How Yeast Infections Are Diagnosed

Diagnosing yeast infections is best done by a healthcare provider. The standard test involves a physical examination—the condition can cause a clumpy white discharge. However, that discharge alone is not enough to diagnose a vaginal yeast infection. The doctor must also determine whether there is yeast present in the vaginal secretions.

Yeast infections will affect up to three-quarters of people with vaginas at some point during their lives. These common infections tend to be frustrating to deal with. They may not have serious long-term health consequences, but they're uncomfortable. They can also lead to depression and feelings of low-self worth if the discomfort is persistent, so a proper diagnosis and treatment are recommended.

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Self-Checks/At-Home Testing

Commercially available home tests for diagnosing yeast infections don't specifically test for yeast infections. Instead, they are used to determine if the vaginal pH is abnormal.

Since bacterial vaginosis (BV) is more often associated with a high vaginal pH, these tests can help point to whether the pH is more consistent with yeast or BV.

Just having yeast in the vagina isn't necessarily a problem. It's only a problem when the yeast overgrows. These tests aren't necessarily able to determine the amount of vaginal yeast and whether it is causing your symptoms.

People should not rely on commercial tests to start at-home yeast infection treatment unless similar symptoms have previously been diagnosed as yeast by a doctor. 

Lab Tests

The standard test for a yeast infection is a microscopic examination of a vaginal smear sample. Yeast is often visually detectable in such samples.

The vaginal smear can be taken by the doctor. And self-smears have been shown to be similarly effective for diagnosing yeast infections. The swab is simple and painless, and you will receive instructions on how to obtain it.

Note: This type of self-smear is different than a home test for yeast. You take the smear, but the doctor still examines it using a microscope.

Recurrent Infections

If you've had recurrent yeast infections or complicated symptoms, other tests are available. Your doctor may send your vaginal fluid to a laboratory for a yeast culture.

This can help identify the specific type of yeast that's causing an infection, which will guide the selection of appropriate treatment. Often, infections that are not curable through standard treatments are caused by less common types of yeast.

Molecular Tests

Molecular tests are sometimes used in the diagnosis of yeast infections.

As with urine tests for other STIs, these tests can identify very small amounts of yeast in the urine. This method is less useful for diagnosing a yeast infection than it is for identifying chlamydia or gonorrhea. Why? Because most people with vaginas have some yeast present in their bodies at all times, so detection of a small amount does not necessarily mean that you have a yeast infection.

Differential Diagnoses 

A number of vaginal health conditions have very similar symptoms to a yeast infection. As such, without testing, it can be difficult to tell whether someone is suffering from a yeast infection, bacterial vaginosis, trichomoniasis, or another STI.

Fortunately, whatever condition is causing the common symptoms of all these infections—itching, pain during urination, changes in vaginal discharge—is probably easily treatable if it is treated with the correct medication. That's why testing is so important. Without testing, it's hard to know if you're getting the right medication.

Frequently Asked Questions

  • How is a yeast infection diagnosed?

    A vaginal yeast infection (vaginal candidiasis) is diagnosed with a pelvic exam. Your doctors will examine the affected area and take a swab of vaginal discharge to view with a microscope. If the Candida fungus is not readily identified, a sample can be sent to the lab for further evaluation.

  • What tests can diagnose a yeast infection?

    A yeast infection can be definitively diagnosed with a culture test. This is done by introducing cells from a vaginal swab into a sterile medium to see if yeast will grow. Results are usually available within a few days.

  • How do you prepare for a yeast infection test?

    No preparation is needed. However, you should avoid douching before a pelvic exam, as this can strip away some of the infectious material and make the condition harder to diagnose. 

  • Are there home tests for yeast infections?

    Yes, there are several at-home tests that can help diagnose a yeast infection. The tests don’t detect Candida fungus; rather, they measure vaginal pH as indicated by a color change on the vaginal swab. Low acidity (high pH) is indicated by a color change and is more indicative of bacterial vaginosis. Normal acidity (indicated by a lack of color change) is more indicative of a yeast infection.

  • Can a person with a penis get a yeast infection?

    Yes, it is called a penile yeast infection (penile candidiasis) and is diagnosed with the same tests used to diagnose a vaginal yeast infection. Penile yeast infections are more common in uncircumcised people with penises and are typically recognized by a thick, white, lumpy discharge under the foreskin or within moist folds of skin.

  • What conditions look similar to a yeast infection?

    A yeast infection can sometimes be mistaken for bacterial vaginosis (BV), trichomonas vaginitis (TV), or other sexually transmitted infections (STIs). BV and TV can be differentiated by high vaginal pH (over 4.5). BV is also more likely to have a “fishy” smell, and TV often has a yellowish or green discharge; it is also more likely to bleed during a pelvic swab.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Elizabeth Boskey, PhD
Elizabeth Boskey, PhD, MPH, CHES, is a social worker, adjunct lecturer, and expert writer in the field of sexually transmitted diseases.