Additionally, PCOS endometrial stromal fibroblasts produce higher levels of IL-6, IL-8, MCP-1, and granulocyte-macrophage colony-stimulating factor (GM-CSF), which facilitate the maturation of endometrial DCs and macrophages, subsequently leading to progesterone resistance in the endometrium and impairing endometrial decidualization (57). This evidence concerns the gene CSF2 and polycystic ovary syndrome.