20 week scan - needs a full bladder or not?

[StuckOnARollercoaster]

For the 12 week scan there was an extra leaflet with the appointment letter explaining the need for a full bladder.
No such leaflet with 20 week scan letter - is that because you no longer need a full bladder because of being further along or is it because they assume you'll know to have a full bladder based on the previous scan?
thanks

I'm in Gloucestershire and we were told to have a full bladder. Although when I went for my 12 week scan, after drinking a litre of water I was told my bladder was too full and to let half out which was near-impossible!

20 week scan on 25th Jan and think I'm going for the middle ground of a pint this time.

My letter said I didn't need one and had a pee while I was waiting then the sonographer was a bit narky with me that she couldn't see my bladder because it was empty, i told her about the letter and she said that I should always have a drink 20 minutes before any scan.

thanks Dogsmom, that's helpful to know. Having a drink 20 minutes before doesn't sound too bad, sure I'll manage that!