Today was my first day back at work and I'm pumping. I'm also able to go visit my daughter at lunch to nurse. Another mother at work told me that even though I am pumping, my milk supply will diminish some because I'm not with my daughter. Are there any suggestions to keep up my milk supply while working?
Well, that wasn't very helpful of her!
Many mothers are able to go back to work, pump, and make it to a year or longer. It's true that you may see a bit of a drop, but it likely won't be significant. PPs have already given you some good advice. One thing I'll add is that you may see that by the end of a work week, you aren't pumping as much as you did earlier in the week. But after a weekend of exclusive nursing, you'll often pump more milk on Monday.
One thing that worked for me was to nurse DS when I dropped him off with the sitter, so that we got one more nursing session in.