Figure 3.

Working model for excess androgen action on follicle and stroma in PCOS. In PCOS, the disturbed balance between androgens, AMH and FSH leads to antral follicular arrest. Circulating FSH-levels are insufficient to reach the increased FSH-threshold of the follicles and selection for dominance does not occur. The hypervascular, rigid and inflammatory cortex negatively impacts the follicular dynamics. Exaggerated blood supply, partly mediated by local androgen overproduction, fuels the whole process. The blue ovals indicate follicles, red circles blood vessels, yellow squares inflammatory cells and green bowed lines stand for connective tissue.