Yeast is the most common cause of vaginal infection. A fungus causes vaginal yeast infections, which occur inside the vagina and in the vulvar area that surrounds the vagina. Three out of four women have at least one vaginal yeast infection during their lifetimes. The symptoms of vaginal yeast infections include vaginal itching; a thick, white vaginal discharge that may look like cottage cheese; pain during sexual intercourse; redness; burning; soreness; swelling; and general vaginal irritation. Not every woman experiences all these possible symptoms of vaginal yeast infection. Many women frequently experience yeast infections, so they are familiar with their symptoms and the course of treatment recommended for them. But if this is the first time you are having such symptoms, it's important to see your doctor to get a formal diagnosis and rule out other possibilities.