This proangiogenic milieu is reinforced by reduced concentrations of antiangiogenic factors, such as adiponectin [65] and interferon-gamma-induced protein 10 (IP-10) [66, 67], although levels of the endogenous VEGF antagonist soluble Flt-1 were reported to be increased in the pelvic fluid of endometriosis cases [68]. Here, FLT1 is linked to endometriosis.