Hi titti,
i'm so sorry you had to go through such an awful time with your last pregnancy and completely understand that you would want to avoid the entire situation. From experience (professional, not personal) it is a tough decision to make, and one that depends greatly on your personal beliefs.

Yes NT is a screening test and only identifies babies that are at a higher risk than normal, but it is also non-invasive and carries no risk to you or your baby. Many people choose to have this done because they a) would like the heads up that there might be something wrong or b) purely because it is available and they think they should or c) because if something was found to be wrong with the baby in later tests they would opt to terminate. I am planning on having an NT, just because if there is a higher risk i would like to be prepared for a baby that may have a disability, even though it would not change my approach in having the child. Others may find the wait and the rest of the pregnancy too stressful and hence opt not to have the NT, as they would not terminate if there was a problem anyway.

The beauty of an NT is that it is non-invasive. Amnio carries a <1% risk of m/c and i believe CVS has a 1% risk of m/c. Again this depends on the individual as to whether you want to know because u can prepare, or you want to know because you would terminate. Also, one must not forget that medical tests are not perfect.. a high risk NT may in fact be a completely healthy baby, a low risk NT may still have a disability, a positive amnio/CVS may be falsely positive and a negative amnio/CVS may not have detected a child with a disability.

at the end of the day, it is a very personal choice and difficult to weigh up. i probably have just added to your questions rather than helping you answer them. The best advise i can give is to find an OBGYN or midwife or GP who you trust and develop rapport with and whom you are comfortable discussing these concerns with. Then they can tailor their advise to your individual concerns/needs.

Good luck. I'm sure you will do the right thing for you.
xx