There has been evidence to suggest that the chance of the nuchal test showing false positives is very high.
There is a significant higher risk of m/c through amnio and CV, than there is that the test is accurate.

It still doesnt stop us stressing about the results, but just know that for everyone who gets a warning marker than something might be wrong from the nuchal test- most of the time everything is fine!

Hope this info helps and good luck!
odette