From the Guidelines
It is recommended to abstain from ejaculation for at least 48 hours before undergoing a PSA test, as this period allows for more reliable results, according to the NCCN clinical practice guidelines in oncology: prostate cancer early detection 1. When considering PSA testing, it's essential to understand the factors that can influence the accuracy of the results.
- Ejaculation can temporarily increase PSA levels in the bloodstream, which may lead to falsely elevated results.
- The NCCN guidelines suggest that results are more reliable if the patient has abstained from ejaculation for 48 hours 1.
- If the patient has not met this condition, the guidelines recommend repeating the test after 48 hours of abstention, especially if the original sample was marginally elevated 1. Some medications, such as finasteride and dutasteride, can also affect PSA levels, and their use should be considered when interpreting test results 1.
- In patients using these medications, a substantial decrease in PSA levels (approximately 50%) is expected, and failure to achieve this decrease or an increase in PSA levels while on medication may be associated with an increased risk for prostate cancer 1. It's crucial to follow the specific instructions provided by your healthcare provider, as they may have different recommendations based on your individual health situation or the purpose of your PSA testing.
From the Research
Ejaculation and PSA Testing
- There is no significant effect of ejaculation on prostate-specific antigen (PSA) levels, as shown in studies 2, 3.
- A study published in 1998 found that ejaculation had no clinically significant effect on PSA levels in a prostate cancer-screening population 2.
- Another study from 1995 found that ejaculation did not affect serum PSA concentrations in normal men 3.
- Men should not be asked to abstain from sexual activities before a PSA-screening test, as ejaculation does not have a significant impact on PSA levels 2.
Time Frame for PSA Testing After Ejaculation
- One study found that after 12 hours, serum PSA returns to baseline levels after ejaculation 2.
- It is recommended that men do not need to abstain from ejaculation before PSA testing, as the effect of ejaculation on PSA levels is not significant 2, 3.
- However, it is essential to note that other factors, such as prostatic manipulations, can affect PSA levels, and the timing of PSA testing should be considered in relation to these factors 4, 5, 6.
Other Factors Affecting PSA Levels
- Prostatic manipulations, such as digital rectal examination, prostatic massage, and transrectal ultrasonography, can affect PSA levels 4, 5, 6.
- Transrectal needle biopsy and transurethral resection of the prostate can cause significant increases in serum PSA levels, which may take up to 14 days to return to normal 5, 6.
- The timing of PSA testing should be considered in relation to these factors to ensure accurate results 4, 5, 6.