Objective: To scrutinize the assumed association between chronic periodontal disease and preterm low birth weight (PTLB) infants. Design: Prospective study. Setting: Tanta University Hospital. Patients: The study incorporated 200 pregnant women in the first stage of labor of a single baby with intact membranes. A hundred women had definite preterm labor and delivered, later live infants whose birth weight were < 2500 g and 100 women with full term labor and delivered, later live infants weighting ≥ 2500 g. Intervention: All patients included in the study were subjected to history taking, general, obstetrical examination and periodontal evaluation. The levels of IL-6 and TNF-α were measured in gingival cervicular fluid, maternal serum and amniotic fluid using ELISA technique. Results: A significant association between chronic periodontal disease and preterm low birth weight infants. Conclusion: Screening of pregnant women chronic periodontal disease seems to be a helpful prediction and consequently prevention of preterm labour.