Periodontal diseases and the risk of preterm birth and low birth weight: a meta-analysis

BACKGROUND: This meta-analysis of periodontal disease in relation to the risk of preterm birth/low birth weight (PTB/ LBW) is based on two case-control studies and three prospective cohort studies that met pre-stated inclusion criteria. METHODS: Information on the designs of the studies, characteristics of the study population, exposure and outcome measures, control for confounders, and risk estimates were abstracted independently by two investigators using a standard protocol. RESULTS: Pregnant women with periodontal disease had an overall adjusted risk of preterm birth that was 4.28 (95% confidence interval [CI], 2.62 to 6.99; P <0.005) times that risk for healthy subjects. The overall adjusted odds ratio of preterm low birth weight was 5.28 (95% CI, 2.21 to 12.62; P <0.005), while the overall adjusted odds ratio of a delivery of either PTB or LBW was 2.30 (95% CI, 1.21 to 4.38; P <0.005). CONCLUSIONS: Our findings indicate that periodontal diseases in the pregnant mother significantly increase the risk of subsequent preterm birth or low birth weight. While it remains important to promote good oral hygiene during routine prenatal visits, there is no convincing evidence, on the basis of existing case control and prospective studies, that treatment of periodontal disease will reduce the risk of preterm birth. Consequently, large randomized, placebo-controlled, masked clinical trials are required.