Periodontal Health Trajectories across Trimesters in Pregnant Women Compared to Non-pregnant Controls: A Multicenter Cross-Sectional Study.

Aim: Pregnancy-induced hormonal shifts can exacerbate periodontal disease, yet trimester-specific data, especially from sub-Saharan populations, are scarce. This study assessed and compared periodontal status and treatment needs between pregnant and non-pregnant women in the Democratic Republic of the Congo, with attention to changes across trimesters. Materials and Methods: A multicenter cross-sectional study included 307 pregnant women and 309 age-matched non-pregnant controls. Standardized clinical indices, including oral hygiene index-simplified, bleeding on probing, periodontal pocket depth (PPD), clinical attachment loss, and community periodontal index of treatment needs (CPITN) were used. Data were analyzed using Chi-square tests, t tests, and multivariate logistic regression. Results: Pregnant women exhibited significantly worse periodontal health. A higher proportion of pregnant women had PPD > 4 mm (26% vs. 19%, P = 0.049) and required advanced periodontal treatment (CPITN treatment need III: 26% vs. 18%, P = 0.013) compared to non-pregnant controls. Periodontal disease severity progressed with gestation: localized gingivitis peaked in the second trimester (50%), while periodontitis was most prevalent in the third trimester (59%). After adjusting for confounders, gestational status was independently associated with higher odds of periodontitis (OR = 2.87, 95% CI: 1.06-7.91). Conclusion: Pregnancy is significantly associated with deteriorating periodontal health and increased treatment needs, particularly in the second and third trimesters. These findings underscore the urgent need to integrate trimester-specific periodontal screening and preventive care into routine antenatal services to improve maternal oral and systemic health.