Most people with chlamydia have no symptoms at all. Roughly 75% of women and 50% of men who are infected never notice anything unusual, which is why chlamydia is often called a “silent” infection. When symptoms do appear, they typically show up several weeks after exposure and look different depending on the site of infection.
Symptoms in Women
The most common sign is an unusual vaginal discharge that may appear white, yellow, or gray and can have a noticeable odor. You might also experience a burning sensation when urinating or pain during sex. Bleeding between periods or spotting after intercourse are other red flags, though many women attribute these to hormonal changes and don’t connect them to an infection.
Because these symptoms overlap with yeast infections, bacterial vaginosis, and urinary tract infections, chlamydia in women is frequently misidentified or dismissed entirely. The mild nature of early symptoms is a big part of why so many cases go undetected until complications develop.
Symptoms in Men
Men are more likely than women to notice something is off, though half still remain symptom-free. The hallmark signs include a clear or cloudy discharge from the penis, burning or pain during urination, and redness, swelling, or itching at the tip of the urethra. Some men develop pain and tenderness in one or both testicles, which can signal that the infection has spread deeper into the reproductive tract.
These symptoms often appear mild enough that men delay seeking care, particularly if the discharge is light or intermittent. Even when symptoms resolve on their own, the infection itself does not. You can still transmit chlamydia and still develop complications without treatment.
Rectal and Throat Infections
Chlamydia can infect the rectum and throat through anal or oral sex. Rectal chlamydia may cause pain, discharge, or bleeding from the rectum, though it often produces no symptoms at all. Throat infections are almost always silent, rarely causing even a mild sore throat. Because these infections are easy to miss, they require site-specific testing. A standard urine test or vaginal swab won’t detect chlamydia in the throat or rectum.
How Long Before Symptoms Appear
When symptoms do develop, they typically take several weeks to show up after exposure. This delay matters for two reasons: you can unknowingly pass the infection to partners during that window, and you may not connect the symptoms to a specific sexual encounter by the time they arrive.
For testing purposes, a chlamydia test can detect the infection about one week after exposure in most cases, and waiting two weeks catches nearly all infections. Testing earlier than one week risks a false negative, so timing your test correctly is important if you’ve had a known exposure.
What Happens If It Goes Untreated
Untreated chlamydia can move beyond the initial infection site and cause serious problems, particularly in the reproductive system.
In women, the bacteria can travel upward into the uterus and fallopian tubes, causing pelvic inflammatory disease (PID). PID symptoms include lower abdominal pain, fever, foul-smelling vaginal discharge, pain or bleeding during sex, burning during urination, and bleeding between periods. The tricky part is that PID itself can also be mild or symptom-free. Even without obvious symptoms, the inflammation can scar the fallopian tubes, leading to chronic pelvic pain, ectopic pregnancy, or infertility.
In men, untreated chlamydia can cause epididymitis, an inflammation of the coiled tube at the back of the testicle. This typically shows up as pain and tenderness on one side of the scrotum, along with noticeable swelling. The inflammation can spread from the epididymis to the testicle itself and the surrounding structures. While rare, repeated or severe episodes can affect fertility.
Chlamydia in Newborns
A pregnant person with untreated chlamydia can pass the infection to their baby during vaginal delivery. In newborns, chlamydia most commonly causes conjunctivitis (pink eye), with redness, swollen eyelids, and pus discharge appearing 5 to 12 days after birth. The bacteria can also infect the lungs and airways, potentially leading to pneumonia in the first few months of life. This is one reason routine chlamydia screening is part of standard prenatal care.
Why Screening Matters More Than Symptoms
Because the majority of chlamydia infections produce no symptoms, waiting for something to feel wrong is not a reliable strategy. The CDC recommends annual screening for all sexually active women under 25, as well as for older women with risk factors like new or multiple sexual partners. Men who have sex with men are also advised to get tested at least annually. Anyone who tests positive should be retested about three months after treatment to check for reinfection, which is common.
Chlamydia is curable with a short course of antibiotics, and treatment is straightforward when the infection is caught early. The real danger lies in the months or years an undetected infection can silently cause damage before anyone knows it’s there.