ANTI CHLAMYDIA ANTIBODY IGG

This test detects IgG antibodies to Chlamydia, most often Chlamydia trachomatis (genital strain) and sometimes Chlamydia pneumoniae (respiratory strain). IgG antibodies develop 2–4 weeks after infection and persist for years — sometimes lifelong — so a positive IgG indicates current or past exposure, not necessarily active infection.

For diagnosing acute genital chlamydia infection, a nucleic-acid amplification test (NAAT) on urine or a urethral / cervical swab is the gold standard — antibody testing is not suitable for screening or treatment decisions in symptomatic STI. Chlamydia IgG is most useful as evidence of past infection in infertility evaluation and in epidemiological studies.

Chlamydia is the world's most common bacterial STI. In women, untreated infection can cause pelvic inflammatory disease (PID), tubal scarring, ectopic pregnancy, and infertility. In India, where many infections are silent and access to STI screening is uneven, tubal-factor infertility from past chlamydia is a recognised major cause of secondary infertility in women.

In an infertility workup, Chlamydia IgG positivity raises the index of suspicion for tubal damage and supports earlier hysterosalpingography (HSG) or laparoscopy. It is also used to support clinical suspicion of reactive arthritis (Reiter syndrome) after a recent chlamydia infection, and as a marker of past pelvic infection where current testing is negative.

No fasting required. The test can be done at any time of day. Inform the lab if you have recently had any treatment for chlamydia, as antibodies can take weeks to develop after recent infection and may persist for years after treatment.