My LO is 15 months now and I have been pumping since I returned to work when he was 4 months. I had no issues in the beginning, getting more than enough pumped milk to meet his needs- average pumped amount would be 12-14 ounces a day, he would only take 8-9 oz while away. I have a surplus of frozen milk- not TONS as we rotate through it, but plenty to meet any pumping shortcomings.
Since he was about 12 months, my pumped supply has gone way down, more "normal" I guess, in that I get about 1-3 oz per pumped session. This leaves me with about 7-8 oz average, but I have had more and more days of getting the lower end of the range, which leaves me about 4 oz, and he is still taking 8 oz while I am at work. I have changed out all of my pump parts, my pump seems to be in good working order, I even sized down on my pump flange. I am not dieting, drinking plenty of water. I just got back from being on vacation for 3 weeks where I was nursing full time and going through a growth spurt, today is my first day back at work/pumping, and my pump supply is still low. What am I missing?