I don't like the term 'sex change' operation.

I think that we should call it gender based anatomy reassignment and gender based chemical alterations.

This way it is less confusing. Sex change implies that a man becomes a woman. While he may look like a woman, and act like a woman he isn't a woman. For that you would have to do the impossible 'Gender based Genetics Alteration'. As long as that y chromosome is there, you can't call him a her.

Though, a lesbian who undergoes a Gender Based Anatomy Reassignment is still a lesbian because she likes women.