Objective To understand the status quo, characteristics, research hotspots and evolution of international physical activity during pregnancy.
 Methods Search all relevant literature between the data records and June 30, 2018 with the “Pregnancy Exercise” and “Physical Activity During Pregnancy” keywords in the Web of Science core database. According to the basic principles of bibliometrics, based on keyword co-occurrence, citation analysis, co-citation analysis and other measurement methods, the knowledge map is drawn by VOS viewer 1.68 software, and the external features and hotspots of international physical activity research during pregnancy are presented through visual maps.
 Results (1) The study of physical activity during pregnancy started earlier, 30 years ago, and culminated 20 years ago; the subject areas are broad, including: obstetrics, gynaecology, etiology, epidemiology and nutrition, sports science Behind; the journal "American Journal of Obstetrics and Gynecology" ranked first, "Obstetrics and Gynecology" second, "Medicine and Science In Sports and Exercise" third; the core authors work closely; Harvard University, North Carolina The University of Adelaide and the University of Adelaide have made outstanding contributions, and universities have become the main force in this field of research. (2) The hotspots of international physical activity research during pregnancy are mainly distributed in six major areas: 1 the impact of physical activity during pregnancy on maternal health and the risk of complications; 2 the relationship between physical activity and pregnancy outcome during pregnancy; 3 the physical activity of pregnant women during pregnancy and fetal development and Long-term health effects of offspring; 4 factors influencing physical activity during pregnancy; 5 recommended criteria for physical activity during pregnancy, appropriate exercise and exercise during pregnancy, safety and precautions during exercise and exercise; 6 scientific measurement of physical activity during pregnancy Evaluation. (3) In the past 30 years, the research on physical activity and health promotion in the international pregnancy has been increasing year by year. The research hotspots have always evolved around the main line of “physical activity”, “pregnancy”, “fetus”, “health” and “safety”. In addition, its research hotspots also show periodic characteristics that change with the year. Before 1999, the focus of attention was on the “status quo”, “pros and cons” and “safety” of physical activity during pregnancy. In 1999-2006, the focus was on "pregnancy outcomes" and "complications." In 2007-2013, the focus was on “chronic illness” and “exercise prescription”. After 2014, “lifestyle”, “scientific measurement and evaluation” and “epigenetic” gradually became hot spots.
 Conclusions "Physical activity during pregnancy", "sports exercise during pregnancy", "chronic disease", "safety", "pregnancy outcome", "parental fetal health", "measurement and evaluation" will continue to be the main hotspots in the study of physical activity during international pregnancy in the future; The “built environment”, “mental health”, “epigenetic”, “children’s long-term health”, “preferred physical activity recommendation” and “wearable equipment”, “monitoring method” and “regulatory mechanism” embodying health and happiness, people-oriented development strategy "Glucose and lipid metabolism" and so on will also become the focus of research on physical activity during pregnancy in the next period.
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