Chronic periodontitis has been acknowledged as a potential risk factor for adverse pregnancy outcomes and it has been suggested that biological mechanisms involving periodontal inflammation might play an important role here.
As explained in the scientific paper The biological mechanisms between periodontal diseases and pregnancy complications , written especially for the EFP/Oral-B Oral Health and Pregnancy project, clinical studies suggest that bacteria from the oral cavity colonise the foetus and the placenta, with blood the most likely vehicle of transmission.
The authors of the paper – Prof Filippo Graziani of the University of Pisa (Italy) and Dr Mervi Gürsoy of the University of Turku (Finland) – explain that, although specific micro-organisms associated with periodontitis have been associated with adverse pregnancy outcomes, little is yet known about the exact role they might play.
On top of that, it is not yet understood why some women with periodontal inflammation develop adverse pregnancy outcomes and others do not.
A second paper written for the Oral Health and Pregnancy project covering the same topic, A systematic review and meta-analysis of epidemiological association between adverse pregnancy outcomes and periodontitis: an update of the review of Ide & Papapanou (2013), points out: “There is still no clear evidence to support the association between maternal periodontal disease and adverse pregnancy outcomes.”
This paper, written by Morena Petrini, Stefano Gennai, and Laura Bettini of the University of Pisa together with Prof Graziani and Dr Gürsoy, says that contradictory findings been reported and that the available literature is “too heterogenous to be able to draw solid and definitive conclusions.”
The authors add that while some studies show that there might be an association between adverse pregnancy outcomes and periodontitis, the strength of this association is “extremely limited”. They note that for all the research papers that do indicate association, an equal number of studies do not.
“Periodontal diseases have been associated with adverse pregnancy outcomes such as low-weight birth, pre-term birth, and even pre-eclampsia,” said Prof Graziani. “But we don’t really know why and we are still trying to understand what is going on.”
He emphasised that further studies are needed to improve our understanding of the complex biological processes that are involved in the relationship between periodontal disease and pregnancy complications.