My milk went blue from an infection. It started out with a light tint that gradually became a lot stronger (ummm....we're talking it actually became bright turquoise!!!). 2 weeks later my milk was gone & nothing we could do would bring it back. Turns out that if I'd gone on antibiotics that first week everything probably would have been fine. It just didn't present like normal mastitis until the day before I dried up, and at that point it was too late.
This may NOT be what's going on with you. Human milk changes in it's composition as our little guys age...and that also affects the color/consistancy.
2 things that LEAP to mind if it's not an infection are:
- Did you just start on solid foods? (That will change the comp of your milk faster then about anything)
- Is working / bottle feeding new?
Also, if you just started working, you may notice your little one staying up more at night, and waking up more to be fed. Mine would change his eating/sleeping schedule every 3 months. I was in school with classes at different times...and after about two weeks into a new quarter *poof*. He changed his schedule to get more time/meals from mum. Babies are amazingly talented in getting what they want, if you give them half an opportunity. :)