All of Healthily's articles undergo medical safety checks to verify that the information is medically safe. View more details in our editorial policy. It's passed on from one person to another through unprotected sex sex without a condom and is particularly common in sexually active teenagers and young adults. If you live in England, are under 25 and are sexually active, it's recommended that you get tested for chlamydia every year or when you change sexual partner.
Basic Fact Sheet Detailed Version. Basic fact sheets are presented in plain language for individuals with general questions about sexually transmitted diseases. The content here can be syndicated added to your web site. Print version pdf icon.
Chlamydia is a sexually transmitted infection. Anyone who is sexually active can get chlamydia, but the infection is more common in some groups, including young people and gay and bisexual men. If left untreated, the infection can cause complications, including infertility and reduced fertility. It can increase the likelihood of passing on or acquiring HIV. It can also be passed on by sharing sex toys if they are not washed or not covered by a new condom each time they are used.
Chlamydia is caused by Chlamydia trachomatis bacteria. It is one of the most common STIs in the world. The majority of chlamydia infections are among people 15 to 24 years old and it is more common among women than men.