Pathophysiology of preterm birth: emerging concepts of maternal infection.

Preterm birth remains a significant health concern. Maternal reproductive infections such as bacterial vaginosis pose increased risk for preterm birth, although treatment of bacterial vaginosis has not proven to be universally effective in preterm birth prevention. Maternal oral infection such as clinical periodontal disease has also been identified as a risk factor for preterm birth, and pilot data suggest that oral treatment interventions undertaken during pregnancy may reduce preterm birth risk.