CXCR4 and hydrops fetalis: A total of 15 AR-DEGs of HF were obtained by intersecting 241 up-regulated genes and 201 down-regulated genes with 803 ARGs, of which 6 up-regulated (SNCA, PLCE1, MAPK10, CXCL12, TPCN1, CXCR4) and 9 down-regulated (S1PR3, MAP2K1, NAMPT, S100A9, CD38, S100A8, CYBB, CCL2, SPP1), and the Venn diagram is shown in Figure 3A.