If you pump at work, do you bring multiple breast shields with you and clean them when you get home? Or do you just have one set and clean them at work? Or do you rinse them off and reuse them throughout the day? We ended up buying 8 breast shields. I bring 4 to work and leave the other 4 home to be cleaned and I rotate so I don't have to clean them as often. I'm just curious what other people do.