I have always been able to get at least 4oz per pumping session (somethimes up to 9oz) but recently I have struggled to get 2oz. I'm worried as I am planning to leave Lily with my mum when I go out for my OH's Christmas party and need to leave her about 6 bottles of EBM. I have had what seems like a period for the past week and so was wondering if this may have affected my supply. Can anyone offer any advice? I really hope I'm not starting to produce less milk!!!