Levels of periodontal pathogens in neonatal gastric aspirates and possible maternal sites of origin.

Maternal periodontal infection has been recognized as a risk factor for preterm and low birthweight infants. It is suspected that pathogens causing periodontal disease may translocate to the amniotic cavity and so contribute to triggering an adverse pregnancy outcome. This study aimed to determine levels and proportions of periodontal bacteria in neonatal gastric aspirates obtained from complicated pregnancies and the respective maternal oral and vaginal samples using a quantitative polymerase chain reaction approach, and also to determine the origin of the neonate's bacteria by sequence comparisons between the three sites. Aggregatibacter actinomycetemcomitans and Tannerella forsythia were not observed in the neonates or in the women's vaginas. Interestingly, Porphyromonas gingivalis was identified in the neonates in two samples (2.98E+02 and 1.75E+02 cells ml(-1)) and in association with Fusobacterium nucleatum, which was observed at high prevalence (10%) and at high levels reaching up to 2.32E+03 cells ml(-1). Although F. nucleatum was also present in the vaginal samples, the results demonstrated that the neonatal strains were more likely to originate from the mother's oral cavity than to be vaginal strains.