I have a 6 month old baby who was diagnosed in utero with an enlarged kidney. It has been closely monitored, having regular scans to see if there has been any added pressure on the kidney. Anyway, he had a scan done 4 weeks ago and it remained the same, no worse no better, but then today he had another scan and it shows that the dam of liquid has gone down 7mm in size. I am happy and shocked that this suddenly happened. My question is, he has been very ill the last 10 days with gastro and was dehydrated, do you think there is a chance that the dehydration led to a reduction i size???