Does Pregnancy Have an Impact on the Subgingival Microbiota?

Abstract

Background: We investigated clinical and subgingival microbiologic changes during pregnancy in 20 consecutive pregnant women ≥18 years not receiving dental care. Methods: Bacterial samples from weeks 12, 28, and 36 of pregnancy and at 4 to 6 weeks postpartum were processed for 37 species by checkerboard DNA‐DNA hybridization. Clinical periodontal data were collected at week 12 and at 4 to 6 weeks postpartum, and bleeding on probing (BOP) was recorded at sites sampled at the four time points. Results: The mean BOP at week 12 and postpartum was 40.1% ± 18.2% and 27.4% ± 12.5%, respectively. The corresponding mean BOP at microbiologic test sites was 15% (week 12) and 21% (postpartum; not statistically significant). Total bacterial counts decreased between week 12 and postpartum ( P <0.01). Increased bacterial counts over time were found for Neisseria mucosa ( P <0.001). Lower counts ( P <0.001) were found for Capnocytophaga ochracea , Capnocytophaga sputigena , Eubacterium saburreum , Fusobacterium nucleatum naviforme , Fusobacterium nucleatum polymorphum , Leptotrichia buccalis , Parvimonas micra (previously Peptostreptococcus micros or Micromonas micros ), Prevotella intermedia , Prevotella melaninogenica , Staphylococcus aureus , Streptococcus anginosus , Streptococcus intermedius , Streptococcus mutans , Streptococcus oralis , Streptococcus sanguinis , Selenomonas noxia , and Veillonella parvula . No changes occurred between weeks 12 and 28 of pregnancy. Counts of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans ), Porphyromonas gingivalis , Tannerella forsythia (previously T. forsythensis ), and Treponema denticola did not change. Counts of P. gingivalis and T. forsythia at week 12 were associated with gingivitis ( P <0.001). Conclusions: Subgingival levels of bacteria associated with periodontitis did not change. P. gingivalis and T. forsythia counts were associated with BOP at week 12. A decrease was found in 17 of 37 species from week 12 to postpartum. Only counts of N. mucosa increased.