Sexually Transmitted Infection (STI) Tests
Reviewed
STI tests detect infections passed through sexual contact, including chlamydia, gonorrhea, herpes, HIV, and HPV. Testing can identify infections even without symptoms, allowing treatment and preventing spread.
Preparation and collection
No special preparation for a blood test. Women may need to avoid douches and vaginal creams for 24 hours before a urine or swab test. You may need to empty your bladder before a lumbar puncture. Your provider will give specific instructions.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- STI tests may not detect infections during the window period (time between exposure and when the test can find the infection).
- False-positive and false-negative results are possible; your provider may recommend confirmatory testing.
- Not all STIs are included in a single test; you may need multiple tests based on your risk factors.
- At-home test results should be discussed with a provider for confirmation and treatment.
What to do next
If your result is positive, take all prescribed medicine as directed and notify your sexual partners. If negative but you have symptoms or ongoing risk, talk to your provider about repeat testing. Continue using condoms and consider vaccination for HPV and hepatitis B.
Evidence source
U.S. National Library of Medicine: Sexually Transmitted Infection (STI) Tests