If anything you see less as baby is more squashed the further on you go. What will they be looking at? If it's growth scans they'll measure the head and tummy so won't even be in that area. I had growth scans at 29 and 37 weeks and didn't see a thing - despite looking, couldn't help myself trying to peek!
Sorry, I had a scan at 34 weeks, we hadn't been able to find out the sex at 20 weeks, and by 34 weeks it was rather apparent (even to me and DH) that DS was a boy. Think they will have to be very careful or you will need to look away if you don't want to know (we did!)