Figure 1 Schematic diagram of estrogen and progesterone level fluctuations during the menstrual cycle and flowchart of the preparation process for a rat model of abnormal uterine bleeding
Note： Curves in the figure represent the changes in estrogen and progesterone levels during the normal human menstrual cycle. The process in the figure illustrates the protocol for preparing a rat model of abnormal uterine bleeding.

Figure 2 Detection of changes in the estrous cycle in abnormal uterine bleeding model rats using vaginal exfoliated cell smear （methylene blue staining， ×200）
Note： A， Morphological changes of vaginal exfoliated cells of a representative rat in the normal control group during one estrous cycle （Days 1， 2， 3， and 4 correspond to proestrus， estrus， metestrus， and diestrus， respectively， showing cyclical changes）； B， Morphological changes of vaginal exfoliated cells of a representative rat in the model group from ovariectomy， hormone induction to progesterone withdrawal （Days 1， 2， 3， and 4 correspond to diestrus， proestrus， estrus， and estrus， respectively， showing a non-cyclic pattern）. In figures， black arrows （?） indicate nucleated epithelial cells， asterisks （*） mark keratinized epithelial cells， and boxes （□） denote white blood cells. In figures， the scale bar is 50 μm.

Figure 3 Uterine morphology， bleeding patterns， and histopathological changes of endometrial tissues in abnormal uterine bleeding model rats
Note： A， Uterine morphology and the HE-stained images of endometrial tissue in normal control rats； B-F， The uterine morphology in AUB model rats at 0 h， 12 h， 24 h， 36 h， and 48 h after progesterone withdrawal， along with vaginal cotton balls collected for uterine bleeding assessment every 12 hours （lower right corner）， and the HE-stained images of endometrial tissue at the corresponding time points. The two asterisks （*） in each low-magnification HE-stained image indicate the two areas observed under high magnification， and the black arrows （?） point to the structures and pathological phenomena such as the endometrial epithelium， glands， necrotic stroma， blood vessels， and bleeding. In the HE-stained images， the scale bars from left to right column are 500 μm， 50 μm and 50 μm， respectively.

Figure 4 Changes in serum sex hormone levels， injury and repair of uterus blood vessels and stroma， and vascular contractile function of uterus in abnormal uterine bleeding model rats
Note： A， ELISA was used to measure serum levels of sex hormones， including FSH， E₂， LH， and PROG， in normal control rats and the AUB model rats at 36 h after progesterone withdrawal （n=6）. B， Immunohistochemistry was performed to assess the expression of vascular endothelial marker platelet endothelial cell adhesion molecule-1 （CD31）， angiogenesis-related protein vascular endothelial growth factor （VEGF）， and stromal injury/repair protein matrix metalloproteinase-9 （MMP-9） in uterine tissues of both groups，along with statistical analysis of the results （n=3； scale bars： 100 μm）. Additionally， TUNEL staining of rat endometrium was conducted， and the percentage of positive cells was quantified ［n=3； asterisks （*） in low-magnification images （scale bars： 100 μm） indicate regions selected for high-magnification observation （scale bars： 25 μm）］. C， Western blotting was employed to detect the expression of fibroblast growth factor 2 （FGF2） and endothelin-1 （ET-1） in uterine tissues of both groups， along with relative quantification （n=3； data presented as mean ± standard error （SE）； Compared with normal control group， ^nsP＞0.05， ^*P<0.05， ^**P<0.01）.

Figure 5 Transcriptomic analysis of differentially expressed genes in uterine tissue of abnormal uterine bleedingmodel rats
Note： A， The number of genes in rat samples from the normal control rats and the AUB model rats at 36 h after progesterone withdrawal （Model-36 h）（compared with normal control group， ^****P<0.000 1）； B， Results of principal component analysis； C， Venn diagram showing the differences in expressed genes between the two groups ［The blue area represents the gene set with significantly decreased expression （Down） in the Model-36 h compared to normal control group， while the red area represents the gene set with significantly increased expression （Up） in the Model-36 h compared to normal control group］； D， Volcano plot of differentially expressed genes （down-regulated differentially expressed genes meeting fold change criteria in blue， non-meeting fold change criteria in light blue； up-regulated differentially expressed genes meeting criteria in red， non-meeting criteria in light red； non-significantly expressed genes in gray. The plot labels some of the differentially expressed genes with higher fold changes， including both down-regulated and up-regulated ones）； E， Differentially expressed gene clustering heatmap by group， where the intensity of color represents the value of data points （grouping and clustering are based on similarity， and genes with higher fold changes in up-regulation and down-regulation are labeled in the heatmap）.

Figure 6 Transcriptomic analysis of differentially expressed genes in uterine tissue of model rats with abnormal uterine bleeding
Note： A， GO functional analysis of up-regulated differentially expressed genes； B， GO functional analysis of down-regulated differentially expressed genes； C， KEGG enrichment analysis of up-regulated differentially expressed genes； D， KEGG enrichment analysis of down-regulated differentially expressed genes.