Trichomoniasis in women often causes a frothy, yellow-green discharge with a fishy smell, plus genital itching, burning, soreness, and pain when urinating or having sex. But roughly 70% of infected people notice nothing at all CDC. Because symptoms are nonspecific and easily missed, testing — not how you feel — is the only reliable way to know.
most common curable STI
metronidazole / tinidazole
retest
| Item | Value |
|---|---|
| Estimated US infections | ~2.6 million — most common curable STI |
| Have no symptoms | ~70% |
| Cure | >90% — metronidazole / tinidazole |
| Reinfected within 3 mo | ~1 in 5 — retest |
What trichomoniasis actually is
Trichomoniasis is caused by Trichomonas vaginalis, a single-celled parasite that swims using whip-like tails and lives in the lower genital tract. It's the most common curable non-viral STI in the US, with an estimated 2.6 million infections, and it falls disproportionately on women, who account for over 80% of cases Sex Transm Dis, 2018. The parasite irritates the vaginal lining and cervix, which is what drives the discharge, itching, and inflammation that bring most women in.
The common symptoms, explained
When trichomoniasis does cause symptoms in women, they come from the parasite inflaming the vaginal walls and cervix. The classic combination clinicians look for:
- Abnormal discharge — clear, white, yellowish, or greenish, classically frothy or bubbly and carrying a fishy odor. The frothiness and color are what distinguish it from ordinary discharge.
- Itching, burning, redness, or soreness of the vulva and vaginal opening, because the inflamed tissue becomes tender and irritated.
- Discomfort or burning when you urinate, since urine passes over the inflamed area — this can feel like a urinary tract infection.
- Pain or discomfort during sex (dyspareunia), as friction aggravates the already-inflamed lining.
- A feeling of general vaginal irritation that may worsen around your period.
Symptoms can flare and fade, which fools many women into thinking the problem cleared on its own. It didn't — without treatment the parasite stays put and stays contagious.
Signs specific to women: 'strawberry cervix' and more
During a pelvic exam, a clinician may see a finding that's almost unique to this infection: a strawberry cervix — tiny red, dotted spots on the cervix caused by pinpoint bleeding from the inflammation. It's not present in every case, but when it shows up it's a strong clue. The vaginal walls may also look red and irritated, and the discharge pooling at the back of the vagina often has the telltale frothy quality. Women experience trichomoniasis more often and more noticeably than men, who are commonly asymptomatic and can carry and pass it without ever knowing.
What about throat or rectal symptoms?
Unlike gonorrhea and chlamydia, Trichomonas vaginalis infects the genital and urinary tract — the vagina, cervix, and urethra in women. It's not a recognized cause of throat or rectal infection, so there's no oral or anal symptom set to watch for here. If you have throat or rectal symptoms after a possible exposure, those point toward other STIs and deserve their own testing.
How soon do symptoms appear?
When symptoms occur, they typically show up 5 to 28 days after infection — but they can appear much later, or never. That wide window matters: a negative feeling of being fine soon after sex doesn't mean you're clear, and symptoms that surface months later can still be from an earlier exposure. If you're trying to time a test around a specific encounter, see our guide on when to test after exposure.
What trichomoniasis gets mistaken for
This is where women most often get the wrong treatment. The fishy odor and discharge overlap heavily with bacterial vaginosis; the itching and irritation mimic a yeast infection; and the burning with urination feels exactly like a UTI. None of those over-the-counter or home remedies will cure trichomoniasis, because it's a parasite, not a yeast or the usual UTI bacteria. The differences a clinician weighs:
| Condition | Typical discharge | Odor | Key distinguishing clue |
|---|---|---|---|
| Trichomoniasis | Frothy, yellow-green | Fishy | Strawberry cervix; itching plus burning urination |
| Bacterial vaginosis | Thin, gray-white | Fishy | Usually little itching or soreness |
| Yeast infection | Thick, white, clumpy | None or mild | Intense itching, no fishy smell |
| UTI | None | None | Frequency/urgency, no vaginal discharge |
Because the overlap is so close, guessing is risky. A simple test sorts it out quickly and prevents weeks of treating the wrong thing.
Complications and when it's urgent
Trichomoniasis is curable, but leaving it untreated isn't harmless. The inflammation it causes makes the genital tissue more vulnerable, which increases the risk of getting or spreading other STIs, including HIV CDC STI Treatment Guidelines, 2021. In pregnancy, the stakes rise: untreated infection raises the chance of preterm birth (delivery too early) and low birth weight, both of which can affect a newborn's health. If you're pregnant or might be, read trichomoniasis in pregnancy for what's safe and recommended.
There's no single dramatic emergency presentation for trich, but get prompt care for high fever, severe pelvic or lower-abdominal pain, or pregnancy with these symptoms — those warrant being seen quickly rather than waiting on a routine appointment.
Who should get screened
Because most infections are silent, testing is driven by risk, not just symptoms. Routine annual screening is recommended for women living with HIV, even without symptoms. Beyond that, get tested if you have any of the symptoms above, a new or multiple partners, a partner who's been diagnosed, or another STI on board. Remember that men are usually symptom-free, so a partner can pass it to you without either of you suspecting it.
A practical, honest note: a diagnosis here is common and treatable — clinics handle it every single day, and it says nothing about you as a person. Don't let embarrassment keep you from getting answers. If you're due, you can get tested without a referral at most clinics.
How it's confirmed
Diagnosis is straightforward: most cases are caught from a urine cup, a self-collected vaginal swab, or a quick exam, with results usually back in a few days, and it's free or low-cost at health departments, Planned Parenthood, and Title X clinics. For the full breakdown of test types and accuracy, see trichomoniasis testing & diagnosis.
Treatment, in one line
Trichomoniasis is cured with prescription antiparasitic pills, and for women a multi-day metronidazole course is now preferred over the older single large dose — in a randomized trial about 19% of women given the single dose were still infected at follow-up versus 11% on the multi-day course Muzny et al.. Your partner needs treatment too, or you'll pass it back and forth. Full details are on trichomoniasis treatment.
When to see a clinician
See a clinician if you have new or unusual discharge, a fishy odor, genital itching or soreness, burning with urination, or pain during sex — especially if home or over-the-counter treatments aren't working, which is a strong hint the cause isn't yeast. Also get checked if a partner was diagnosed, you've had a new partner, or you're pregnant. Don't treat blindly; a quick test points you to the right cure.