Relationship between periodontal disease and preterm birth. A systematic review and meta-analysis

Periodontal disease (PD) is a chronic inflammatory disease of multifactorial origin that affects the supporting tissues of the tooth. According to WHO in 2022, it affects around 19% of the adult population worldwide. Its risk factors include the presence of periodontopathogenic bacteria in biofilm and the susceptibility of the host's immune system, among others. Preterm birth is defined as birth occurring before 37 weeks of gestational age. It also has a multifactorial origin and it's associated with risk factors such as intrauterine and extrauterine infections. There is a possibility that periodontal disease in pregnant women increases the risk of preterm birth through hematogenous pathways or the presence and intervention of inflammatory mediators.

Through a systematic review of existing scientific articles from 2014 to 2024, five randomized clinical trials were selected, including a total of 1984 pregnant patients diagnosed with periodontal disease. Half of these patients received non-surgical treatment, while the other half did not, aiming to evaluate a possible association between periodontal disease and/or its treatment and the occurrence of preterm birth. The risk of bias was assessed using the Cochrane "RoB 2" tool, and finally, a meta-analysis was conducted to compare the results obtained in the selected studies.

Four articles showed a trend favoring non-surgical periodontal treatment as a preventive measure for preterm birth. These articles accounted for 92.2% of the total weight, while the remaining 7.85% corresponded to the single article that did not favor the treatment. However, none of the articles showed statistically significant results.

There is no demonstrated association between periodontal disease in pregnant women and the incidence of preterm birth. On the other hand, there is a slightly favorable trend towards non-surgical periodontal treatment during pregnancy as a measure to reduce the incidence of preterm birth, but it's not statistically significant. To obtain a definitive answer, more randomized clinical trials following similar study and design parameters are needed.