Just depends on what I have handy to use and what pattern I choose. If I know the gender, I may choose pink or blue, but then I like pale yellow and pastel green to make for little ones, and as someone else said, I try not to make it too babyish, so they can enjoy the quilt as they get older. I personally don't care for red or black for a baby quilt, unless these colors are scattered in with other bright colors. I think anymore unless parents are color picky, almost any color will work, especially pastel colors.