Danni - your ob is doing the right thing. Apparently the NT test is best done as close to 13weeks as possible. It can be done any time between 11w and 13w6d but 13w is the best time.

I nearly went out of my mind waiting for the scan! In the end I asked to have it at 12w5d because otherwise a longweekend would have meant I had to wait another 7 days for the results. By moving it two days earlier I got the results in 2 days instead. Hang in there Danni - I know how nerve wracking it is.... and then once you are through it you can loosen your straightjacket for a little while and relax!!!