When Vaginal Balance Breaks: Understanding Bacterial Vaginosis and Its Clinical Impact

Bacterial vaginosis is the most common vaginal disorder in women of reproductive age. It is not caused by an external pathogen in the classic sense, but by a disruption of the delicate vaginal ecosystem. When protective mechanisms fail, opportunistic bacteria can dominate, leading to symptoms that range from mild discomfort to clinically significant reproductive risks.

A clear understanding of vaginal microbiology is essential for accurate diagnosis, effective treatment, and prevention of recurrence.

What Is Bacterial Vaginosis?

Bacterial vaginosis is a vaginal condition resulting from an imbalance of the normal saprophytic flora. In healthy individuals, the vaginal environment is dominated by lactobacilli, which maintain an acidic pH between 3.8 and 4.5 through lactic acid production. This acidity inhibits the growth of potentially pathogenic microorganisms.

In bacterial vaginosis, lactobacilli are reduced or lost, and anaerobic bacteria, most commonly Gardnerella vaginalis, proliferate excessively. The result is a shift toward a higher vaginal pH and the formation of a polymicrobial biofilm that adheres to the vaginal epithelium and resists host defenses.

This condition reflects dysbiosis rather than infection in the traditional sense.

Why Bacterial Vaginosis Develops

Bacterial vaginosis is not a sexually transmitted infection, nor is it caused by poor hygiene. On the contrary, practices that disrupt the vaginal microbiome are the main drivers of the condition.

Factors associated with bacterial vaginosis include:

Frequent intravaginal douching
Use of scented or aggressive intimate hygiene products
Insertion of intrauterine contraceptive devices
High frequency of sexual activity
Use of spermicidal agents
Pregnancy-related hormonal changes
Cigarette smoking
Regular use of daily absorbent pads
Washing underwear with strong detergents

These factors alter vaginal pH and reduce lactobacillary protection, creating an environment favorable for anaerobic bacterial overgrowth.

Symptoms and Clinical Manifestations

The hallmark symptom of bacterial vaginosis is abnormal vaginal discharge. This discharge is typically thin, gray-white, and watery, with a characteristic fish-like odor that may become more pronounced after sexual intercourse or during menstruation.

Additional symptoms may include:

Mild vulvar itching
Local burning sensation
Dysuria
Dyspareunia

Inflammatory signs are often minimal or absent, which distinguishes bacterial vaginosis from other vaginal infections. Despite mild symptoms, untreated bacterial vaginosis carries significant clinical risks.

Why Bacterial Vaginosis Should Not Be Ignored

Bacterial vaginosis is associated with increased susceptibility to sexually transmitted infections, including Chlamydia trachomatis and Neisseria gonorrhoeae. It also increases the risk of pelvic inflammatory disease.

During pregnancy, untreated bacterial vaginosis is linked to premature rupture of membranes, preterm birth, and low birth weight. These associations make early diagnosis and treatment clinically important even in mildly symptomatic cases.

Diagnosis of Bacterial Vaginosis

Diagnosis is established by a gynecologist based on patient history, clinical examination, and laboratory investigations.

Standard diagnostic methods include microscopic evaluation of vaginal secretions, identification of clue cells, and bacteriological culture. These investigations confirm the loss of lactobacilli and the predominance of anaerobic bacteria.

Treatment of Bacterial Vaginosis

Treatment aims to reduce anaerobic bacterial overgrowth and restore vaginal microbial balance. Standard therapy involves antimicrobial agents effective against anaerobic organisms, administered orally or intravaginally according to clinical context.

Adjunctive strategies focus on avoiding behaviors that disrupt the vaginal microbiome. Recurrence is common, reflecting the ecological nature of the condition rather than treatment failure.

Long-term management requires attention to vaginal health rather than repeated short-term antimicrobial courses alone.

Scientific references

1. Muzny CA, Schwebke JR. Pathogenesis of bacterial vaginosis: discussion of current hypotheses. Journal of Infectious Diseases. 2016;214(Suppl 1):S1–S5.

2. Srinivasan S, Fredricks DN. The human vaginal bacterial biota and bacterial vaginosis. Interdisciplinary Perspectives on Infectious Diseases. 2008;2008:750479.

3. Sobel JD. Bacterial vaginosis. Annual Review of Medicine. 2000;51:349–356.

4. Bradshaw CS, Brotman RM. Making inroads into improving treatment of bacterial vaginosis. BMC Infectious Diseases. 2015;15:292.

5. Hillier SL et al. Diagnosis and treatment of bacterial vaginosis. American Journal of Obstetrics and Gynecology. 1993;169(2):455–459.

6. Koumans EH, Kendrick JS. Preventing adverse sequelae of bacterial vaginosis. Clinical Microbiology Reviews. 2001;14(2):223–238.