Bacterial vaginosis occurs when:

Bacterial vaginosis occurs when normal bacteria in the vagina are replaced by an overgrowth of other bacterial forms. This condition is characterized by an imbalance of the natural flora in the vagina, where beneficial bacteria, primarily lactobacilli, are diminished and replaced by other types of bacteria, such as Gardnerella vaginalis.

This overgrowth can lead to various symptoms, including increased discharge, a fishy odor, and irritation, but it is important to note that many individuals may be asymptomatic. The disruption of the normal bacterial ecosystem is the core issue in bacterial vaginosis, making it distinct from infections caused by harmful bacteria that specifically target and damage reproductive organs or cause more severe symptoms. Understanding this is key as it helps differentiate bacterial vaginosis from other types of infections that can have more acute or severe clinical presentations.