Fig. 10

Timeline view of keyword clusters in preeclampsia research generated using CiteSpace. Each node represents a keyword, with size proportional to its frequency. Clusters are labeled with themes, including #0 “hypertensive disorders of pregnancy,” #1 “invasion,” #2 “blood pressure,” #3”angiogenic factors,” #4 “oxidative stress,” and #5 “antiphospholipid syndrome.” The timeline highlights the temporal evolution of research focus, showing how key themes have emerged and developed over time, with sustained attention on major mechanisms like “oxidative stress” and “angiogenic factors”