Fig. 1

Comparison of semiquantitative parameters of placental ultrastructures between the GDM group (n = 20) and the control group (n = 20). a-b. The terminal villi of GDM (a) and control (b) placenta. c Placental barrier thickness (arrow) of the GDM group (6746.15 ± 1270.22 nm, n =10) was significantly thicker than that of the control group (4591.34 ± 1178.60 nm, n = 10; P < 0.05), Bar = 5um. d-e The terminal villi of GDM (d) and control (e) placenta. f. The BM of ST in the GDM group (1077.49 ± 194.39 nm nm, n = 10) was thicker than that in the control group (707.54 ± 256.56 nm, n = 10; P < 0.05), Bar = 1um. g-h The density of ST apical microvilli in GDM (g) and control (h) placenta. i The density of ST apical microvilli in the GDM group (44.36 ± 21.95 per 10um, n = 10) was significantly lower than that in the control group (77.13 ± 20.82 per 10um, n =10; P < 0.05), and even microvilli-free in some areas, Bar =2um