Re: I pumped 18 oz in one sitting
It's really difficult to say if you will lose production, and if so, when. The response to pumping and intervals between pump sessions is extremely variable, and you as an individual will have a different experience from every other individual out there. That being said, long intervals between pump sessions aren't ideal and there is a good chance that you will eventually see supply decline somewhat.
Pump breaks don't have to be long to be useful. Maybe you could sneak in a quick bathroom break and hand-express some milk into a bowl? With your large supply, my guess is that you could quickly take out a few oz of milk, and milk removal plus the stimulation from expressing would signal your body to keep on producing.
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