Objective:To explore the major factor of enhancing monocyte recruitment into the peritoneal cavity. Methods:The stromal cell of ectopic implants was exposed to various concentrations(5,10,20 ng/ml ) of IL-1β and the 10 ng/ml of IL-1β was cocultured with ectopic implants,eutopic and normal endometrium. Concentration of RANTES in the cell culture supernatant was measured with a sandwish ELISA. Results:The 10 ng/ml of IL-1β elicited the highest secretion of RANTES in ectopic implants. The RANTES secreted by the stromal cell of ectopic implants was increased more significantly than that in eutopic and normal endometrium(P < 0.01). After 60 h,the stromal cell of eutopic endometrium secreted much more RANTES than normal endometrium(P < 0.05). Conclusion:These findings are consistent with a feed-forward inflammatory loop among the activate macrophages, RANTES production by ectopic implants and further monocyte chemotaxis. We postulate that this pathway is activated in endometriosis, and the bioactivity of eutopic endometrium was different from normal endometrium.