My wife is 28 years old and is in her 13th week of pregnancy. We had an NT test a couple of days back. The NT was 1.7mm. Trisomy 21 had an adjusted scale of 1:3428. Our doctor has advised us to go for a double marker test. The results will be out in two to three days. Is a risk of 1 in 3428 considered medium to high, to go for a blood test? Is there any relation between double marker test and NT? Is it possible that double marker test results may increase the risk from 1 in 3400s to less than 1 in 300? How are the results of NT and double marker combined? I know it is premature for these thoughts, but the anxiety in waiting for the double marker is killing my wife (and me). I thought of having a first cut understanding of how it works.