Interesting question. Years ago, I'd have said absolutely. But, I think now that it totally depends on who your partner is (or will become). If your partner is a one time fling, then yes, in that you don't want to move forward with no clue of what you might be bringing with you. If your partner is someone with whom you intend to spend the rest of your life, I think not. Provided you know that you and your partner are both STI free and committed to one another, their history will come out over time. Unless that history includes something that is a threat to you, I don't think it's necessary for you to know.