Objectives: To determine whether there is an association between maternal periodontitis and premature low birth-weight newborns (PLBW) in a New Zealand population. Methods: Approximately 6% of all babies in New Zealand are born prematurely, resulting in a large proportion of infant morbidity and major medical, social and economic sequelae. Recent work suggests that maternal infection is a key aetiological factor. A retrospective clinical case-control investigation recruited 60 mothers from Queen Mary Maternity Unit, Dunedin, New Zealand: 30 in the cohort group and 30 in the control group. Test subjects were defined as any mother who had delivered a PLBW infant (birth-weight <2,500g and delivered at <35 weeks gestation). The control subjects were randomly selected from those who had ‘normal' deliveries (>2,500g and delivered at >38 weeks gestation) and were matched for ethnicity and age (±5 years) to the cohort group. A questionnaire recorded demographics, medical and pregnancy history data. Periodontal and radiographic examinations were then performed using a split-mouth protocol. Results: Analysis of preliminary results demonstrated a significantly higher percentage of PLBW subjects (60%) with mild periodontitis (defined as 1-4 sites >4mm PD) compared with the control group (40%, p=0.001). A similar trend was seen with moderate-severe periodontitis (defined as 5+ sites with >4mm PD) - 78.6% PLBW versus 21.4% control group (p=0.001). After adjusting for other known risk factors using a conditional logistic regression model, women were found to be at higher risk of delivering a PLBW newborn if they exhibited either mild (OR 4.0, 95%CI 0.57-19.4) or moderate-severe (OR 9.8, 95%CI 0.66-131.5) periodontitis. Conclusion: This is the first investigation of its kind to be conducted within New Zealand and preliminary results strongly support the need for interventional trials. Further retrospective studies limited to Maori and Pacific Island populations would also be useful.