Trichomoniasis Testing: Window Periods, Accuracy & Cost

Trichomoniasis (often called "trich") is a sexually transmitted infection caused by the parasite Trichomonas vaginalis. The CDC estimates it is the most prevalent non-viral STI worldwide, affecting approximately 2.6 million people in the United States, and it spreads primarily through sexual intercourse.

It is not caused by a bacterium or a virus, which is one reason it needs its own specific test rather than being covered by tests built for other STIs.

Trichomoniasis is frequently silent. CDC guidance notes that the majority of people who have it — roughly 70% to 85% — have minimal or no genital symptoms at all, and CDC's consumer guidance puts it more bluntly: only about 30% of people develop any symptoms. Men are especially likely to have no signs.

When symptoms do appear, they can include genital itching or irritation, discomfort during urination or sex, and discharge. CDC describes discharge in women as sometimes diffuse, malodorous, or yellow-green. Because the infection often produces nothing you can feel, testing is the only reliable way to know your status.

CDC lists the incubation period for Trichomonas vaginalis as 5 to 28 days. It is honest to say there is no single published universal window for trichomoniasis testing — timing is something to discuss with a clinician, especially after a known exposure. What is clear is that a test taken too soon after sex can miss a very recent infection, even with an accurate method.

The method matters as much as the timing. CDC's STI Treatment Guidelines recommend nucleic acid amplification tests (NAAT), which detect more T. vaginalis infections than wet mount microscopy. Wet mount is faster to perform in a clinic but is relatively insensitive, so a negative wet mount does not rule out trich. If you are testing soon after a possible exposure, ask whether a later retest is appropriate — window period and accuracy always need to be read together.

Untreated trichomoniasis can cause ongoing genital discomfort and irritation, and CDC notes it is associated with a higher likelihood of acquiring and transmitting other STIs. It has also been linked to some pregnancy complications, which is part of why testing during pregnancy is discussed with a clinician.

There is also a transmission angle: an untreated person can keep passing trich to partners, often without knowing it. Treating both partners is a standard part of partner management in CDC guidance, and retesting about three months after treatment is recommended for sexually active women because reinfection is common. Trichomoniasis is treatable with antibiotics, and knowing your status is what makes treatment — and partner treatment — possible.

The CDC's national estimate — approximately 2.6 million US infections among people aged 15 to 59 — comes from population-based modeling rather than case reports, which is typical for an infection this often asymptomatic.

One honest caveat: unlike chlamydia, gonorrhea, and syphilis, trichomoniasis is not a nationally notifiable condition in the same way, so city-level trich rates are not part of standard metro surveillance reporting. This page therefore stays national in scope; you will not find credible city-by-city trichomoniasis rate tables the way you would for chlamydia or gonorrhea.

Trichomoniasis testing runs through nationwide lab networks such as Labcorp and Quest, which means you can usually get a draw close to home without a clinic visit. You can order a standalone trich test or add trichomoniasis to a broader STI panel, depending on what else you want screened in the same visit.

Insurance and self-pay are the two main paths. Using insurance may involve the plan being billed; paying yourself means the charge is not run through insurance, which some people prefer for privacy. Current pricing varies by location and by whether you add trich to a panel, so the most accurate move is to check the STDcheck pricing page directly — and if a discount is running, the checkout flow is where any coupon (such as a $10-off offer) is applied.