my ds right now does 4oz of formula.. hes 11weeks today. He was 5weeks early.. and was in the NICU not for vitals he was perfect.. it was that he was slow on eating. he had problems with sucking.. Now hes a champ. There are times he wants more and times when he has little. but he at least gets 4oz every 3hours.
even at 3 weeks, my DS could eat 6 oz! He ate about every 2-3 hours. It was all part of his growth spurt, I think. B/c after about 4 weeks, he went back to 4 oz. He also spread out his eating to every 3-4 hours. Around 3 weeks, it seemed hewas never satisfied. If you are bfing, just go with what works. People were telling me I might be overfeeding him, but he was not spitting up and didn't seem satisfied otherwise. I just followed his cues and gave him what he wanted.
DD is 3 weeks 3 days and yesterday she started taking 3oz at each feeding and then 4oz once right before we put her down. I'm starting to transition towards EBF so I'm hoping that my low supply will increase and I won't have to suppliment any more. Also, DD was 6lbs 11oz when born. At her last weigh in, at 17 days old, she was 7lbs 3oz, though I can tell she's gained a lot more weight now. How much they take depends upon their weight. DD is definitately on the small side.
Re: how much milk or formula....