I've read a few times that about 100-200 years ago, men were the ones who wore pink and girls were the one who wore blue. Blue was considered a girl's color. The explanation I got was that pink is related to red and red is too "strong" for girls.
I didn't read it from any official place, just what others have said. I do know that a lot of spiritual figures (i.e., Virgin Mary) would be depicted in blue.
It's interesting how things change, you know?