Periodontal Infection and Preterm Birth: Results of a Prospective Study

Abstract

Evidence from past studies suggests that chronic periodontal infection (chronic periodontitis) may be associated with preterm birth. Odds ratios as high as 7.9 are reported for mothers of preterm, low-birth-weight infants. The present prospective study correlated the presence of periodontitis at 21 to 24 weeks' gestation with subsequent preterm birth in 1313 women. Women requiring antibiotic prophylaxis for any reason were excluded. A team of specially trained dental hygienists obtained duplicate estimates of probe depth and attachment level in eight moderately affected nonpregnant patients and were accepted as study participants if their error did not exceed 0.5 mm. Significantly more periodontal disease was found in African American women than in white women. Unadjusted odds ratios for generalized periodontal disease increased with increasing prematurity, but this relationship did not take into account other known risk factors. Odds ratios adjusted for smoking, parity, race, and age disclosed that the risk of preterm birth associated with generalized periodontitis was approximately 4 to 7 times higher than in patients with good periodontal health. Women with severe or generalized periodontitis had an adjusted odds ratio of 4.45 for delivery before 37 weeks' gestational age, 5.3 for delivery before 35 weeks', and 7.1 for delivery before 32 weeks'. These findings support an association between preexisting maternal periodontal disease and preterm birth. A controlled interventional study will be needed to firmly establish a causal link.