High Gingival Bleeding Burden in Late Pregnancy Is Associated with a Salivary Profile of Inflammatory, Regulatory, and Stress-Response Signals

Pregnancy increases susceptibility to gingival inflammation, and saliva may help characterize associated host-response profiles. This cross-sectional study compared nine salivary proteins and inflammatory mediators between pregnant women with high and low gingival bleeding burdens. Twenty-four women were classified by bleeding on probing (BOP) into G1 (BOP ≥ 50%; n = 12) and G2 (BOP < 30%; n = 12). Unstimulated saliva was collected, and RBP4, β2-microglobulin, clusterin, cystatin C, IL-1β, IL-6, IL-8, IL-10, and TNF-α were quantified using multiplex bead-based immunoassays. Primary comparisons used ANCOVA adjusted for maternal age and total protein concentration, with additional adjustment for visible biofilm in sensitivity analyses. In the primary adjusted analyses, G1 showed higher RBP4 (FDR-adjusted p = 0.004; partial η2 = 0.466) and clusterin (FDR-adjusted p = 0.006; partial η2 = 0.413), and lower IL-10 (FDR-adjusted p = 0.032; partial η2 = 0.285). In the sensitivity analyses, significant group effects were observed for RBP4 (FDR-adjusted p = 0.026; partial η2 = 0.381) and IL-8 (FDR-adjusted p = 0.044; partial η2 = 0.303). These findings demonstrate associations between high gingival bleeding burden and a salivary profile involving inflammatory/chemotactic, regulatory, and stress-response signals.