor's office, you have to give them a sample of urine to test proteins. I also took an early glucose test, which consists of drinking a very sweet orange substance (tastes like flat orange fanta) and then having your blood drawn an hour later. Apparently I get to repeat this in my third trimester as well.
But the biggies are the genetic tests. As some of you my age might know, 35 is some kind of magic number - your doctor starts issuing stern warnings about perhaps trying to get pregnant as you near this deadline. This is because of a numbers game, it turns out. The odds of having a child with a chromosomal anomaly increase substantially once you hit 35 and keep going up, to the point where sometime after 40 you literally have a 20% chance. I guess our eggs, which of course have been inside us since before birth, can decay over time, so the last ones in the bin are more likely to be rotten, so to speak. The reason they want you to do this at 35 is quite simple: The risks of miscarriage due to an amnio are around 1 in 300, and the risks of having a genetic anomaly at 35 rises to 1 in 300, so suddenly it's even odds, making it more worth it to do such a test.
They used to just do amnios on everyone, which consists of inserting a needle into the placenta and withdrawing amniotic fluid at around 17 weeks. However, being at 16 weeks I can tell ya, it really doesn't seem like there's lots of room in there for that, although I'm not opposed to the procedure. In fact, Mike and I had just planned on it because we wanted to be pretty darn sure we didn't have an extra chromosome, which can not only result in Down's Syndrome, but also trisomy 13 or 18, which cause severe retardation and infant death.
But in the last few years they've developed some other less invasive tests, which I've been doing. A blood screening for proteins combined with a "nuchal translucency", which is basically measuring the back of the neck of the fetus at ~ 14 weeks can give you some adjusted odds. If those odds are very high, they can do a CVS, which is where they insert a tube through your cervix to take some stem cells to test (yeah, that doesn't sound pleasant). If they're borderline they will schedule you for an amnio. If they're low they will just have you come in at ~ 17 weeks for a "quad blood screening". But the only thing is that the less invasive tests will miss a little more than 10% of the extra chromosome problems because they are not genetic tests.
So again, we were just planning on the nuchal to get an early warning if needed, but also planning on the amnio to be sure. But after I went in and had the nuchal ultrasound (which by the way you have to do with a full bladder, and then they tap your belly for 20 minutes to get the baby to move in the right position...ack), they told me my odds were 1 in 96000 of having trisomy 18 and 1 in 5500 of having Downs Syndrome. Now while I'd love to be SURE, at this point the risks of an amnio are still 1 in 300, so as a logical numbers person it really no longer makes any sense. So I'm just going in for the quad screening next week.
I realize all that was probably not super exciting, but hopefully informative - and for those of us in California, the state subsidizes all this testing if you're over 35!
Next up - second trimester - Am I really pregnant or is this an elaborate hoax?? :)
But the biggies are the genetic tests. As some of you my age might know, 35 is some kind of magic number - your doctor starts issuing stern warnings about perhaps trying to get pregnant as you near this deadline. This is because of a numbers game, it turns out. The odds of having a child with a chromosomal anomaly increase substantially once you hit 35 and keep going up, to the point where sometime after 40 you literally have a 20% chance. I guess our eggs, which of course have been inside us since before birth, can decay over time, so the last ones in the bin are more likely to be rotten, so to speak. The reason they want you to do this at 35 is quite simple: The risks of miscarriage due to an amnio are around 1 in 300, and the risks of having a genetic anomaly at 35 rises to 1 in 300, so suddenly it's even odds, making it more worth it to do such a test.
They used to just do amnios on everyone, which consists of inserting a needle into the placenta and withdrawing amniotic fluid at around 17 weeks. However, being at 16 weeks I can tell ya, it really doesn't seem like there's lots of room in there for that, although I'm not opposed to the procedure. In fact, Mike and I had just planned on it because we wanted to be pretty darn sure we didn't have an extra chromosome, which can not only result in Down's Syndrome, but also trisomy 13 or 18, which cause severe retardation and infant death.
But in the last few years they've developed some other less invasive tests, which I've been doing. A blood screening for proteins combined with a "nuchal translucency", which is basically measuring the back of the neck of the fetus at ~ 14 weeks can give you some adjusted odds. If those odds are very high, they can do a CVS, which is where they insert a tube through your cervix to take some stem cells to test (yeah, that doesn't sound pleasant). If they're borderline they will schedule you for an amnio. If they're low they will just have you come in at ~ 17 weeks for a "quad blood screening". But the only thing is that the less invasive tests will miss a little more than 10% of the extra chromosome problems because they are not genetic tests.
So again, we were just planning on the nuchal to get an early warning if needed, but also planning on the amnio to be sure. But after I went in and had the nuchal ultrasound (which by the way you have to do with a full bladder, and then they tap your belly for 20 minutes to get the baby to move in the right position...ack), they told me my odds were 1 in 96000 of having trisomy 18 and 1 in 5500 of having Downs Syndrome. Now while I'd love to be SURE, at this point the risks of an amnio are still 1 in 300, so as a logical numbers person it really no longer makes any sense. So I'm just going in for the quad screening next week.
I realize all that was probably not super exciting, but hopefully informative - and for those of us in California, the state subsidizes all this testing if you're over 35!
Next up - second trimester - Am I really pregnant or is this an elaborate hoax?? :)