Association of Chlorhexidine Use and Scaling and Root Planing With Birth Outcomes in Pregnant Individuals With Periodontitis: A Systematic Review and Meta-analysis.

Importance: Chlorhexidine mouthwash enhances treatment effects of conventional periodontal treatment, but data on chlorhexidine as a source of heterogeneity in meta-analyses assessing the treatment of maternal periodontitis in association with birth outcomes are lacking. Objective: To assess possible heterogeneity by chlorhexidine use in randomized clinical trials (RCTs) evaluating the effect of periodontal treatment (ie, scaling and root planing [SRP]) vs no treatment on birth outcomes. Data Sources: Cochrane Oral Health's Trials Register, Cochrane Pregnancy and Childbirth's Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid, Embase Ovid, LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database), US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov), and the WHO International Clinical Trials Registry Platform were searched through March 2022. Study Selection: RCTs were included if they were conducted among pregnant individuals with periodontitis, used interventions consisting of SRP vs no periodontal treatment, and assessed birth outcomes. Data Extraction and Synthesis: Data were abstracted with consensus of 2 reviewers using Rayyan and assessed for bias with the Cochrane Risk of Bias 2 tool before random effects subgroup meta-analyses. Analyses were conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline. Main Outcomes and Measures: Outcomes of interest were preterm birth (ie, <37 weeks' gestation) and low birth weight (ie, <2500 g). Results: There were 12 studies with a total of 5735 participants evaluating preterm birth. Control group participants did not receive any treatment or use chlorhexidine during pregnancy. All intervention group participants received SRP; in 5 of these studies (with 2570 participants), pregnant participants in the treatment group either received chlorhexidine mouthwash or advice to use it, but participants in the remaining 7 studies (with 3183 participants) did not. There were 8 studies with a total of 3510 participants evaluating low birth weight, including 3 studies with SRP plus chlorhexidine (with 594 participants) and 6 studies with SRP only (with 2916 participants). The SRP plus chlorhexidine groups had lower risk of preterm birth (relative risk [RR], 0.56; 95% CI, 0.34-0.93) and low birth weight (RR, 0.47; 95% CI, 0.32-0.68) but not the SRP-only groups (preterm birth: RR, 1.03; 95% CI, 0.82-1.29; low birth weight: RR, 0.82; 95% CI, 0.62-1.08). Conclusions and Relevance: These findings suggest that treating maternal periodontitis with chlorhexidine mouthwash plus SRP was associated with reduced risk of preterm and low birth weight. Well-conducted RCTs are needed to test this hypothesis.