The most common vaginal infections are bacterial vaginosis (BV), trichomoniasis, and vaginal yeast infection or candidiasis. Some vaginal infections are transmitted through sexual contact, but others such as yeast infections probably are not, depending on the cause.

Vaginal Yeast Infection

Vaginal yeast infection is a common cause of vaginal irritation. Doctors estimate that approximately 75 percent of all women will experience at least one symptomatic yeast infection during their lifetimes. Yeasts are always present in the vagina in small numbers, and symptoms only appear with overgrowth. Several factors are associated with increased symptomatic infections in women, including pregnancy, uncontrolled diabetes mellitus, and the use of oral contraceptives or antibiotics. Other factors that may increase the incidence of yeast infection include using douches, perfumed feminine hygiene sprays, and topical antimicrobial agents, and wearing tight, poorly ventilated clothing and underwear. Whether or not yeast can be transmitted sexually is unknown.

Symptoms

The most frequent symptoms of yeast infection in women are itching, burning, and irritation of the vagina. Painful urination and/or intercourse are common. Vaginal discharge is not always present and may be minimal. The thick, whitish-gray discharge is typically described as cottage-cheese-like in nature, although it can vary from watery to thick in consistency.

Diagnosis

Because few specific signs and symptoms are usually present, this condition cannot be diagnosed by the patient's history and physical examination. The doctor usually diagnoses yeast infection through microscopic examination of vaginal secretions for evidence of yeast forms.

Treatment

Various antifungal vaginal medications are available to treat yeast infections. Women can buy some antifungal creams, tablets, or suppositories over the counter for use in the vagina. But because BV, trichomoniasis, and yeast infection are difficult to distinguish on the basis of symptoms alone, a woman with vaginal symptoms should see her physician for an accurate diagnosis before using these products.

Bacterial Vaginosis

Bacterial vaginosis (BV) is the most common cause of vaginitis symptoms among women of childbearing age and is associated with sexual activity. BV reflects a change in the vaginal ecosystem. This imbalance, including pH changes, occurs when different types of bacteria outnumber the normal ones. A change in sexual partners and douching may increase the risk of acquiring bacterial vaginosis.

Symptoms

The primary symptom of BV is an abnormal, odorous vaginal discharge. The fish-like odor is noticeable especially after intercourse. Nearly half of the women with clinical signs of BV, however, report no symptoms. A physician may observe these signs during a physical examination and may confirm the diagnosis by doing tests of vaginal fluid.

Diagnosis

A healthcare worker can examine a sample of vaginal fluid under a microscope and can make a diagnosis based on the absence of lactobacilli, the presence of numerous "clue cells" (cells from the vaginal lining that are coated with BV organisms), a fishy odor, and decreased acidity or change in pH of vaginal fluid.

Treatment

You can be treated with antibiotics.

Trichomoniasis

Trichomoniasis, sometimes referred to as "trich," is a common STD that affects 2 to 3 million Americans yearly. Trichomoniasis is primarily an infection of the urogenital tract, and the vagina is the most common site of infection in women.

Symptoms

Trichomoniasis, like many other STDs, often occurs without any symptoms. Men almost never have symptoms. When women have symptoms, they usually appear within four to 20 days of exposure. The symptoms in women include a heavy, yellow-green or gray vaginal discharge, discomfort during intercourse, vaginal odor, and painful urination. Irritation and itching of the female genital area, and on rare occasions, lower abdominal pain also can be present.

Treatment

Because men can transmit the disease to their sex partners even when symptoms are not present, it is preferable to treat both partners to eliminate the parasite. Metronidazole is the drug used to treat people with trichomoniasis. It usually is administered in a single dose. People taking this drug should not drink alcohol because mixing the two substances occasionally can cause severe nausea and vomiting.