ABSTRACT
<b>Background:</b> Female hormones may influence the oral environments of pregnant women. Appropriate oral care by pregnant women promotes oral health, contributing to caries prevention in children from the perspective of cariogenic bacteria transmission. The purpose of this study was to evaluate the oral environment of pregnant women and clarify factors associated with the presence of Streptococcus mutans.<br><b>Methods:</b> A saliva test (volume, pH, Streptococcus mutans count, Lactobacillus count, and total oral Streptococcus count) and questionnaire survey regarding subject characteristics, oral symptoms, and oral health behavior were conducted with 264 pregnant women. We examined the association between the saliva volume/pH and caries-associated bacteria, and compared oral environments related to differences in the subject characteristics, oral symptoms, and oral health behavior. Binomial logistic regression analysis was also conducted to clarify factors associated with the presence of Streptococcus mutans.<br><b>Results:</b> Oral cleanliness was maintained in the subjects who participated in this study. However, in 22.0% of these women, the Streptococcus mutans accounted for 1% or more of the total oral Streptococcus count. Eight items that reduced the proportion of Streptococcus mutans in the total Streptococcus count were confirmed and included the following: “tooth-brushing time of 5 minutes or more” ; “absence of tooth pain” ; “absence of stimulation related to sweets” ; “saliva pH of 6.8 or higher” ; “having a dental checkup for pregnant women” ; “consciously brushing teeth” ; “confidence in brushing” ; and, “employment (housework and full-time work) ”.<br><b>Conclusion:</b> The results of this study contribute to health education during pregnancy, in which health behavior may change as childbirth approaches, and may be useful for guiding appropriate oral health behavior.