Definition
Chlamydia is an infection that can be passed from one person to another through sexual contact. This type of infection is known as sexually transmitted infection (STI).
Alternative Names
Cervicitis - chlamydia; STI - chlamydia; STD - chlamydia; Sexually transmitted - chlamydia; PID - chlamydia; Pelvic inflammatory disease - chlamydia
Causes
Chlamydia is caused by the bacteria Chlamydia trachomatis. Both males and females may have this infection. However, they may not have symptoms. As a result, you may become infected or pass the infection to your partner without knowing it.
You are more likely to become infected with chlamydia if you:
- Have sex without wearing a male or female condom
- Have more than one sexual partner
- Use drugs or alcohol and then have sex
- Have been infected with chlamydia before
Symptoms
Many women do not have symptoms. But some have:
- Burning when they urinate
- Pain in the lower part of the belly, possibly with fever
- Painful intercourse
- Vaginal discharge or bleeding after intercourse
- Rectal pain
If you have symptoms of a chlamydia infection, your health care provider will collect a sample for culture or a test called nucleic acid amplification.
In the past, testing required a pelvic exam by a health care provider. Today, very accurate tests can be done on urine samples. Vaginal swabs, which a woman collects herself, can also be tested. Results take 1 to 2 days to come back. Your provider may also check you for other types of STIs. The most common STIs are:
Even if you have no symptoms, you may need a chlamydia test if you:
- Are 24 years old or younger and are sexually active (get tested every year)
- Have a new sexual partner, more than one partner or a partner with an STI
Treatment
Chlamydia can be treated with an antibiotic. Some of these are safe to take if you are pregnant. Common side effects include:
Both you and your partner need to take the antibiotics.
- Finish all of them, even if you feel better and still have some left.
- All of your sexual partners should be treated. Have them take the medicines even if they do not have symptoms. This will prevent you from passing the STIs back and forth.
You and your partner are asked to abstain from sexual intercourse during the time of treatment.
Gonorrhea often occurs with chlamydia. Therefore, treatment for gonorrhea is often given at the same time.
Safer sex practices are needed to prevent becoming infected with chlamydia or spreading it to others.
Outlook (Prognosis)
Antibiotic treatment almost always works. You and your partner should take the medicines as directed.
If chlamydia spreads into your uterus and fallopian tubes, it can cause scarring. Scarring can make it harder for you to get pregnant. You can help prevent this by:
- Finishing your antibiotics when you are treated.
- Making sure your sexual partners also take antibiotics. You may ask your provider for a prescription for your partner without your partner being seen by the provider.
- Talking to your provider about being tested for chlamydia and seeing your provider if you have symptoms.
- Wearing condoms and practicing safer sex.
When to Contact a Medical Professional
Contact your provider if:
- You have symptoms of chlamydia.
- You are worried that you might have chlamydia.
References
Centers for Disease Control and Prevention website. Sexually transmitted infections treatment guidelines, 2021. Chlamydial infections in adolescents and adults. www.cdc.gov/std/treatment-guidelines/chlamydia.htm. Updated July 22, 2021. Accessed April 22, 2024.
Centers for Disease Control and Prevention website. Getting tested for STIs. www.cdc.gov/sti/testing/. Updated April 9, 2024. Accessed July 24, 2024.
Centers for Disease Control and Prevention website. Sexually transmitted infections treatment guidelines, 2021. Chlamydial infections in adolescents and adults. www.cdc.gov/std/treatment-guidelines/chlamydia.htm. Updated July 22, 2021. Accessed April 22, 2024.
Reno HEL, Geisler WM. Diseases caused by chlamydiae. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 294.
US Preventive Services Task Force, Davidson KW, Barry MJ, et al. Screening for chlamydia and gonorrhea: US Preventive Services Task Force Recommendation Statement. JAMA. 2021;326(10):949-956. PMID: 34519796 pubmed.ncbi.nlm.nih.gov/34519796/.