Re: 9 week old suddenly nursing less?
How's his diaper output? As long as he is producing sufficient wet diapers, he's getting enough to eat. Poop frequency is not a great milk intake indicator at this point because many babies will significantly decrease their pooping frequency at this point, going as seldom as once a week. But if you're still seeing 1 or more poops per day, that would also be a good indicator of milk intake being just fine.
I know it can freak you out when a baby changes up his nursing pattern, but as time goes on you should expect greater efficiency at the breast, with feedings taking as little as 5 minutes. The fussing at the breast may be related to flow speed, or to being done, or just to being a baby... I wouldn't worry about it as long as diaper output is okay.
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