11week old not eating enough

[roozocheeks]

DD was breast fed for 2 weeks with very little success, I was advised to top up with formula which I did. After 2 weeks I began expressing and was managing to keep up with the majority of her feeds (still needing 1/2 ff a day). By the end of week 6 I sadly had to give up expressing as my body was not keeping up with demand and it became impossible on a practical level.
Up to about week 8/9, DD was eating between 800 and 900ml a day. Roll on to 11weeks and she is taking roughly 700ml each day.
She currently weighs 12.5lbs so I know she is ok weight wise but I'm concerned that she should be feeding more?
Please has anyone got any tips/advice?

Thanks!

First of all you are impressively on the ball and monitoring things so congrats! Been there with the expressing - I had to return to work after maternity leave and expressed so they only had my milk at nursery. Artificial milk is fine - what all livestock farmers but few others know is that for a mammal it is absolutely vital that the newborn receives their colostrum. That perfect start has sadly been denied too many babies in their first 24 hours (before the 'real' milk comes in!).
Anyway as to taking less milk baby's weight gain is the thing - speak to your Health Visitor (I grew up with one). If you were not monitoring so closely would you be at all worried?
My DS was v sleepy and not a very active feeder and they found he had a urine infection and he had tests to check his plumbing was correct (apparently it can be all to pot) and then was on low dose antibiotics for his first year - they took it that seriously as liver damage is the risk. Always check asap with young babies. Best wishes

Thanks for your msg cdwales, I managed to get a hold of my HV yesterday and she didn't seem too concerned although wants me to start bringing DD in for weekly weighings for a bit.
She did suggest that this will be why DD is up 2/3 times during the night, and won't stop until she is taking more during the day...how I long for that day!