I just had my 12 week scan in UCLH! I was nervous to see if everything is okay, but I also tried to keep in mind that worrying won't change anything... I also kept reminding myself that statistically it's all most likely to be fine. As for the actual appointment, I kind of just go into autopilot when I'm nervous...
First they asked if I want to do the blood tests for chromosomal abnormalities to which I agreed. They took blood and asked me a few questions regarding my health (do I smoke/drink, family history of chromosomal abnormalities, etc).
If you would like to take a picture of the ultrasound home tell the sonographer before she starts. Also mine usually charges for it so take some cash with you (I don't know how much as in the end she forgot to charge me...).
Then we went to the 'table thingy' where I lay down and before I knew they already had the gel and then ultrasound device on my belly and within seconds we could see a little baby on the screen!! It felt very unreal and I started crying straight away and throughout most of the ultrasound :D (which the sonographer either didn't notice or tactfully ignored)...
I think the first thing the sonographer did after seeing the baby was recording the heartbeat. She then seemed to have a checklist on what she wants to see (quite a lot!), including both legs and arms, the brain, the heart, the spine, the bladder, blood flow, etc. For us that took quite a while as my baby kept moving around every time she tried to concentrate on something, and I kept thinking, oh no maybe it's not there, but we got there on the end
... She measured the length of the baby with which they will determine how many weeks/days pregnant you are and your due date. She also measured the fluid at the back of the neck to see if a chormosomal abnormality is likely and she'll tell you that straight away.
After the ultrasound they gave me the option to wait about 2h at the hospital for the results of the blood tests, or to go home and if they find anything to worry about they would give me a call before 6pm and then send a letter home. With the current weather I opted for the latter one
...
I think all in all the appointment probably took about 30minutes. And one more tip I read and did myself: drink about a pint of water an hour before the ultrasound, apparently that helps with getting the womb in a good position for the sonographer to see.
All the best!!! xx