I came across this post because I was looking for info on getting rid of the dark spots on my upper lip. I thought I was just getting old, and had too much sun, but I started Yaz about 5 months ago. I'm starting to think that's what made it worse. It also lowered my sex drive too. So I'm going to drop it for now.
Check out this forum:
http://www.acne.org/messageboard/yaz-side-effects-t199952.html
There are quite a few mentions of Melasma and Yaz.