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What is Chlamydia?

Chlamydia is a common Sexually Transmitted Infection (STI) most often spread during vaginal, anal, or oral sex. Most people with chlamydia DO NOT have symptoms, but it can lead to Pelvic Inflammatory Disease and infertility.

How can I prevent chlamydia?

  • Use a condom EVERY TIME you have vaginal or anal sex.
  • Use a condom or dental dam EVERY TIME you have oral sex.
  • Limit your number of sex partners.
  • Talk with your partner about their STI status and getting tested.
  • Remember: drugs or alcohol may cause you to forget to use protection if you have sex and put you at risk for an STI.

Abstinence is the only sure way to prevent STIs and pregnancy.

What is chlamydia testing?

  • Testing is quick, easy, and confidential. Testing is FREE in many locations!
  • Most chlamydia tests involve peeing in a cup (or a quick, painless swab).
  • If you test positive, most people only need one dose of antibiotics to CURE chlamydia (wait 7 days after treatment before having sex).

When should I get tested?

You should get tested for chlamydia and other STIs:

  • After you have unprotected sex, especially if you don’t know your partner’s status.
  • After you have sex with a new partner.
  • Once a year if you are a sexually active men and woman under 25.
  • Once a year if you have multiple sex partners.
  • 3 months after you are treated for an STI.
  • When you are pregnant.

Chlamydia is an invisible infection with no obvious symptoms and can easily go undetected without a test. You can even catch chlamydia more than once.

Click here to find a free and confidential testing location near you!

Click here for more information on STIs.

Boston Public Health Commission
1010 Massachusetts Ave, 6th Floor, Boston, MA 02118.
Phone:(617) 534-5395 Email: