Chlamydia IgG Antibody, Serum (Qualitative Immunoassay)

Why This Test Is Done

Your healthcare provider may order this test if you have symptoms of chlamydia (such as unusual discharge, pain during urination, or pelvic pain) or if you’re at higher risk for infection (e.g., sexually active individuals, those with multiple partners, or those with other sexually transmitted infections). It can also be used for screening in certain populations. This test does not diagnose active infection but can confirm past exposure.

What to Expect Before the Test

No special preparation is needed. You’ll provide a blood sample, usually drawn from a vein in your arm. The test is quick and typically done in a clinic or lab setting.

What the Test Results Mean

A positive result means your body has produced IgG antibodies against chlamydia, suggesting past exposure. A negative result means no detectable antibodies were found at the time of testing. Antibody levels may not indicate recent infection, so additional testing (such as culture or PCR) may be needed for active chlamydia diagnosis.

Common Causes of False Results

False negatives are possible if the test was done too soon after exposure or if the infection was treated before testing. False positives are rare but can occur due to cross-reactivity with other infections or laboratory errors.