I have my dating scan on Thursday and was told I would receive an info pack from the hospital but nothing has arrived yet. I called up the hospital and I was just told I needed to take my notes but I have read on other posts that you usually have to drink lots beforehand. How much do I need to drink? I'm already anxious about the scan and don't want to risk messing it up. I'm going to the Rosie Maternity Hospital if anyone else has been there. Thanks!