Susan Hoffstetter, of the Saint Louis University School of Medicine, in Missouri, analyzed the records of more than 150 new patients of the university’s Care Vulvar and Vaginal Disease Clinic, who thought they had yeast infections, but found only 26 percent actually did.

"Everything that itches isn't a yeast infection," Hoffstetter said in a statement. "Women shouldn't just run to the drugstore if they think they have a yeast infection. The optimal thing would be to be evaluated."

The symptoms -- itching and a vaginal discharge -- could also indicate an inflammation, dry skin tissues or a sexually transmitted infection. These problems require a different treatment than the anti-fungal medicine given for a yeast infection, Hoffstetter said.

Hoffstetter advises women who think they have a yeast infection is see a health professional who will do a pelvic exam to detect swelling and unhealthy discharge and may also take a swab to get a specimen to determine if yeast is the true culprit.

The findings were presented to the International Society for the Study of Vulvovaginal Disease.