Chlamydia is far more common in women than in men. The risk is highest among adolescents and young adults (generally up to age 25), who are more likely to take risks with their sexual behavior.

Chlamydia cannot be seen, so you cannot tell if someone has it. Since most people are unaware they are infected, chlamydia can get transmitted from person to person without your knowledge.

Other factors that may increase the chances of chlamydia:

Multiple or frequent changes in sex partners
Inconsistent or incorrect condom use —latex condom use helps prevent the spread of sexually transmitted infections (STIs)
A history of chlamydia or other STIs—reinfection is common and can lead to serious reproductive complications
Excessive alcohol or illegal drug use—increases the risk of risky sexual behavior
Men having sex with men

Another risk factor for women is cervical ectropion, a condition where cells from inside the cervix are on the outside. Although it usually does not cause problems, it can make you more susceptible to infection.

References

2015 Sexually transmitted diseases treatment guidelines. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/std/tg2015/default.htm. Accessed January 29, 2021.

Chlamydia—CDC fact sheet (detailed). Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/std/chlamydia/STDFact-chlamydia-detailed.htm. Accessed January 29, 2021.

Chlamydia genital infection. EBSCO DynaMed website. Available at: https://www.dyname... . Accessed January 29, 2021.

Mishori R, McClaskey EL, WinklerPrins VJ. Chlamydia trachomatis infections: Screening, diagnosis, and management. Am Fam Physician. 2012;86(12):1127-1132.

Last reviewed March 2020 by EBSCO Medical Review Board David L. Horn, MD, FACP
Last Updated: 1/29/2021

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