coco (and anyone else who is interested). Today's consultant appointment was good.
I read my letter last night which was good as I had forgotten I needed to take a sample with me.
When I got there, I met with a mw, who took my blood pressure, tested my wee for sugars and I heard the heartbeat - I wasn't expecting that! 
She was asking generally how I'm feeling etc. she filled in a page on my notes and then went to update the consultant in the next room (which seemed to take forever)!
I then went to see consultant. He explained that had been referred due to high bmi and thyroid problems (which I knew). He explained high bmi leads to a higher risk of diabetes (which I knew) and therefore I would need the GTT at 28weeks (which I knew). He asked about my medical history. Due to my weight, and my history with my back, he has referred me for an anethatist appointment at the hospital. So they can look at my MRI and weight distribution on my back and work out whether I can have an epidural or not (second mw in the room explained that it's easier for them to do this assessment before I am in labour, as I may be a wriggling mess by them). I'm actually hoping I won't have to have one, but this seemed irrelevant today.
He also asked that I get booked in for 34week growth scan (as apparently bump measurements can be inaccurate if there's a lot of "you" affecting the tape measure) (fairly comically phrased I thought! ). this will be followed by my second consultant appointment. (I presume to assess the results of the ultrasound).
He offered to answer any questions. Sent me for a blood test (to check my thyroid medication).
And that was it.
I guess it'll vary depending on why you have referred, but it was fairly straight forward.
I have my 16week mw appointment next week. No idea why - as I presume that'll be exactly the same as the pre appointment I had with a mw today.