Everything looked fine The nuchal fold which was measuring 8.3mm on Monday was now measuring 4mm on Wednesday. The specialist said that it was most likely an inaccurate measurment. When you're a certain way through pregnancy then the u/s wand has to be held at a specific angle to get an accurate reading. He did say the nuchal fold can be large and then reduce in size, but that's normally over several weeks, not two days.

Thanks for all the advice girls.