Periodontal disease as a risk factor for pre-eclampsia: a case control study

OBJECTIVE: To investigate the association between periodontal disease and pre-eclampsia, while controlling known risk factors for pre-eclampsia. METHODS: A matched case-control study was carried out on 41 pre-eclamptic women and 41 normotensive, healthy, pregnant, control women. The pre-eclamptic women and controls were individually matched for age, gravidity, parity, smoking and prenatal care. The number of teeth and the number of restorations and decay on all tooth surfaces, and clinical periodontal parameters, excluding third molars were determined within 48 h before delivery. The relation of independent variables to pre-eclampsia was assessed using conditional multiple logistic regression analysis on subject-based data. RESULTS: There were no statistically significant differences in mean percentages of sites with plaque between groups. The mean probing depth (PD) and mean clinical attachment level (CAL) for pre-eclamptic patients were significantly greater compared to those of normotensive patients (P < 0.01). The percentage of sites exhibiting bleeding on probing (BOP) (P < 0.05), the number of sites with PD >/= 4 mm and with CAL >/= 3 mm was significantly higher among pre-eclamptic patients than those with normotensive patients (P < 0.01). Conditional multiple logistic regression analysis indicated that periodontal disease and triglycerides level were significantly associated with pre-eclampsia. Other independent variables (maternal body weight and serum total cholesterol level) did not appear to be associated with pre-eclampsia. Conditional multiple logistic regression results showed that pre-eclamptic patients were 3.47 (95% CI = 1.07-11.95) times more likely to have periodontal disease than normotensive patients. CONCLUSION: The present study shows that maternal periodontal disease during pregnancy is associated with an increased risk for the development of pre-eclampsia. The higher incidence of periodontal disease parameters in pre-eclamptic group would suggest a possible role for periodontal disease in the development of pre-eclampsia. The nature both of periodontitis and pre-eclampsia is multifactorial, and caution should be exercised when implicating periodontal disease in causation of pre-eclampsia.