The Salivary Microbiome During Pregnancy: Associations With Clinical and Sociodemographic Characteristics.

Purpose: Poor oral health has been associated with adverse pregnancy outcomes, and the oral microbiome may play a role in these mechanisms. We aimed to examine the salivary microbiome for alterations in diversity or relative abundance throughout pregnancy and its associations with adverse pregnancy outcomes and sociodemographic characteristics.

Study design and methods: We conducted an ancillary study from a previous cohort study of 37 women during their second and third trimesters of pregnancy using preexisting, participant-collected salivary samples to examine the oral microbiome using 16S rRNA sequencing.

Results: The salivary microbiome demonstrated stability throughout pregnancy, as there were no significant differences in alpha or beta diversity. Individuals who were diagnosed with preeclampsia had differences in beta diversity at the genus level (F = 2.65, df = 1, P = .015). There were also differences in beta diversity at the species level in Hispanic individuals compared with non-Hispanic individuals (F = 1.7183, df = 1, P = .04).

Conclusion: The salivary microbiome demonstrated stability throughout the second and third trimesters but may be different in Hispanics or those diagnosed with preeclampsia. As such, clinical providers need to demonstrate culturally competent care during pregnancy and continue to educate women about the importance of oral healthcare during the perinatal period. Future research is needed to examine the mechanisms associated with oral microbiome dysbiosis in Hispanic women during pregnancy and in women with preeclampsia.