July 24, 2014
Sex Before PSA
Ask the Experts

Sex Before PSA

by Berkeley Wellness  |  

Q: Should a man avoid sex before a PSA test for prostate cancer? I was told it can affect the results—or is that a myth?

A: Though studies don’t all agree, several have shown that ejaculation can falsely increase PSA levels somewhat, at least in men 50 and older (the age group most screened), thus misleadingly indicating increased cancer risk. Avoiding ejaculation for 48 hours before a prostate-specific antigen (PSA) test is thus prudent. Otherwise, you may need to have the test repeated after abstaining if the result comes out elevated, causing unnecessary worry.

PSA is a protein produced in the prostate gland and found at high concentration in semen. The PSA test detects how much is spilling into the blood— there should be very little. Elevated blood levels may be a sign of cancer, but also of an enlarged prostate or a prostate infection.

Not just sex: Some drugs used to treat an enlarged prostate can lower a PSA reading. If you are taking finasteride (Proscar or Propecia, the latter used to treat hair loss) or dutasteride (Avodart), remind your doctor before having a PSA test so this can be taken into consideration in the interpretation of the results.

The bigger question is, should you be screened with the PSA test? That remains controversial.