The vaginal microbiome: Your body's own protective shield

The vagina is not a sterile space. It is a living ecosystem inhabited by billions of bacteria. Unlike the intestine, where diversity is desired, the opposite is true for the vagina: Healthy means that a certain group of bacteria dominates. Lactobacillus species are the most important inhabitants of a healthy vaginal flora.

These bacteria produce lactic acid, which keeps the vaginal pH low, typically between 3.8 and 4.5. This acidic value is no coincidence. It inhibits the growth of pathogens, protects against infections and keeps the mucous membrane healthy. If the balance tips and Lactobacillus bacteria are displaced by other germs, the pH rises and the risk of infection increases.

This balance is delicate. Hormonal changes, menstruation, sex, antibiotics, certain skincare products, or stress can affect it. This doesn't mean that an infection will occur immediately with any of these changes. But it does mean that the balance can be disrupted.

What keeps the microbiome healthy?

• •Lactobacillus-dominated flora, which produces lactic acid and keeps the pH low
• •No rinsing with intimate sprays or vaginal douches
• •Breathable cotton underwear
• •No perfumed care products directly at the vaginal opening
• •Urinate after sex to flush the urethra
• •Antibiotics only when necessary and possibly accompanied by probiotics

What is normal discharge – and what is not

Discharge is normal. Almost every woman has it, and it changes during the cycle. This is not a sign of poor hygiene or an illness, but rather an indication that the vagina is cleaning itself and reflecting the hormonal situation.

Normal discharge is clear to whitish, has a low odor or a slightly sour-milky smell, varies in amount depending on the cycle phase, and has no accompanying symptoms such as itching or burning. During the follicular phase and around ovulation, it often becomes more liquid and stringy, and in the luteal phase, it is more viscous and whitish.

When discharge can be a sign that something is wrong: if it suddenly smells distinctly different (fishy, sweet-fermented), if it is discolored green or yellow, if it is accompanied by itching, burning, redness or swelling, or if it is lumpy and cheese-like. The most common diagnoses are bacterial vaginosis, fungal infection or a sexually transmitted infection (STI).

The most common complaints: bacterial vaginosis and fungal infection

Bacterial vaginosis

Bacterial vaginosis (BV) occurs when the balance of the microbiome tips and Lactobacillus bacteria are displaced by other germs – particularly Gardnerella and related pathogens. It is the most common vaginal disease worldwide among women of reproductive age. Approximately one in four women are affected, many without knowing it, because BV often runs symptomless.

Typical signs are gray to whitish discharge with a fishy odor, which often becomes stronger after sex because semen increases the pH. Itching or burning is less common than with a fungal infection. BV is treated with antibiotics, but has a high relapse rate. Probiotics with Lactobacillus strains show promising results in studies for preventing relapses.

Yeast infection (Vulvovaginal candidiasis)

The fungal infection caused by Candida yeast is probably familiar to most people: whitish, curd-like discharge, severe itching, burning, and redness. Mushrooms are part of the normal vaginal flora in small amounts, but can grow excessively after antibiotic administration, during hormonal fluctuations, immunosuppression or due to persistent moisture and heat. Antifungal treatments are effective, but relapses are common.

Lichen Sclerosus: underestimated and often recognized late

Lichen Sclerosus (LS) is a chronic inflammatory skin disease that primarily affects the vulva and the anal area. It can occur at any age, but there are two peaks in frequency: in prepubertal girls and in women during and after menopause. Despite this, it takes an average of several years from the first symptoms to diagnosis – simply because LS is not well known and the symptoms are often confused with other diseases.

How does lichen sclerosus manifest itself?

The leading symptom is intense, persistent itching of the vulva, often worse at night. Additionally, there is burning, pain during sex (dyspareunia), and sometimes pain when urinating. The skin changes visibly: it becomes white, parchment-thin, and cracked. Over time, the small labia may fuse together and the vaginal opening may narrow, with significant effects on sexuality and quality of life.

The exact cause is not fully understood. An autoimmune component is considered to be certain: The immune system targets the body's own tissue. Hormonal factors, genetic predisposition, and local skin trauma also play a role. A low estrogen level, as is typical during menopause, promotes the development or worsening of the condition.

Why early treatment is important

Lichen sclerosus is not curable, but it can be well controlled. The standard treatment is high-potency topical corticosteroids (e.g., clobetasol propionate), which reduce inflammation and slow the progression of tissue changes. Untreated, LS slightly increases the risk of vulvar cancer – another reason to take the condition seriously and attend regular check-ups.

Important: Consistent treatment can significantly alleviate symptoms and stabilize the tissue architecture. Women who live with the symptoms for a long time without a diagnosis should know: there is help, and it is not a question of poor hygiene or imagination.

GUSM: Genitourinary Syndrome of Menopause

Genitourinary Syndrome of Menopause (GSM) is a collective term for a variety of complaints that arise from the drop in estrogen levels during menopause. Earlier, people simply spoke of "vaginal atrophy" – a term that only captured part of the picture and was stigmatizing for many women.

The drop in estrogen during peri- and post-menopause has far-reaching effects on the urogenital tissue. The vaginal mucosa becomes thinner, drier, and more sensitive. The pH level increases, the protective microbiome changes, and blood circulation decreases. At the same time, the urethra and bladder are estrogen-dependent, which explains why GUSM includes not only genital but also urological symptoms.

Typical symptoms of GUSM

Genital symptoms include vaginal dryness, burning and itching, pain or bleeding during sex, and an increased susceptibility to vaginal infections. Urological symptoms include frequent urge to urinate, pain when urinating, recurring urinary tract infections, and occasionally incontinence. Unlike hot flashes, which many women overcome over time, GUSM symptoms tend to get worse, not better, without treatment.

Approximately 50 to 70 percent of postmenopausal women are affected – but only a fraction discuss the issue with their doctor. The most common reasons are shame, the assumption that it is just a part of ageing, or simply a lack of awareness.

What helps with GUSM?

The good news: GUSM is treatable and the treatment is reliable.

Local (vaginal) estrogen therapy is the most effective option. Low-dose estrogen, applied directly to the vagina – as a cream, suppository, ring or tablet – works locally without significantly entering the bloodstream. It regenerates the mucous membrane, normalizes the pH value and reduces both genital and urological complaints. Even women who are not allowed to use systemic hormone therapy for oncological reasons can use local estrogen in many cases - this should be discussed with the treating physician on a case-by-case basis.

Vaginal moisturizers and lubricants (non-hormonal) can be used in addition. They alleviate dryness but do not correct the underlying tissue atrophy.

Women who accept GUSM symptoms as "inevitable aging" forgo effective help and often live for years with a reduced quality of life - including avoided sexuality, sleep disorders due to itching and frequent urinary tract infections. This doesn't have to be the case.

Practical tips

The vagina cleans itself. This is not a marketing slogan, but physiology. The penetration of water, soap or care products into the vagina disrupts the microbiome and increases the risk of BV and fungal infections. Cleaning the outer area (the vulva) with warm water is completely sufficient. Perfumed products, intimate sprays and vaginal showers do more harm than good.

Tight synthetic underwear, panty liners in constant use, and wet swimwear for an extended period can also disrupt the balance.

When to see a doctor: In case of unusual odour, changed colour of the discharge, itching, burning or pain. In case of persistent skin changes on the vulva (whitening, thickening, cracks). In case of recurring infections: If a fungal infection occurs for the third time in a year, it is worthwhile to clarify the underlying causes, such as diabetes or immune disorders. And instead of silently tolerating complaints during menopause – dryness, pain during sex, frequent bladder infections.

• •Less is more when it comes to care. Warm water for the vulva, no products inserted into the vagina. The body takes care of the rest itself.
• •Observe discharge. Learn what is normal for you. Changes in smell, color or accompanied by itching and burning are a reason for an examination.
• •Be careful with antibiotics. Probiotics (oral or vaginal) can help stabilize the vaginal flora faster after antibiotic treatment.
• •Take relapses seriously. If you frequently suffer from BV or fungal infections, you should look for triggers. Stress, hormonal changes, diet, and sexual behavior can all play a role.
• •Do not ignore changes to the vulva skin. Persistent itching, white spots or skin thickening should be checked out – even if it "only" feels like a minor issue.Lichen Sclerosus is treated better the earlier it is diagnosed.
• •Address menopause symptoms. GUSM is common, treatable, and not an inevitable fate. Local estrogen therapy is safe and effective. Talking to a gynecologist is worth it.

Don't forget the STI check. An STI screening is a must for new partners and unclear complaints. Many infections are symptomless and can only be detected by a test.

Sources

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