The vaginal ecosystem.

The ecology of vaginal flora is highly susceptible to numerous endogenous and exogenous influences. Possible mechanisms that might influence changes in the vaginal flora are microbial antibiosis, adhesion to the vaginal epithelial lining, e.g., availability of receptors, hormonal changes including physiologic alterations, disease states, drug therapy, sexual activity, and to a lesser extent, the immunologic status of the person. The role that these mechanisms may play in promoting vaginitis, vaginosis, and possibly pelvic inflammatory disease is explored.