Preterm low birth weight newborns are prone to complications during growth and development, such as growth retardation and infectious diseases, and the mortality rate of high-risk infants is higher than that of healthy newborns. Epidemiological data show that periodontal disease in pregnant women is correlated with preterm low birth weight. Periodontal disease in pregnant women is one of the risk factors for adverse pregnancy outcomes, such as  preterm   low birth weight. This paper addresses the correlation between maternal periodontal disease and  preterm  low birth weight, the influence of periodontal treatment on the incidence of preterm  low birth weight, and premature birth caused by maternal periodontal disease. The mechanism of infant weight is reviewed. The results of this review show that the current studies confirm the correlation between maternal periodontal disease and  preterm low birth weight. However, the causal relationship between maternal periodontal disease and preterm  low birth weight is not fully elucidated, and the specific mechanism and approach are not clear. A possible mechanism is that periodontal pathogens in pregnant women pass through the placental barrier to influence pregnancy outcomes. Therefore, more in-depth research is needed on the specific mechanism, approach, intervention and treatment based on the relationship between these two factors.