How to tell

I've been with my girlfriend for 2 years, we are very much in love and she's a beautiful girl. However she has some hair on her upper lip. It hasn't been bothering me that much until now. However she's gonna start working this summer in a law firm and I'm afraid that she'll be exposed to gossipping because of her facial hair. So to protect her from that I wanted to tell her that it would be best if she removed the hair. However I haven't found a sensitive way to tell her that because I don't wanna hurt her feelings.

Any advice is welcome.