Purpose: The aim of the present study was to analyse the role of the main diagnostic signs of poor periodontal status, probing depth (PD) ≥4 mm and bleeding on probing (BOP) ≥50%, both simultaneously and individually in preterm birth (PB) and their effect on the birth weight (BW). Prematurity is a major health concern and it is the leading contributing factor to neonatal morbidity and mortality worldwide. Conflicting results exist on the relation between poor maternal, periodontal status and adverse pregnancy outcome, including preterm deliveries and low birth weight (LBW). Materials and Methods: Seventy-seven PBs and 165 deliveries at term were analysed out of 242 patients. The perinatal factors such as gestational age (GA) and BW were analysed by BOP, categorised as ≥50% (high BOP) vs <50% (non-high BOP) and PD ≥4 mm vs <4 mm, in combination or separately. Results: The obtained results suggest that maternal periodontal inflammation, represented particularly by BOP, might be a triggering factor and can be associated with PB and LBW. For women with high BOP the adjusted odds ratio (AOR) for LBW was 2.28-fold and they were likely to have PB, with a 2.02-fold higher rate. Conclusion: An increasing tendency of BOP seemed to be associated with a tendency to PB and LBW. Further investigations are necessary to underline this relationship, but the role of good oral health status in general, and particularly in case of pregnancy, is unequivocal.