First trimester tests- NT scan, CVS etc

I am confused a bit about these tests.

Let's say if I wanted to get the most complete panel of tests ( i am 31 yo), what would those tests be?

NT scan- 10-11 weeks? This is only based on blood test and measurements of the neck?

CVS-?? is it based on results of NT scan? This is based on liquid in placenta?

Amnio?

Also, what is the 100% way to rule out genetic disorders? ( if it exists)

Thanks

ETA. what is triple screen? same as NT scan?

Message edited 5/9/2011 4:23:30 PM.

Re: First trimester tests- NT scan, CVS etc

I had the NT scan at 12 weeks.
It was more than just the blood test and the neck testing though. They also measured all parts of the baby; kidneys, stomach, heart, liver, bones, spine, head, etc. so it was like a thorough almost growth sono as well.

I think some opt to have the CVS test based on age as well.
IDK why but I THOUGHT the CVS test was done in place of an amnio. But I could be TOTALLY wrong so don't even listen to me.

I don't know there is a 100% chance to rule out disorders but the CVS and amnio are close to it.

Re: First trimester tests- NT scan, CVS etc

Funny my friend who is 8 weeks & i just discussed this.

NT Scan is done at 12 weeks.

CVS is done at 10 to 12 weeks.

Amnio - is later at 20 weeks i believe.

NTScan is nto just bloodwork & neck measuring. It doe search for more. Make sure the stomach kidneys etc ar ein proper place. And at 16 weeks you will have another set of blood work for spinal bifida.

CVS is recommended for women over the age of 35. It would be done before a NT scan and as teh amnio has a chance of miscarriage.

I believe the CVS is given to give the parent an earlier option of what to do if God forbid the child has a defect.

Nothing is 100%. There will always be false positives in every thing. Good luck

Re: First trimester tests- NT scan, CVS etc

You'll have your NT scan at about 12 weeks. Not much earlier - they baby has to be developed enough so that they can check for what they're measuring for. You'll get a sono and blood tests, and they feed the results into a computer along with a questionnaire about family history / age / drug habits, etc. that you have to answer. Out pops a number, and that's your chance of having a baby with a birth defect. Anything better than 1 in 1000 is considered "normal" and they probably won't recommend you having any invasive testing (amnio, CVS) after that.

If the results are troubling, you can opt for a CVS right away or wait until you're 16w for an amnio. The advantage of waiting is that an amnio is thought to carry less risk of m/c, but the risk for both is about 1%-2%. Not something you'd want to risk if you're only 31 years old and your NT scan comes back normal.

I know it's so hard when you're worried about your , especially if you have a history of problems. But you'll have your NT scan first, and if it comes out normal, then trust your doctors and celebrate that it's normal. No need to subject yourself at such a young age to invasive and risky procedures, IMO.

Re: First trimester tests- NT scan, CVS etc

I opted for the CVS b/c of age (37). Since I opted for the CVS, I didn't even dot he NT with this one (I did for my others) I didn't even think about it for my first two (31 and 33). My OB told me that if we would terminate, the CVS was useful since you are not really showing yet, when you have to make the decision. CVS risks are very low. The numbers are skewed, since the rate of m/c, even without the CVS, is higher at 12 weeks than later in the pregnancy.

With a CVS they go through the vagina or the stomach (deoending where the placenta is) and scrape a bit of the placenta off and analyze the chromosomes. It does not test for NT disorders, so you would need to have another blood test for that later.

The amnio can happen as early as 15 weeks, if your membrane has begun to fuse (they need to puncture through the placenta - mine hadn't, so i had to wait until 17 weeks) I had to get the amnio after the CVS, b/c my placenta has an extra chromosome 12. Of course, with 12 there is a large percentage that it is confined to the placenta and not the baby. My amnio confirmed this. So while I had a good 7 weeks of waiting, it was still worth it since now i am stress free.

The amnio tests for chromosomes and NT defects (as well as other, I have skewed parvo results, so they tested for that as well.)

Re: First trimester tests- NT scan, CVS etc

thank you for your responses.

Re: First trimester tests- NT scan, CVS etc

I just want to add that most insurances will NOT fully cover a CVS or amnio UNLESS there is a reason for the test ie: age, abd blood work, genetic hx and so on. These tests are $$$$$. Check with your doc and insurance before hand.
In my OB practice a CVS is ONLY suggested if there are risk factors and you would consider termination for any abdnormal findings including down's and spinal bifida. If you would not terminate over that they do not offer the procedure unless the NT scan and blood is alarming.