Periodontal status and preterm low birth weight: a case control study.

Background:  Previous studies have suggested that periodontal disease may be an important risk factor for preterm low birth weight. However, the link between periodontal health status of pregnant women and preterm low birth weight is contentious, as recent studies found no association between periodontitis and pregnancy outcome. Objective:  The aim of this study was to investigate this potential link in a German Caucasian population. Methods:  Fifty-nine pregnant women with a high risk for a preterm low birth weight infant (suffering from preterm contractions, cases, group 1) as well as 42 control women with no preterm contractions during pregnancy and having an infant appropriate for date and weight (≥ 37 weeks gestation, ≥ 2500 g, group 2) were examined. Clinical periodontal status was recorded on a full mouth basis. Subgingival plaque samples were taken and periodontal pathogens were identified by polymerase chain reaction. Additionally, interleukin-1β level in gingival crevicular fluid was analysed. Results:  The mean percentage of sites showing moderate to advanced attachment loss (≥ 3 mm) was low in all study groups (group 1: 9.9 ± 11.2%; group 2: 10.6 ± 14.1%, respectively). No significant differences between the groups in any aspects of the studied periodontitis parameters could be detected. Using a logistic regression model controlling for known preterm low birth weight risk factors, no periodontitis-associated factors increased risk for preterm contractions or preterm low birth weight. The odds ratio (OR) was 1.19 for preterm contractions, the 95% confidence interval (CI) 0.46; 3.11 and 0.73 for preterm low birth weight; 95% CI: 0.13; 4.19, respectively. Conclusion:  In this population, periodontitis was not a detectable risk factor for preterm low birth weight in pregnant women.