Genital pain can come from several sexually transmitted infections — most commonly genital herpes (painful blisters and sores), and less often chlamydia, gonorrhea, or trichomoniasis, which usually cause burning with urination, discharge, or soreness rather than open sores. But pain isn't always an STI, and the only way to know which one you have is a test.
painful blisters that crust over; tends to recur
often silent; discharge or burning if anything
discharge and burning; can also hit throat/rectum
frothy, itchy discharge with an odor
| Item | Value |
|---|---|
| Genital herpes | managed — painful blisters that crust over; tends to recur |
| Chlamydia | curable — often silent; discharge or burning if anything |
| Gonorrhea | curable — discharge and burning; can also hit throat/rectum |
| Trichomoniasis | curable — frothy, itchy discharge with an odor |
The short list of likely causes
When something hurts down there, the usual STI suspects are genital herpes, chlamydia, gonorrhea, and trichomoniasis. Herpes is the one that causes sharp pain from sores, while the others more often cause a burning, raw, or aching feeling tied to urination, discharge, or sex. Several of these infections are frequently silent, so plenty of people who have them feel nothing at all. Pain is a clue, not a diagnosis.
Which STIs cause genital pain
Genital herpes
Genital herpes is the classic painful STI. It's caused by two viruses, herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) CDC. The tell-tale pattern is small blisters that break open into painful, raw sores on or around the genitals, rectum, or mouth. A first outbreak tends to be the worst, with sores that can take a week or more to heal and flu-like symptoms such as fever, body aches, and swollen glands as your body mounts its first response. Repeat outbreaks are usually shorter and milder, and some people get a warning prodrome — tingling, itching, or a burning ache — a day or so before sores appear.
Most people who carry the virus have no or very mild symptoms and never know it, and the majority of HSV-2 infections go undiagnosed. So no sores doesn't mean no herpes. If you do have active lesions, that's the best time to confirm it, and once it's confirmed you have options for managing outbreaks and lowering transmission, including standard antivirals and a range of alternative herpes treatments.
Chlamydia
Chlamydia is caused by the bacterium Chlamydia trachomatis CDC. It's a famously silent infection — roughly three quarters of infected women and half of infected men have no symptoms at all. When symptoms do show up, they usually appear within one to three weeks after exposure. In women that can mean abnormal vaginal discharge and burning on urination; if the infection climbs higher into the reproductive tract, it can cause lower-abdominal or low-back pain, pain during intercourse, bleeding between periods, and fever. That deeper, aching pelvic pain is a warning sign that it may be spreading, which is when chlamydia gets dangerous for fertility.
Because it's so often silent and easy to catch again from an untreated partner, retesting after treatment matters — see what to know about chlamydia reinfection.
Gonorrhea
Gonorrhea comes from the bacterium Neisseria gonorrhoeae and can infect the genitals, rectum, and throat CDC. In men, the usual complaints are burning when urinating and a white, yellow, or green penile discharge; less commonly, the testicles become swollen and painful, which signals the infection has spread to the epididymis (the tube behind the testicle that stores sperm) and can threaten fertility. Most women have no symptoms, but when they do it's painful or burning urination, increased vaginal discharge, and bleeding between periods. The burning-with-discharge picture overlaps heavily with chlamydia, which is one reason clinicians often test for both at once. You can read more about the gonorrhea test and what the results mean.
Trichomoniasis
Trichomoniasis is caused by a protozoan parasite, Trichomonas vaginalis, and it's the most common curable STI CDC. About seventy percent of infected people have no signs at all. When symptoms appear, they may show up anywhere from about five to twenty-eight days after infection, though they can also turn up much later, so timing is a poor guide. Women may notice itching, burning, redness or soreness of the genitals, discomfort urinating, and a clear, white, yellowish, or greenish discharge that often has a fishy smell. Men usually feel nothing, but some get itching or irritation inside the penis, burning after urinating or ejaculating, and discharge. To confirm it, see how trichomoniasis testing & diagnosis works.
When it's not an STI
Not every ache or sore is a sexually transmitted infection. Genital pain can also come from simple trauma — friction from sex, rough clothing, or shaving nicks — and from irritation by soaps, spermicides, or new products. Non-STI infections matter too: yeast infections and bacterial vaginosis cause itching, burning, and discharge in women, and urinary tract infections produce burning urination that can be mistaken for an STI. Skin conditions, ingrown hairs, and friction blisters round out the list. These don't need an STI panel to fix, but they overlap enough in how they feel that you can't reliably tell them apart on your own.
How to tell them apart
There are a few discriminating features worth knowing. True open, painful sores or blisters point strongly toward herpes. Burning with urination plus a colored discharge leans toward gonorrhea or chlamydia. A frothy or fishy-smelling discharge with itching suggests trichomoniasis or bacterial vaginosis. Deep pelvic or low-back pain, fever, or painful sex hints the infection has spread and needs prompt care.
These patterns overlap too much to settle by sight, and several of these infections are frequently silent. A test tells you which one, if any, it actually is. Self-diagnosis fails here because overlapping symptoms leave you guessing, and a test gives you an answer.
Side-by-side comparison
| Infection | Type of pain | Discharge | How often silent | Timing of symptoms |
|---|---|---|---|---|
| Genital herpes | Painful blisters/sores; first outbreak may have fever, body aches | None typical | Most have no/mild symptoms; majority of HSV-2 undiagnosed | Not stated on current CDC pages |
| Chlamydia | Burning urination; deeper pelvic/low-back pain if it spreads | Abnormal vaginal discharge | ~3/4 of women, ~1/2 of men have none | Usually 1–3 weeks if symptoms occur |
| Gonorrhea | Burning urination; swollen/painful testicles in men | White, yellow, or green | Most women have none | Not stated on official pages |
| Trichomoniasis | Itching, burning, soreness; burning after urination/ejaculation | Often frothy, fishy-smelling | ~70% have none | About 5–28 days, sometimes later |
How it's tested
For all of these, a NAAT (nucleic acid amplification test) is the gold-standard method, and for herpes a swab of an active sore confirms it by NAAT or culture CDC 2021. In practice that means a urine sample, a self-collected swab, or a quick exam depending on what's suspected. You can get tested at a clinic, and if your exposure was recent, check when to test after exposure so you don't test too early to be accurate.
What to do next
If you have genital pain, don't try to wait it out or guess. Stop sexual contact until you've been evaluated, and get tested for the common causes at once. Chlamydia, gonorrhea, and trichomoniasis are all curable, and herpes is very manageable. Testing is often free or low-cost at health departments, Planned Parenthood, and Title X clinics, with results usually back in a few days. Once you know what it is, treatment is straightforward, so start there rather than self-treating.
Red flags — when to get seen urgently
- You have a fever along with genital pain, which can mean an infection is spreading.
- Lower-abdominal or pelvic pain, pain during sex, or bleeding between periods — possible signs the infection has moved deeper.
- Swollen, painful testicles, which can threaten fertility if untreated.
- Sores that are spreading fast, intensely painful, or not healing, or that come with severe trouble urinating.
- You're pregnant and have any genital pain, sores, or unusual discharge.