TGFB1 and pelvic organ prolapse: Pelvic organ prolapse is also characterized by the presence of non-significant levels of tissue fibrosis markers such as fibroblast growth factor (FGF), transforming growth factor β (TGF-β), insulin-like growth factor (IGF), and the transmembrane glycoprotein CD44 whose role is to alter the balance between production and degradation of components of the extracellular matrix.