The normal female vagina is colonised by bacteria, predominantly lactobacilli which maintain an acidic pH, typically less than 4.5. An alteration in the normal flora can occur with increased growth of other bacterial species. This leads to bacterial vaginosis (BV) wherein the individual experiences foul smelling, off-white vaginal discharge.
Bacterial Vaginosis is the most common cause of vaginitis (inflammation of the vagina) in women in the reproductive age group. BV is not classified as a sexually transmitted Infection (STI), as there is no single organism or male component of the disease identified so far. However, there is an association with sexual activity. In addition, women who have never been sexually active have not been known to have BV.
Although bacteria are implicated in causing the disease, there is no single organism which has been identified as leading to BV. One bacterial species, Gardnerella vaginalis is found to have a significant role in causing BV by forming a biofilm (a thin layer containing bacteria which coats other structures and protects the bacteria from being attacked by external elements) around the vagina, allowing other bacterial species to survive and cause vaginitis.
Between 50 to 75% of women with BV are asymptomatic.
Bacterial Vaginosis is diagnosed following a physical exam, including a pelvic examination and a few laboratory tests.
Bacterial Vaginosis is treated using antibiotics. The two most common drugs used are metronidazole and clindamycin. These are available as pills, gels or creams to be used locally in the vagina. The mode of treatment depends on the individual.
Male partners do not require treatment. Female partners should be notified of the infection in order to be prepared for treatment, should they show symptoms.