Hi Jess
I'm due on 19th feb, and had my NT about 10 days ago. I had a measurement of 2.2 and a combined probability of down's of 1 in 475.

Here's something that I read on a UK website:
What is nuchal translucency?

This is a collection of fluid under the skin at the back of a baby's neck at 10-14 weeks that can be measured using ultrasound. All babies have some fluid, but in many babies with Down's syndrome, the nuchal translucency (NT) is increased.

An NT scan is a method of assessing whether your baby is likely to have Down's syndrome. It's a screening test. A screening test can only estimate the risk of your baby having Down's, as opposed to a diagnostic test, such as CVS or amniocentesis, which will give you a definite diagnosis (but also carries a small risk of miscarriage).

The NT scan can't tell for certain whether your baby is affected. However, it can help you decide whether or not to have a diagnostic test.


When can I have the test?

NT scans are usually performed from 11 to 13 weeks + 6 days of pregnancy. Before 11 weeks the scan is technically difficult because the baby is so tiny and, after 14 weeks, excess fluid may be absorbed by the baby's developing lymphatic system.

What is a normal measurement?

An NT measurement of up to 2.0mm is normal at about 11 weeks, and up to about 2.8mm by 13 weeks and 6 days. This is because the NT normally grows in proportion to the growth of the baby. A baby with a normal NT of 1.3mm will be low risk.

If the NT is increased, it does not mean there is definitely a problem. Some normal babies have increased fluid, too. A baby with an NT of 2.9mm, which is at the upper limit of the normal range, will have a higher risk, but nine out of 10 babies with a measurement between 2.5mm and 3.5mm will be completely normal.

As the NT increases, so does the risk. A baby with an NT of 6mm and will be very high risk for Down's, as well as other chromosomal and genetic syndromes and heart problems. Fortunately, not many babies have as much fluid as this.
Sounds to me like, you have (a) been given some fairly inaccurate stats, 1-2mm is the range for 11wk pregs not 13 weeks, (b) you are not likely to be able to have another NT scan as the Nucchal fold dissappears at 14wks. (c) the risk of miscarriage is 1 in 200 and your risk is less than that. This means that the risk of the amnio is higher than doing nothing. And they should also have counselled you that unless you definitely are willing to consider terminating your pregnancy as a result of a negative amnio - don't have one. (d) had a technician who had a lot of trouble getting a measurement. The reliability of the test is entirely reliant on the accuracy of the technician. Banging your belly seems completely out of order. My technician worked with us for nearly 90mins to get our baby in the right place - all done very gently and professionally!

Good for you for sticking to your guns. If you feel your baby is fine then that's the best indicator. This is a horrible thing that has happened to you - I hope that the girls here can ease your worry a bit.

And why not come join us in the Bellybuddies for 15-28th Feb. We'd love to have you in there.