Attaching to the surface of multilayered planar epithelium, Gardnerella are able to form characteristic formations,
which in clinical practice are called"key cells".
While the infection involves a number of bacteria,
it is believed that most infections start with Gardnerella vaginalis creating a biofilm,
which allows other opportunistic bacteria to thrive.
There is also evidence that bacterial vaginosis can be associated with chorionamnionitis(a purulent-septic complication that also leads to premature birth), and,
according to some experts, a Gardnerella can trigger postpartum or post-abortion sepsis.