Treatment of Periodontal Disease and the Risk of Preterm Birth

Abstract

Results of recent studies have suggested an association between periodontitis and several adverse pregnancy outcomes—preeclampsia, preterm birth, and low birth weight. Although the possibility that periodontal treatment during pregnancy may lessen the risk of preterm birth had been suggested by two previous single center clinical trials, a third study found no association between periodontal treatment and reduced preterm birth. This randomized, blinded trial, the Obstetrics and Periodontal Therapy (OPT) Study, randomly assigned women with periodontal disease, first seen at 13–17 weeks’ gestation, to have scaling and root planing either before 21 weeks’ gestation (n = 413) or following delivery (n = 410). Both ultrasonic and hand instruments were used to remove dental plaque and calculus from the tooth enamel and root. Women in the treatment group also had tooth polishing at monthly intervals and were instructed in oral hygiene. Most of the patients had generalized early-to-moderate periodontitis. The women who did and did not receive periodontal treatment did not differ significantly in gestational age at the end of pregnancy. The incidence of birth before 37 weeks’ gestation was 12.0% in the treatment group and 12.8% in the control group. Similar results were obtained after excluding spontaneous abortions and indicated preterm births, and after adjusting for baseline features. On competing-risks analysis, there were no group differences in the risk of live preterm birth, spontaneous abortion, or stillbirth. Serious adverse events, including hospital admission for any reason, were comparably frequent in the two groups. The treatment and control groups did not differ significantly with respect to birth weight or small-for-gestational-age births. Spontaneous abortions and stillbirths totaled 5 in the treatment group and 14 in the control group. Compared to postpartum treatment, treating periodontitis before 21 weeks’ gestation did not significantly increase the risk of preterm delivery in the OPT Study. The periodontal treatment was effective in promoting oral health, and did not produce serious complications or side effects.