Abstract: Objective To explore the degree of continuity of birth defect prevention service and its influence on the effect of birth defect prevention in Guangzhou.Methods Four sample districts of Guangzhou were randomly selected to conduct an field questionnaire survey on the leaders in charge of the district health and family planning bureau,3 tertiary health care institutions and 2 secondary health care institutions and the patients in these institutions.Results 66.67% of the medical service providers can share the patient information of pre-marital,pre-pregnancy,prenatal consultation and examination with other medical institutions. 76.82% of medical service providers believed that the clinical reception efficiency was high. Prenatal screening status,proportion of projects completed before and during the first trimester of pregnancy for folic acid prevention of neural tube defects,integrity of information transfer between institutions on pre-marital,pre-pregnancy,prenatal consultation and examination,mutual recognition on the medical examination results were ranked in the top three factors of the continuity of medical and health information transmission respectively.71.42% of the medical institutions took measures on the supervision on the continuous service of birth defect prevention and control,as well as implementation of two-way referral. Management evaluation index system on two-way referral system and evaluation index system of birth defect medical service chain management were established in 71.42% of the medical institutions. 57.14% of the staff had a relatively favorable attitude towards providing continuous services provision. 42.86% of the medical institutions provided certain subsidies to the families with financial difficulties.Conclusions Sharing the patient information of pre-marital,pre-pregnancy,prenatal consultation and examination and the rate of clinical reception were the main influencing factors on the continuous service of birth defect prevention. The influencing factors on the continuous service of birth defect prevention could be divided into two aspects.One was the continuous impact on the medical and health information transmission,with the influencing factors of prenatal screening status proportion of projects completed before and during the first trimester of pregnancy for folic acid prevention of neural tube defects,integrity of information transfer between institutions on pre-marital,pre-pregnancy,prenatal consultation and examination,mutual recognition on the medical examination results. The other one was the continuous impact on health service delivery and utilization,with the influencing factors of patient compliance,convenience of visiting doctors,continuous services of the medical care,preventive health care and rehabilitation. Establishing of management evaluation index system on two-way referral system and evaluation index system of birth defect medical service chain management,as well as provision of certain subsidies to the families with financial difficulties were considered the influencing factors of medical service management on continuous service of birth defect prevention.