Peritoneal fluid of patients with endometriosis promotes proliferation of endometrial stromal cells and induces COX-2 expression.

Cell proliferation of endometrial stromal cells treated with peritoneal fluid of women (aged 25 to 43 years) with endometriosis (n = 12) statistically significantly increased compared with the control treatment (peritoneal fluid of women without endometriosis, n = 8). Also, COX-2 gene expression and prostaglandin E(2) production were induced in those cells by increasing COX-2 promoter transcription activity, which could be attenuated by a specific p38MAPK inhibitor, suggesting a role for peritoneal fluid in the etiopathogenesis of endometriosis.