Fusobacterium nucleatum and adverse pregnancy outcomes: Epidemiological and mechanistic evidence

Abstract

Fusobacterium nucleatum is a Gram-negative anaerobic oral commensal associated with periodontal disease. F. nucleatum has been implicated in a wide spectrum of systemic diseases, including oral, gastro-intestinal, rheumatologic, and vascular pathologies. As pregnancy risk has been linked to periodontal disease, there has also been significant research into the effects of periodontal disease on adverse pregnancy outcomes. This article reviews the epidemiological and mechanistic evidence of the role of F. nucleatum in adverse pregnancy outcomes.

Keywords: Chorioamnionitis; FadA; Fusobacterium nucleatum; Neonatal sepsis; Oral anaerobe; Placenta; Pregnancy complications; Preterm birth; Stillbirth; VE-cadherin.

Fig. 1

Schematic presentation of oral bacteria translocation to the fetal-placental unit. Bacteria enters the circulation through the inflamed gingival tissue (a) and (b). Hematogenously spread bacteria invade the fetal-placental unit through the vasculature in the decidua basalis (c) and (d). Binding of Fusobacterium nucleatum adhesin A (FadA) to vascular endothelial cadherin (VE-cadherin) increases the endothelial permeability, allowing F. nucleatum and other oral bacteria to disseminate into and from the circulation (b) and (c).