Personally I think it depends on how important it is to you. The longer you wait the harder it is. If it is a new relationship I think it would be much better to try and expose her to that lifestyle in some way shape or form. Mention a latest court ruling or some kind of news article and see what her response is. If she pops right out as anti-whatyouare right off the bat move on. If not, hang around a bit and decide a bit later.
If being with a partner that accepts you for what you are entirely then make sure that is considered very early in the relationship.