Skip to main content
Toggle Menu of ADA WebSites
ADA Websites
Partnerships and Commissions
Toggle Search Area
Toggle Menu
e-mail Print Share
Science in the News

Association Between Maternal Periodontitis and Adverse Pregnancy Outcomes Explored

September 28, 2017

The relationship between maternal periodontitis and adverse pregnancy outcomes has been investigated in many studies in recent years. Periodontal disease is common during pregnancy and although it has been linked to adverse pregnancy outcomes such as low birthweight and pre-eclampsia, systematic reviews attempting to clarify these associations have reached mixed conclusions. Daalderop and colleagues1 performed a recent synthesis of findings from systematic reviews (“overview of reviews”) assessing the link between periodontal disease and a range of adverse pregnancy outcomes, focusing on interpretation of findings from high-quality reviews.

The systematic review research protocol was peer-reviewed and published2 and had been registered with the PROSPERO international prospective register of systematic reviews (PROSPERO: CRD42015030132).  Registration with PROSPERO helps to avoid research duplication and reduces opportunity for reporting bias by allowing a comparison of the completed review with what was planned in the protocol.

Six online literature databases were electronically searched through November 2016; references and citations of eligible papers were manually searched. Systematic literature reviews comparing pregnancy outcomes among women with and without periodontal disease were considered eligible for inclusion. The primary health outcomes assessed were maternal mortality, preterm birth, and perinatal mortality; secondary outcomes included miscarriage, premature rupture of membranes, pre-eclampsia, and low birthweight. Two reviewers performed data abstraction and assessed the risk of bias of individual systematic reviews.

Twenty-three systematic reviews (each including between 3 and 45 studies) were included in the overview. None of the systematic reviews reported the association between periodontal disease and maternal or perinatal mortality. Systematic reviews with the lowest risk of bias consistently demonstrated positive associations between periodontal disease and risk of preterm birth (relative risk [RR], 1.6; 95% confidence interval [CI], 1.3 to 2.0; 17 studies, N=6,741), low birthweight (RR, 1.7; 95% CI, 1.3 to 2.1; 10 studies, N=5,693), pre-eclampsia (odds ratio [OR], 2.2; 95% CI, 1.4 to 3.4; 15 studies, N=5,111), and preterm low birthweight (RR 3.4; 95% CI, 1.3 to 8.8; 4 studies, N=2,263). In terms of limitations, the authors noted that as several primary studies did not adjust for confounding, meta-analyses may have overestimated the strength of the associations being studied. Because of “substantial overlap” in the included primary studies, researchers were unable to aggregate results across reviews. They concluded, “Consistent evidence from systematic reviews with low risk of bias indicates that pregnant women with periodontal disease are at increased risk of developing preeclampsia and delivering a preterm and/or [low birthweight] baby,” and that “Research is needed to develop novel preventive and treatment strategies.”


  1. Daalderop LA, Wieland BV, Tomsin K, et al. Periodontal Disease and Pregnancy Outcomes: Overview of Systematic Reviews. JDR Clinical & Translational Research 2017;Online ahead of print.
  2. Vanterpool SF, Tomsin K, Reyes L, et al. Risk of adverse pregnancy outcomes in women with periodontal disease and the effectiveness of interventions in decreasing this risk: protocol for systematic overview of systematic reviews. Syst Rev 2016;5:16.

Prepared by: Center for Scientific Information, ADA Science Institute

About Science in the News

Science in the News is a service by the American Dental Association (ADA) to its members to present current information about science topics in the news. The ADA is a professional association of dentists committed to the public's oral health, ethics, science and professional advancement; leading a unified profession through initiatives in advocacy, education, research and the development of standards. As a science-based organization, the ADA's evaluation of the scientific evidence may change as more information becomes available. Your thoughts would be greatly appreciated.

Content on is for informational purposes only, is neither intended to and does not establish a standard of care, and is not a substitute for professional judgment, advice, diagnosis, or treatment. ADA is not responsible for information on external websites linked to this website.