Periodontal treatment did not prevent complications of pregnancy.

Design: A randomised controlled trial (RCT) was conducted.

Intervention: Women found to have a periodontal disease were randomly allocated to receive periodontal treatment in midpregnancy (this was the treatment group; n = 542) or after the pregnancy was concluded (the control group; n = 540). Periodontal disease was defined as presence of periodontal pockets of 4 mm or greater in depth at 12 or more probing sites in fully erupted teeth (typically excluding wisdom teeth). Treatments were conducted either by the hygienists or periodontists and included nonsurgical debridement of the subgingival and supragingival plaque, removal of local predisposing factors such as calculus, root planing, and adjustment of overhanging restorations. Comprehensive oral hygiene instructions and motivation were provided at each visit at a minimum of three weekly visits, with further visits if required.

Outcome Measure: The primary outcomes were preterm birth or other major complications of pregnancy.

Results: There were no differences between the control and treatment groups in terms of: preterm birth [9.3% compared with 9.7%; odds ratio (OR), 1.05; 95% confidence interval (CI), 0.7-1.58; P 0.81); birthweight (3450 g versus 3410 g; P 0.12); pre-eclampsia (4.1% versus 3.4%; OR, 0.82; 95% CI, 0.44-1.56; P 0.55); or other obstetric endpoints. There were four unexplained stillbirths in the control group and no pregnancy losses in the treated group (P 0.12). Measures of foetal and neonatal wellbeing were similar in the two groups, including abnormalities in foetal heart rate recordings (P 0.26), umbilical artery flow studies (P 0.96), and umbilical artery blood gas values (P 0.37). The periodontal treatment was highly successful in improving health of the gums (P<0.01).

Conclusions: The evidence provided by the present study does not support the hypothesis that treatment of periodontal disease during pregnancy in this population prevents preterm birth, foetal growth restriction, or pre-eclampsia. Periodontal treatment was not hazardous to the women or their pregnancies.