I'm not sure what's causing her throwing up when you nurse her. I only breast fed my daughter (she never once had formula) and she was a huge spitter upper. Something to remember though, is that when a baby spits up, it always looks like more than it actually is b/c it gets mixed with a lot of saliva. My daughter spat up after almost every feed for the first 6 or 7 months, but still gained weight rapidly. So the doctor said not to be concerned about it. I often wondered if it was something in my diet that cauesd it, but I never found anything particular. I did discover however, that any time I had anything chocolate, it gave her wicked diaper rash. Good luck and I hope you're able to continue nursing your daughter, it really is best for baby.
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