Vulvovaginal Candidiasis

Vulvovaginal candidiasis is a common fungal infection affecting the vagina and vulva, causing discomfort through itching, burning, and abnormal discharge. While not life-threatening, it affects three out of four women at least once in their lifetime.

Table of contents

• What Is Vulvovaginal Candidiasis?
• Causes and Risk Factors
• Symptoms
• Diagnosis
• Classification of the Disease
• Treatment
• Prevention

What Is Vulvovaginal Candidiasis?

vaginal yeast infection, vaginal candidiasis, vaginal thrush, candidal vulvovaginitis, vulvovaginal yeast infection, vulvovaginal candidosis, monilial vulvovaginitis

• vagina
• vulva

Vulvovaginal candidiasis is a fungal infection that causes inflammation of the vulva and vagina. The condition occurs when a type of yeast called Candida (a fungus that normally lives in your body) grows too much^[1]. The most common species causing this infection is Candida albicans, though other Candida species can occasionally be responsible^[3].

This infection is not considered a sexually transmitted infection, though it can sometimes be passed through sexual contact^[1]. An estimated 75% of women will experience at least one episode of vulvovaginal candidiasis during their lifetime, and 40% to 45% will have two or more episodes^[3]. The condition is most common in women during their reproductive years, particularly after puberty and before menopause^[1].

About 10% to 20% of women carry Candida species in the vagina without any symptoms^[3]. The presence of yeast alone does not mean you have an infection. Candida is part of the normal microorganisms found in many women’s bodies^[2]. Problems only arise when this yeast grows out of control.

Causes and Risk Factors

Vulvovaginal candidiasis happens when the balance of microorganisms in your vagina gets disrupted. Normally, other bacteria help keep Candida growth under control. When this balance shifts, Candida can multiply rapidly and lead to infection^[1].

Several factors can throw off this delicate balance and increase your risk of developing a yeast infection. Taking antibiotics is one of the most common causes. Antibiotics kill bacteria that cause infections, but they also destroy the good bacteria in your vagina that help control yeast growth^[1].

Hormonal changes play a significant role in yeast infections. Anything that disrupts or changes your hormones can affect the balance of Candida in your vagina. This includes pregnancy, using birth control pills, and normal changes during your menstrual cycle^[1]. Women taking higher dose combined oral contraceptive pills or using estrogen-based hormone replacement therapy are at increased risk^[7].

Medical conditions can make you more vulnerable to yeast infections. Having unmanaged diabetes is a significant risk factor because extra sugar in your body can feed yeast in your vagina and weaken your immune system^[1]. Being immunocompromised, whether from HIV infection, underlying immunodeficiency, or taking immunosuppressive medications like corticosteroids, also increases risk^[3].

Other factors that raise your chances of getting a yeast infection include staying in wet clothes or swimsuits for extended periods, wearing tight or non-breathable clothing, and using scented tampons, sprays, soaps, or deodorants^[1]. Obesity and iron deficiency anemia have also been associated with increased risk^[7].

Symptoms

The symptoms of vulvovaginal candidiasis can range from mild to moderate and typically affect both the inside and outside of your vaginal area. The most common symptom is itching and irritation in the vagina and at the vaginal opening, called the vulva^[4].

Many women experience a burning sensation, particularly during sexual intercourse or while urinating^[3]. You may notice redness and swelling around your vulva and vagina, though redness can be harder to see on darker skin tones^[4]. Small cuts or tiny cracks in the skin of your vulva may also develop^[1].

Changes in vaginal discharge are typical with yeast infections. The discharge is usually thick and white, often described as looking like cottage cheese^[1]. Unlike some other vaginal infections, yeast infection discharge typically has little or no odor^[4].

Some women may experience vulvar edema, excoriations (scratches or abrasions), and vaginal pain and soreness^[2]. A bright red rash may affect the inner and outer parts of the vulva, sometimes spreading widely to include the pubic area, groin, and thighs^[7].

Symptoms can last just a few hours or persist for days, weeks, or rarely months. They can be aggravated by sexual intercourse^[7]. It is important to remember that these symptoms are not specific to vulvovaginal candidiasis and can occur with other vaginal conditions, so proper diagnosis by a healthcare provider is essential^[3].

Diagnosis

Your healthcare provider may suspect a yeast infection based on your symptoms, but additional testing is often needed to confirm the diagnosis^[1]. A proper diagnosis is important because many women who think they have a yeast infection actually have something else^[5].

The diagnostic process typically begins with a medical history and questions about your symptoms. Your healthcare provider will want to know about the nature, quantity, and color of any discharge, as well as details about irritation, itching, burning, and pain during sex^[5].

A pelvic examination is usually performed. During this exam, your healthcare provider will look at your outer genitals for signs of infection, then use an instrument called a speculum to examine inside your vagina and view your cervix^[14].

Laboratory testing often includes taking a sample of vaginal discharge. This sample can be examined under a microscope after mixing it with saline or a 10% potassium hydroxide (KOH) solution. The KOH preparation improves visualization of yeast by breaking down other material that might obscure the yeast or pseudohyphae (fungal structures)^[3]. If budding yeasts, hyphae, or pseudohyphae are seen, this confirms the diagnosis^[3].

The vaginal pH is also typically measured. Candida vaginitis is associated with a normal vaginal pH of less than 4.5^[3]. This helps distinguish it from other types of vaginal infections that have higher pH levels.

If the microscopic examination is negative but symptoms suggest a yeast infection, your healthcare provider may order a fungal culture. Cultures are particularly important for women with recurrent infections because they can identify which specific species of Candida is causing the problem^[5]. Some species, like Candida glabrata, may be more resistant to standard treatments^[2].

It is important to note that finding Candida in a culture when you have no symptoms is not a reason for treatment, since approximately 10% to 20% of women naturally carry Candida species in the vagina^[3].

Classification of the Disease

Vulvovaginal candidiasis can be classified as either uncomplicated or complicated based on several factors including how often it occurs, how severe the symptoms are, which type of yeast is causing it, and the overall health of the affected woman^[3]. Approximately 10% to 20% of women will have complicated vulvovaginal candidiasis, which requires special diagnostic and treatment considerations^[3].

Uncomplicated vulvovaginal candidiasis is characterized by sporadic or infrequent infections with mild to moderate symptoms. These infections are likely caused by Candida albicans and occur in women who are not immunocompromised^[3].

Complicated vulvovaginal candidiasis includes several situations. One is recurrent vulvovaginal candidiasis, which is diagnosed when a woman has four or more specific episodes within one year or at least three episodes unrelated to antibiotic therapy within one year^[12]. This form is distinguished from persistent infection by the presence of a symptom-free interval between episodes^[12].

Complicated cases also include severe infections with extensive redness, swelling, and itching that leads to tears, cracks, or sores in the vagina^[4]. Infections caused by non-albicans Candida species, particularly Candida glabrata, Candida tropicalis, Candida krusei, Candida parapsilosis, and Candida guilliermondii, are considered complicated because these species may have resistance or decreased susceptibility to commonly used treatments^[5]. Non-albicans species are observed in 10% to 20% of women with recurrent vulvovaginal candidiasis^[7].

Women with diabetes, immunocompromising conditions such as HIV infection, underlying immunodeficiency, or those taking immunosuppressive therapy like corticosteroids are also classified as having complicated vulvovaginal candidiasis^[3].

Treatment

Antifungal medications are the main treatment for vulvovaginal candidiasis. These medications work by fighting yeast overgrowth in your body^[1]. Treatment approaches differ depending on whether the infection is uncomplicated or complicated.

For uncomplicated infections, short-course treatments are highly effective. These can be either topical (applied directly to the affected area) or oral (taken by mouth)^[3]. Treatment with azole antifungal medications results in relief of symptoms and negative cultures in 80% to 90% of patients who complete therapy^[3].

Many topical antifungal medications are available over the counter. These include clotrimazole, miconazole, and tioconazole in various forms such as creams, ointments, and suppositories^[3]. Treatment durations range from a single application to seven or fourteen days, depending on the specific medication and formulation used.

Prescription topical options include butoconazole and terconazole in cream or suppository form^[3]. The only oral antifungal medication commonly used for uncomplicated yeast infections is fluconazole, typically given as a single 150-mg dose^[3]. Patients are more likely to comply with oral therapy, though oral treatment carries a greater potential for drug interactions^[12].

For complicated or recurrent infections, longer treatment courses are often necessary. After the acute episode has been treated, subsequent preventive therapy (also called maintenance therapy) is important^[12]. Because many patients experience recurrences once preventive treatment is discontinued, long-term therapy may be needed^[12].

If you are using a vaginal medicine, you should not have sex until you have finished your treatment. If you do have sex during treatment, you should not depend on latex condoms or diaphragms for birth control because the oil in some vaginal medicines can weaken latex^[1].

It is important not to self-diagnose and self-treat without proper medical evaluation, especially if this is your first yeast infection or if symptoms do not improve after using over-the-counter treatments^[1]. Self-diagnosis is often inaccurate, and unnecessary use of antifungal medications can lead to delayed treatment of other conditions and may contribute to antifungal resistance^[5].

Prevention

While it may not be possible to prevent all yeast infections, you can take several steps to reduce your risk. Many preventive measures focus on maintaining good hygiene and avoiding factors that disrupt the natural balance of microorganisms in your vagina.

Clothing choices can make a difference. Wear cotton underwear and breathable clothing that is not too tight^[20]. Cotton allows air circulation and helps keep the genital area dry. Remove wet swimsuits and sweaty workout clothes promptly rather than sitting in them for extended periods^[18]. Some women find that sleeping without underwear can help^[1].

Proper genital hygiene is essential. Keep the vaginal area clean and dry using mild, unscented soap and water^[1]. Avoid douches and any kind of perfumed sprays, powders, or tampons, as these products can change the normal balance of organisms in your vagina^[1]. After using the bathroom, wipe from front to back to avoid spreading yeast or bacteria between your anus, urinary tract, or vagina^[1].

Diet may play a role in prevention. Diets high in sugar may be associated with a greater occurrence of yeast infections^[18]. Consider reducing foods and drinks made with sugars, such as soda and pastries, and replacing them with healthier options. Some evidence suggests that consuming foods containing probiotics, such as yogurt with live bacterial cultures, may help maintain a healthy balance of bacteria, though research is not yet conclusive^[18].

Only take antibiotics or corticosteroids as prescribed by a healthcare provider and take them exactly as directed^[20]. If you know you will be taking antibiotics, discuss with your doctor whether you should also take probiotics to help maintain bacterial balance^[18].

If you have diabetes, keeping your blood sugar levels under control is important for preventing yeast infections^[1]. Women with recurrent infections should work with their healthcare providers to identify and address any underlying health conditions or risk factors that may be contributing to repeated episodes.