Mine won't go past 4 oz no matter what and I'm wondering if this is why I'm routinely up 5-7 times per night to feed him! He also goes long stretches in the day where he refuses to eat and then is up sometimes as much as hourly at night to eat. I pump so this ain't fun!
I've tried to get him to take more and it's like he just snacks or "tops off" and then wants to eat again pretty soon. Obviously, I cannot force him to eat. But momma needs some sleep. I'm getting delirious from lack of sleep and I have a 3 year old who needs some attention too!