Prolonged low-grade inflammatory state can be caused by chronic infections such as gingivitis, which is a common pathology seen in patients with PCOS. The primary etiological factor for periodontal diseases is microorganisms in the dental plaque, such as Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Aggregatibacter actinomycetemcomitans and Prevotella intermedia species, which can also be detected in saliva. Importantly, the effect of female steroid hormones on the composition of oral microbiota has been reported in puberty, menstruation, pregnancy and with oral contraceptive usage. Nevertheless, there is still limited information about the composition of oral microbiota, with regards to systemic inflammatory conditions triggered by hormonal disorders, such as PCOS. Taking into consideration that periodontal diseases are chronic infections that cause a low-grade chronic systemic inflammation it is plausible to consider an association with hormonal disorders, such as PCOS. The oral microbiota may trigger systemic antibody responses in patients with periodontal disease. It was previously shown that patients with chronic or aggressive periodontitis have higher serum anti-bacterial IgG antibodies compared to periodontally healthy individuals with no clinical signs of early-onset periodontitis. However, serum antibody responses to periodontal pathogens neither confer immunity against periodontal disease, nor are they considered as an auxiliary measure for the diagnosis of this disease. To the contrary there is evidence that the severity of periodontal disease may negatively correlate with local and systemic antibody titers to periodontal pathogens, such as P. gingivalis and A. actinomycetemcomitans. The carriage of these two species alone may be a determinant for their systemic antibody response, but not for the periodontal health status. On the other hand, the clinical definition of the periodontitis may be a crucial factor that can modify the association between P. gingivalis serum antibody titers and the disease. Because Protopine conspicuous differences exist in antibody titers to periodontal pathogens between periodontal health and disease, even after Geraniin successful periodontal therapy, the systemic antibody responses may mark the history of past periodontal infection.