Almost anything that irritates the prostate can cause "high" PSA numbers. A bicycle seat can do that (irritate the prostate), so I guess a MC seat could do it too. The high reading is typically temporary and will fall back into a range that is normal for you following rest. Does that mean a MC seat can "cause" high PSA numbers? I'm not an MD so I can't answer that question, but it definitely does not sound like anything I would be concerned about.