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Does the frequency of Prevotella intermedia increase during pregnancy?

M Gürsoy1, G Haraldsson, M Hyvönen

  • 1Department of Bacterial and Inflammatory Diseases, National Public Health Institute (KTL), Mannerheimintie 166, Helsinki 00300, Finland. mervi.latva-aho@ktl.fi

Oral Microbiology and Immunology
|July 4, 2009
PubMed
Abstract

Insights

Pregnancy gingivitis is linked to Prevotella nigrescens, not Prevotella intermedia. This study found P. nigrescens increases during pregnancy, correlating with gingivitis symptoms.

Area of Science:

  • Oral microbiology
  • Periodontology
  • Microbial diagnostics

Background:

  • Hormone-induced pregnancy gingivitis is associated with the bacterial group formerly known as Bacteroides intermedius.
  • This group now includes Prevotella intermedia and Prevotella nigrescens.

Purpose of the Study:

  • To determine if Prevotella intermedia, Prevotella nigrescens, or both species contribute to the microbial shifts observed during pregnancy gingivitis.

Main Methods:

  • Longitudinal study of 30 pregnant women and 24 non-pregnant controls.
  • Subgingival plaque and saliva samples analyzed for pigmented gram-negative anaerobes.
  • Phenotypic testing followed by 16S ribosomal DNA-based polymerase chain reaction (PCR) for species identification.

Main Results:

  • A significant increase in Prevotella intermedia sensu lato was observed in plaque during the second trimester of pregnancy, correlating with gingivitis.
  • The vast majority of identified isolates were Prevotella nigrescens (95.3%), with fewer Prevotella intermedia (2.5%).
  • Post-delivery, gingival inflammation decreased, but Prevotella intermedia sensu lato transiently increased in plaque and saliva.

Conclusions:

  • Prevotella nigrescens is a common finding in the oral cavity of young women without periodontitis.
  • Pregnant women show increased levels of Prevotella nigrescens, which is likely associated with pregnancy gingivitis.

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