When I got my first PSA test I asked the doctor the same thing, in case sexual activity could be raising my PSA. He said that it could but, at that time, it wouldn't be enough to go from safe to danger zone. But, now that there's no prostate, I don't see how sexual activity could raise it in any way, any PSA left in your system that is detectable indicates it may be hanging out elsewhere. What's your urologist say?