Background: Studies try to explain the hypothesis that maternal periodontitis may be associated with preterm birth.
Material and methods: This is a case-control study with 120, 40 cases (gestational age <37 weeks) and 80 controls (gestational age ≥37 weeks), that were submitted to the clinical periodontal examination and subgingival biofilm collection. Bacterial DNA of subgingival biofilm was performed and processed by qPCR.
Results: Periodontitis was statistically significant in the Case group (35%) when compared to the Control group (11.2%) and Gingival Bleeding Index (GBI), sites with PS ≥ 4mm and sites with CAL ≥ 5mm were statistically higher in the Case group (p < 0.05). The proportions of Pi (p = 0.026) and Fn (p = 0.041) of subgingival biofilm were higher in the Case group. A greater number of sites with PS ≥ 4mm (r = -0.202; p = 0.026) and CAL ≥ 5mm (r = -0.322; p < 0.001) were correlated to lower gestational age.
Conclusions: Periodontitis, preterm delivery, and/or low birth weight may have a possible relationship based on clinical parameters and the ratio of Pi and Fn at periodontal sites.