About chlamydia

Chlamydia is a bacterial infection. It's one of the most common sexually transmitted infections.

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What is it?

Chlamydia is one of the most common sexually transmitted infections (STI) in the United States. It is caused by a bacteria called chlamydia trachomatis. It affects both men and women and is particularly prevalent among sexually active people under the age of 25.

Most people don’t have symptoms, so getting tested is the only way to know if you have chlamydia. It is usually easy to treat and cure with antibiotics.

If you are under 25 and sexually active, it is recommended that you have a chlamydia test once a year, and when you have sex with new or casual partners.

How is it spread?

The infection is typically spread through unprotected (without a condom) vaginal, oral, or anal sex. It can also be passed on through contact with an infected partner's genitals, even without ejaculation or orgasm. It can also be spread through the sharing of sex toys, particularly if not washed before each person uses them or if not covered with a condom.

In rare cases, transmission can occur through infected semen or vaginal fluid from someone with chlamydia coming into contact with the eye.

Additionally, pregnant mothers can pass the infection to their babies.

Chlamydia is not spread through casual contact such as kissing, hugging, holding hands, sharing baths or towels, swimming pools, toilet seats or sharing crockery and cutlery. You cannot get it from masturbating by yourself.

Symptoms

Most people with chlamydia (up to 80% of infected women and 50% of infected men) don’t have any noticeable symptoms. Any symptoms usually start a few weeks after you get chlamydia but sometimes don’t show up until months later. Sometimes symptoms disappear after a few days, but this does not mean the chlamydia has gone. Even if you don’t have symptoms, you can pass chlamydia on, and it may cause you long-term problems if it’s not treated. 

In women
For women, symptoms of chlamydia include:

  • Vaginal discharge that is unusual for you; it’s often yellowish and may have a strong smell.
  • Pain when urinating.
  • Pelvic pain or pain during sex.
  • Vaginal bleeding in between periods or after sex.
  • Pain in the lower abdomen.

In men
For men, symptoms of chlamydia include:

  • Discharge from the penis tip; it’s often white or cloudy and may be watery.
  • Pain or burning when urinating.
  • Discomfort at the tip of or down the shaft of the penis.
  • Testicular swelling or pain.

Chlamydia in other parts of the body:

Chlamydia in the rectum usually has no symptoms. You may notice pain or discomfort, discharge, or bleeding from the anus.

Chlamydia in the throat usually has no symptoms. You may notice redness or soreness in your throat or mouth. 

Chlamydia in the eye may cause pain, redness, or discharge.

How does it affect you?

While early treatment can prevent serious problems, untreated chlamydia can lead to serious health complications. If left untreated, the infection can spread from the genitals and urethra (urinary tube) to other parts of the body, resulting in potentially severe long-term health issues.

In women, chlamydia can cause a condition known as pelvic inflammatory disease (PID). If PID is not promptly treated and cured, it can cause pain, increase the risk of ectopic pregnancy (pregnancy outside the womb), and eventually lead to infertility.

In men, chlamydia can spread to the testicles, causing pain, and swelling known as epididymo-orchitis. While this is rare, there is a possibility that it could affect fertility. 

In some cases, chlamydia can cause chronic pain and arthritis (joint pain and swelling), although this is uncommon.
For pregnant individuals, untreated chlamydia can cause complications during pregnancy and can be transmitted to the baby. However, the infection can be safely treated to protect both the mother and the baby.

A positive rectal chlamydia test, particularly amongst gay or bisexual men, can sometimes be an indication that you are infected with a different and more aggressive strain of chlamydia called Lymphogranuloma veneruem – LGV. Individuals testing positive for rectal chlamydia will need to go to a clinic for LGV testing and treatment accordingly.

Diagnosis

The only way to find out if you have Chlamydia is to get tested. 

For women, Chlamydia is diagnosed by testing a vaginal swab sample.

For men, Chlamydia is diagnosed by testing a urine sample.

Diagnosis for Chlamydia in the throat and anus is made from a throat and anal swab (don’t worry, we’ll send two separate swabs).

When should I take a test?

It’s a good idea to get tested if you or a sexual partner: 

  • Have sex without a condom with a new partner.
  • Have any symptoms.
  • Have another STI.
  • Want to stop using condoms with a partner.
  • A sexual partner informs you that they have, or have recently had, chlamydia.

If you are aged under 25 and sexually active: 

  • Women – and everyone with a womb or ovaries – are advised to do a chlamydia test once a year, and after having sex with new or casual partners. 
  • Men – or anyone without a womb or ovaries – are advised to do a chlamydia test once a year if not using condoms with new or casual partners.

It's possible to be tested within a few days of having sex especially if you have symptoms, but if you have no symptoms and just want a sexual health check-up, you may want to wait up to two weeks after the last sexual contact before getting a test. This is because it can take up to 2 weeks before Chlamydia shows up on a test. This is called the window period.

Testing too early after a sexual risk, during this window period, may give you false reassurance (i.e., your test result may be negative when you are actually infected).
If you test negative for chlamydia during the window period, you may be advised to test again later, in case the first test didn’t detect it. 

You can order a home test kit for chlamydia for free. You collect samples at home that we will test in our laboratory to provide you with results.

Order a test

See our frequently asked questions for information on when you will get your test results. Frequently asked questions

Treatment

Chlamydia is easy to treat and cure with antibiotics. 

In some instances, if an individual has symptoms such as testicular pain in men or pelvic pain in women, a longer course of antibiotics may be warranted.

These treatments are prescribed and are readily available at healthcare clinics and pharmacies. Treatment is straightforward and has a success rate of 95% or more. It’s important to treat chlamydia early so it’s less likely to cause any health problems. 

If you develop symptoms or have chlamydia in the throat or rectum, you may require some further testing.

If you have no symptoms, the chlamydia should be cured when you finish your treatment.
If you had any symptoms, they should improve in a few days and be gone after 2–4 weeks. 

If you take your treatment as advised, you don’t usually need a test to check the chlamydia is cured, unless symptoms don’t go away after a few weeks, you get new symptoms or you are pregnant. 

If you are aged under 25, it’s a good idea to have another test 3-6 months after finishing treatment because you are more likely to get chlamydia again. 

Don’t have sex with anyone until you have finished treatment.

Contacting partners

If you are diagnosed with chlamydia, you should inform anyone you have had sex with within the last six months as they may also be infected. They should be advised to conduct a chlamydia test or visit a sexual health clinic.

After treatment

You should not have oral, anal, or vaginal sex during your course of chlamydia treatment or for seven days after the first dose of treatment. You should also wait until your current partner completes any treatment and until both you and your partner’s symptoms have abated. This is to avoid being re-infected and requiring further treatment.

If you have been infected with chlamydia it is possible you may also have another STI. Therefore, it is advisable that you have a full sexual health screen for gonorrhea, syphilis, and HIV. To protect yourself use condoms and encourage your partner to test for STIs also.

If you are under 25 and sexually active, it's recommended that you get tested for chlamydia every year or when you change sexual partner.

People under 25 who have chlamydia should consider re-testing three months after being treated because young adults are found to be at increased risk of catching chlamydia again.

Prevention

The best ways to help protect yourself from chlamydia and other STIs are: 

  • Use condoms when you have vaginal or anal sex.
  • Use condoms or dams for oral sex.
  • Get tested for STIs when you have a new sexual partner and before you stop using condoms with a partner.
  • If you share sex toys, cover them with a new condom or wash them thoroughly before each person uses them.

 

Chlamydia: Myths vs Facts 

Not sure whether to believe what you’ve heard about chlamydia? We’re here to bust some common myths. Here are the chlamydia facts. 


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Myth

You would know if you had chlamydia.

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Fact

Most people with chlamydia don’t have any noticeable symptoms. It’s often known as the “hidden” or “silent” infection because it’s so common to have it without knowing. The only way to know if you have chlamydia is to get tested. And the same goes for sexual partners. You can’t tell whether a partner has chlamydia or any other STIs just by looking – that’s why it’s a good idea to use condoms to help protect yourself. 


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Myth

Chlamydia always causes infertility.

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Fact

It’s important to be aware that untreated chlamydia can lead to infertility. But for most people, as long as the chlamydia is cured it won’t cause infertility or any other complications. It’s important to treat chlamydia early before it has the chance to spread to other parts of the body. If chlamydia in women isn’t treated, it can cause pelvic inflammatory disease (PID) which can cause infertility. Untreated chlamydia may cause a painful infection in the testicles which could, in rare cases, affect fertility in men. 


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Myth

Chlamydia can go away on its own.

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Fact

Chlamydia needs to be treated with antibiotics to prevent any long-term problems. Without treatment, there is a chance that eventually the chlamydia might go away – but it’s likely to take a long time. And if you have chlamydia for a long time, then it’s more likely to cause serious and painful complications – and you could pass it on to other people. The best way to look after your health is to get treated and cured as early as possible. That’s why regular testing is a good idea. 


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Myth

Once you’ve had chlamydia, you can’t get it again.

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Fact

Once you have had chlamydia, you are NOT immune to it. You can easily get it again. In fact, if you and a sexual partner both have chlamydia, it can be easy to pass it backwards and forwards between you if you’re not careful. To avoid getting chlamydia again: 

  • Take your antibiotics according to the instructions. 
  • Don’t have any sex – not even with condoms – until you have finished your treatment and any symptoms have gone. 
  • Use condoms or dams to help protect yourself when you have vaginal/frontal, anal or oral sex. 

If you are aged under 25, you are at a higher risk of getting chlamydia again so have another chlamydia test 3–6 months after finishing your treatment and get tested regularly after that. 


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Myth

You can give yourself chlamydia. 

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Fact

If you have never had any sexual activity with anyone, you can’t get chlamydia. It’s not possible to give chlamydia to yourself. You can’t get chlamydia from masturbating by yourself, although it is possible to get it from masturbating with someone else, if they have chlamydia and pass it on to you.  

It is possible to get a condition called urethritis (where the tube you wee from becomes sore or painful) without having sex. This can be caused by things like masturbating a lot or from getting soap, lotion, or another irritant into the urethra (wee tube).  


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Myth

Chlamydia only affects women.

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Fact

Anyone sexually active can get chlamydia. Women are more likely to experience serious complications – such as long-term pain and infertility – if chlamydia isn’t treated, but it can cause painful and serious complications in men too. And if men have chlamydia without knowing it, they can pass it on to sexual partners. It’s everyone’s responsibility to get tested and treated so that you can protect your own health and the health of your partner(s). 


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Myth

You can’t get chlamydia if you’ve only had one sexual partner. 

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Fact

Anyone sexually active can get chlamydia and pass it on, even if you have only had sex once. Chlamydia is easily spread through sexual activity, so if a sexual partner has chlamydia, they could pass it on to you.  
You can reduce the risk of getting chlamydia by:  

  • Using condoms for vaginal/frontal and anal sex. 
  • Using condoms or dams for oral sex. 
  • Getting an STI test whenever you change partner and before you stop using condoms with a partner. 


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Myth

If your partner tests negative for chlamydia you don’t need a chlamydia test yourself. 

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Fact

When it comes to chlamydia and other STIs, it’s important not to rely on a partner’s negative test result. You could still have chlamydia even if a partner has tested negative. The only way to be sure you don’t have chlamydia is to get tested yourself. 


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Myth

Testing positive for chlamydia means your partner must have cheated on you. 

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Fact

It can be surprising and upsetting to get a positive chlamydia test, especially if you have a long-term sexual partner. If you have only had sex with one person or been in an exclusive relationship for a while but have just tested positive for chlamydia, it doesn’t necessarily mean that your partner is cheating on you. It’s possible to have chlamydia for a long time without knowing it and a chlamydia test can’t usually tell you exactly how long the chlamydia has been there. So, it’s possible that one of you may have got it from a previous partner.  


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Myth

The antibiotics used to treat chlamydia can stop contraception from working. 

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Fact

The antibiotics used to treat chlamydia are safe to use with all types of contraception, including the combined pill, patch, ring, progestogen-only pill, implant, IUS, and injection. So, if you have sex while you are on antibiotics for chlamydia, don’t worry, you will still be protected from pregnancy. However, it’s much better not to have any sex until both you and any partners have finished chlamydia treatment and the chlamydia has gone. Otherwise, you risk giving each other chlamydia again. 


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Myth

You can get chlamydia from a toilet seat. 

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Fact

The bacteria (germs) that cause chlamydia can’t live outside the body for very long, so even if body fluids from someone with chlamydia got on to a toilet seat, they would not be able to infect someone else. 


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