Ozzie, as you know the baby is still tiny at 12 weeks and though all the ground work is done there is still much forming to do. The obs doing your u/s will not just look at your baby's nuchal fold but the nose, shape and other soft markers that are relevant. I stand by my comment that NT U/S married with bloodwork done by a well recommended foetal medicine obstetrician is extremely accurate. As Jac said the figures are around 85-90 percent accuracy - meaning in up to 90% of cases an abnormality is detected. In Franks case the percentage is higher. So, again it rests upon the operator. The higher the percentage the more comfortable you can feel with the result.

Yes, you will be able to pick up soft markers at your 19 week u/s if there were any. However, where this can be tricky is that if an accurate NT wasn't done there would be query as to weather the baby was at risk or not. To explain if you had a NT done by a specialist and you were given a 1:1700 chance of your baby having trisomy 21 you would also be then given a risk factor for other trisomies and that would be say 1:4000 (the others are less common). If you see the same specialist he may see something at your 19 weeks scan that were seen as soft markers but in comparison with your previous results it would lessen the concern - do you know what I am saying, or am I confusing??? If your risk was 1:200 and then at your 19 week scan there were soft markers the concern would be greater. The reason that the nuchal fold is helpful is that if you do want a definitive diagnosis then you can have CVS or amniocentesis if you decide this would be helpful to you.

I want to clearly state that NT U/S is not a definitive diagnosis however it is my belief that in the hands of an experienced foetal medicine specialist it gives a very accurate picture of what is going on for your baby... I would always suggest going to the same specialist to do your 19 week scan also - there is a measuring stick then.

Good luck Ozzie I have been thinking of you I do understand that the decision to have a peek at your baby is a big one. The whole prenatal testing debate can be emotional. to you and I look forward to hearing what you decide...