Infection Detection

by Christine Haran

When most women experience genital itching or discharge, they tend to assume they have a yeast infection. Their next step is often quietly buying an over-the-counter product that has been advertised on TV. But genital itching can be a symptom of many other conditions, from other kinds of vaginal infections to sexually transmitted diseases to skin allergies. So unless you are fairly certain you have a bona fide yeast infection, you might want to delay treatment and not waste your money.

"Multiple studies show that symptoms such as itching are not predictive of what kind of condition you have, so a woman can easily have the wrong diagnosis, and there can be repercussions if she treats for the wrong condition," says Linda Eckert, MD, an associate professor in the department of obstetrics and gynecology at the University of Washington in Seattle.

If itching is due to a vaginal infection, it is most likely a case of bacterial vaginosis, a yeast infection or trichomoniasis. Health care providers, such as gynecologists and midwives, say that the best way to distinguish between these infections is not by looking at symptoms, but by testing the vaginal fluid.

Bacterial Vaginosis

The most common vaginal infection is bacterial vaginosis, which occurs when the balance of the microorganisms that normally live in the vagina is thrown off. BV appears to be related to sexual activity, though doctors aren't sure how. Douching also raises risk.

In BV, there is an overgrowth of certain bacteria, such as Gardnerella vaginalis, that leads to low numbers of a protective bacteria called lactobacilli, causing grayish-white vaginal discharge, itching and a fishy odor. When a gynecologist examines the vaginal fluid under a microscope, he or she will be able to see cells coated with BV bacteria. The doctor will also measure the pH of the vagina, which reflects its acidity. In BV, the vaginal pH is higher than normal. Finally, the health care provider should perform a whiff test, where drops of an alkalinizing fluid are added to the vaginal fluid, to see if it produces a fishy odor.

BV is treated with antibiotics. Untreated BV is associated with pelvic inflammatory disease, a condition that can lead to infertility, tubal pregnancy or premature delivery.

Yeast Infections

Yeast infections, the second-most common type of infections, are also due to a change in the vaginal "ecosystem." In a yeast infection, an overgrowth of yeast, usually one called Candida albicans, leads to itching or burning and sometime causes a thick, whitish discharge. Yeast infections are known to occur following a course of antibiotics or the use of oral contraceptives. They are also common in pregnant women, women with diabetes and women who wear underwear or clothes that are tight or made of fabric that does not breathe well, and in women who use feminine hygiene sprays or douches.

"There is a tremendous market for feminine hygiene sprays and douches," says David Soper, MD, a spokesperson for the American College of Ostetricians and Gynecologists vice chair of the department of obstetrics and gynecology at the Medical University of South Carolina in Charleston. "But women are better off not douching or using sprays and instead using mild soaps that don't have detergents."

Health care professionals can identify yeast infections with a physical exam and by examining vaginal fluid under the microscope; they may also choose to send a specimen out for a vaginal yeast culture to confirm an uncertain diagnosis.

Yeast infections are treated with anti-fungal medications, which are available as creams and suppositories, or as a pill called Diflucan. Women with recurrent infections may find relief from a prescription for boric acid that is prepared as a capsule that is inserted into the vagina. Boric acid changes the vaginal pH, inhibiting the growth of yeast.

According to Dr. Soper, women who have had a yeast infection before and who are not at risk for a sexually transmitted disease, can try over-the-counter products if they have the same symptoms. He warns that women should see a health care provider if symptoms don't clear up in a few days, however.


The third most common vaginal infection is trichomoniasis, or "trich," which is a sexually transmitted disease (STD) caused by a parasite that is identified by examining vaginal secretions under the microscope. While trichomoniasis does not always cause symptoms, it can cause itching and irritation as well as a yellow-green, foul-smelling discharge in women. Both partners should be treated with a single dose of a drug called metronidazole, which usually clears the infections if the partners avoid sex over the course of treatment.

Other STDs

Trichomoniasis is not the only STD responsible for vaginal symptoms. Other common STDs that may produce an irritating itch and/or a discharge include gonorrhea, chlamydia and herpes.

So before people jump to the conclusion that their itching is due to a routine yeast infection, Dr. Soper says, "people need to be honest with themselves about their risk for STDs. They have to ask: 'Do I have multiple sexual partners?' or 'Does my partner have multiple partners?'"

If someone has had unprotected sex, has a new sexual partner, or has had two or more partners in the last two months, they should be tested for an STD. Although not all women will have symptoms with gonorrhea and chlamydia, those who do often experience itching, burning during urination and a yellow discharge. Chlamydia is detected by examining a sample from the cervix, or the urine, for the Chlamydia bacteria. Similarly, the gonorrhea bacteria is detected by analyzing a fluid sample.

Both of these STDs are treated with antibiotics. It is critical to treat gonorrhea and chlamydia as they are easily passed along through unprotected sex, and can lead to complications such as pelvic inflammatory disease and infertility.

Unlike gonorrhea and chlamydia, herpes is a recurrent infection caused by a virus rather than bacteria. During "outbreaks," the virus travels from the nerves cells where it lives to the skin, causing itching and blisters in the genial area. Herpes is treated with antiviral medication given during outbreaks or on everyday basis to suppress the virus and prevent outbreaks.

Sensitive Situations

Not everyone who has itching in the genital area has an infection, however. For many women, the problem is itching of the vulva, which is the exterior portion of women's genital organs.

According to Karl R. Beutner, MD, PhD, an associate clinical professor of dermatology, University of California, San Francisco, two common skin conditions that cause vulvar itching are irritant dermatitis and contact dermatitis. While irritant dermatitis occurs when the skin is irritated by a chemical in products such as harsh soaps or detergents, contact dermatitis is an allergic, immune-system reaction to a substance. Fragrances and preservatives, for example, can cause both irritant and allergic reactions.

For people with sensitive skin in the vulvar area, Dr. Beutner recommends avoiding substances with fragrances and using mild cleansers for underwear and for skin -- and rinsing the skin or clothes thoroughly. To soothe the skin, women can use a wet, warm washcloth or take a sitz bath. Some may benefit from topical anti-inflammatory drugs such as hydrocortisone, a type of steroid. In severe causes, oral steroids are required.

Women who have the skin conditions psoriasis and eczema can have problems in the genital area. Psoriasis, an immune condition, can cause red, scaly rashes on the vulva, though this site is rarely talked about. Likewise, the dry skin condition eczema can cause itchy rashes on the vulva, which can get worse in the dry, winter air. Both conditions may be treated with topical or oral steroids that ease inflammation and itching.

Due to the popularity of shaving the genital area, folliculitis, a bacterial infection of the hair follicle that leads to itchy bumps, is not uncommon in the vaginal area today, especially among women under age 25. Folliculitis is treated with topical or oral antibiotics.

Nothing but Normal

Of course, some itching and discharge is just a normal part of the hormonal cycle, though even this kind of itching can be soothed by hydrocortisone creams or wet soaks if women find it irritating.

"Some itching and discharge that comes and goes is normal," Dr. Soper says. "If it persists, people are better off going to their doctor even if it is only to be reassured that everything is normal."

According to Dr. Beutner, women should overcome their hesitation about visiting a doctor about genital itching so they can get needed symptom relief.

"A main reason to have itching evaluated is that we're better off treating things when we know what they are than when we are guessing," he says.

Christine Haran has been a health journalist for more than seven years, and her work has appeared in Woman's Day, MAMM Magazine, Bride's Magazine, Publishers Weekly and other publications. In 2003, she received an Excellence in Women's Health Research Journalism Award from the Society for Women's Health Research. Haran has a master's degree in journalism from New York University and a bachelor's degree in english from Skidmore College.

Copyright © Christine Haran. Permission to republish granted to, LLC.