Hi Mumbot I've had it done 3 times-don't feel anxious! No internal scan , yes a date as well as that is part of how they calculate the risk for Downs and edwards syndrome and the other things- the most accurate results need a blood test too. only takes about 15 mins and then a few mins of calculations- i got my results immediately - i was private as its not available on the nhs here so it may be different in different places. Have someone with you though its always been a really emotional experience for me! Good luck!
You'll be fine, don't be worried. If everything goes well (which it normally does) it is quite an exciting experience as you get to see your little baby moving on the screen.
They normally do various measurements on the baby and can also take your bloodtest. The combined results of these measurements will then give you a statistical measure (this is by no way definate) of the risk of your baby having either Downs Syndrome or some other abnomality.
I had my scan at King's in London a couple of weeks ago and we ended up being there for 3 hours. About 30-45 min was just waiting time but I seemed to have a very active baby that refused to get into the right position for them to do the final measurement. They did do an internal scan on me as they thought they might get a better view from there (which didn't work) but eventually the little one finally co-operated. So the time it takes completely depends on the baby and how it is moving around. If the view is difficut with a normal scan they may suggest doing an internal one. It's not as bad as it sounds, a bit uncomfortable but not in any way painful.
They talked throught the result with us there and then so you don't have to wait.