Abstract: Objective: Based on the socio-ecological model, this study utilized network analysis to construct a network structure of factors influencing physical activity in pregnant women and identify the core factors. Methods: By convenient sampling method, a total of 602 pregnant women recruited from a tertiary grade A hospital in Guangzhou were investigated with the Sociodemographic and Prenatal Data Questionnaire, Pregnancy Physical Activity Questionnaire and Predictors of Pregnancy Physical Activity Questionnaire from August 2022 to January 2023. Results: The mean energy expenditure on physical activity during pregnancy was (106.68±92.80) MET-h/week. A total of 59.4% of pregnant women did not meet the recommended physical activity standard. According to network analysis, the influencing factors were categorized into three clusters including the individual, interpersonal, and environmental aspects, which were not only interconnected but also mutually influential. Among these factors, the "perceived importance of maternal health during pregnancy" exhibited the highest strength, closeness, and betweenness degree. Conclusion: More than half of pregnant women are physical inactive, and the perceived importance of maternal health during pregnancy is central to the network of influencing factors. Healthcare providers should develop physical activity promotion programs targeting at pregnant women from diverse perspectives of individual, interpersonal, and environmental factors, with an emphasis on enhancing the perceived importance of maternal health during pregnancy.

Key words: socio-ecological model; pregnant women; physical activity; influencing factors; network analysis