Causes of Bacterial Vaginosis

The etiology of bacterial vaginosis (BV) is multifactorial. It may result from poor external genital hygiene leading to bacterial infection, or from unhygienic sexual practices causing vaginal infection. Additionally, declining estrogen levels can cause vaginal epithelial atrophy, thereby predisposing women to BV. Therefore, the causes of bacterial vaginosis are numerous, and it is essential for women to understand these underlying factors and adopt appropriate preventive and self-care measures. Below, we provide a detailed overview of the causes of bacterial vaginosis!

Causes of Bacterial Vaginosis

1. Declining Estrogen Levels Leading to Vaginal Epithelial Atrophy

Urethritis is a common clinical condition, categorized into acute and chronic bacterial urethritis. The most frequently implicated pathogens in bacterial urethritis include Escherichia coli, streptococci, and staphylococci.

2. Reduced Cellular Glycogen

Reduced glycogen content in vaginal epithelial cells—often seen in elderly women—impairs the growth of Lactobacillus. This may be exacerbated by excessive use of antibiotics or overzealous vaginal douching with alkaline solutions. Associated factors include vaginal wall atrophy, mucosal thinning, ovarian insufficiency, decreased estrogen levels, elevated vaginal pH, and diminished local immunity.

3. Indirect Contact Transmission

Indirect contact is one route of transmission for bacterial vaginosis. Sharing contaminated public facilities—such as toilet seats, bathtubs, communal shower benches, or towels—or using unclean toilet paper may facilitate transmission. Therefore, avoiding shared personal items is strongly advised.

4. Sexual Transmission

Sexual transmission is another contributing factor. Among male partners of symptomatic female patients, at least 10% may harbor bacterial urethritis; thus, concurrent treatment of both partners is recommended to prevent recurrent or cross-infection. Practicing safe sex and maintaining personal sexual hygiene are crucial preventive measures.

5. Decreased White Blood Cell Count

Leukopenia is a common hematologic disorder. It is defined as a persistent peripheral blood white blood cell count below 4 × 10⁹/L. When the total white blood cell count drops markedly—to less than 2 × 10⁹/L—and the absolute neutrophil count falls below 0.5 × 10⁹/L (or even becomes undetectable), the condition is termed agranulocytosis.

6. Inappropriate Antibiotic Use

Excessive or indiscriminate antibiotic use suppresses protective Lactobacillus species in the vagina, disrupting its natural microbial equilibrium and compromising the local microenvironment. This disturbance may precipitate gynecologic infections—including candidal vaginitis—and contributes to the development of bacterial vaginosis.

7. Over-Cleansing

Excessive hygiene practices can also trigger bacterial vaginosis. While routine use of mild feminine hygiene washes is generally acceptable, some women resort to frequent intravaginal douching with medicated solutions in an effort to enhance cleanliness. Such practices readily disrupt the vagina’s natural acidic pH balance, not only failing to eliminate pathogens but actually increasing susceptibility to bacterial vaginosis.

The above outlines the principal etiologic factors associated with bacterial vaginosis. We hope this information proves helpful to you.