Re: eating every hour
Eating every hour is normal as long as diaper output and weight gain are normal. And it sounds like your baby gained over a pound in the last week, which means that weight gain is actually faster than average at this point.
That being said, it sounds like there are some aspects of your nursing relationship that could be going better. First, the shield. Shields are good tools for babies who will not latch without them. But they have drawbacks, namely that they can reduce or slow down milk transfer, making feedings take longer and requiring the baby to feed more often, which can be exhausting for mom and lead her to doubt her supply. So I would love to see you working on nursing without the shield. If you could see the LC again, that would be good.
Second, your baby had a tongue tie and it's great that it was released. But tongue ties require monitoring, because they sometimes reattach. I would see the LC about the baby's tongue, too- make sure it's functioning at 100%!
Third, the pumping sounds like it could be tweaked. Ideally, you want all the baby's supplements to be breastmilk supplements; if you are pumping enough to cover all supplements, your supply is equal to the baby's needs and transitioning to exclusively nursing is going to be easier. So let's talk pumping- how often are you pumping, how much do you pump each time, what sort of pump are you using?
Fourth, supplementing. I'm not clear on how much formula you are using per day- it would be great if you could tell us how many oz of expressed milk baby is getting per day and how many oz of formula. Maybe there's some aspect of the supplemental feedings that can be tweaked. It does sound like your baby may be being overfed if she is nursing for 20 minutes and then getting 2.5 oz of milk and formula; at 4 weeks old most babies are taking 2-4 oz of milk per feeding and 2.5 oz would be a complete feeding all by itself.
Do you happen to have access to a professional baby scale, something which is accurate to the 1/10th of an oz?
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