A recent NSW Public Health Bulletin article discussed

the possibility that periodontal infection may be a risk factor for preterm birth.1 One of the papers cited in support of this association was ‘Periodontal infection as a possible risk factor for preterm low birth weight ’ by Offenbacher et al.2 Such an association is potentially of major importance. In Australia, approximately seven per cent of births are preterm each year, and for many of these there is no known cause.3,4 Should an infectious cause be found, this would be a tremendously exciting result as, other than smoking, most risk factors for preterm birth are not modifiable. However, we believe the Offenbacher article provides only weak evidence, if any, of a causal association between periodontal disease and preterm birth because of significant methodological problems in the study. Offenbacher’s study results suggest that periodonta