I have it too.
The more hormones you take the worse it gets and there is no real way of getting rid of it apart from stopping the hormones...
Using spf doesn't prevent it although it helps a bit. Wearing a hat too can help.
I have tried everything, mine is in the classic spot over my nose and cheeks. Fortunately not dark or purplish but golden tan and it melts in with my freckles. I still think it's unsightly and don't like going out with bare skin. I use spf 30-50 every day so clearly that's not a solution. Also it makes my skin stay quite pale which makes the spots more visible! I find self tanner helps even it out a bit. In the winter I use a cream with 10% AHA acid but you can't use that in the summer because exfoliating can make the skin even more prone to melasma/cloasma. The AHA helps a bit.
I have read about laser but it can make it even worse! The Asian bleaching creams are cancerogenic and dangerous.
Unless you can stay out of the sun completely (and who wants to?) your best bet is to use spf 30 or higher every time you go out the door, use AHA or BHA except in the summer and get a good foundation that will cover most of it. I recommend Stila Stay all day or any foundation that is heavy coverage.
I say be happy it's not on your face.
I'd much prefer to have my brown spots on my neck and not in the middle of my face.
