The effect of peritoneal fluid from patients with endometriosis on murine sperm-oocyte interaction.

It has been demonstrated that PF contains some factor or factors that interfere with effective gamete interaction as determined by an in vitro animal assay. PF from patients with mild endometriosis has an increased activity of this substance and/or additional inhibitory factors. In endometriosis, this peritoneal fluid factor or factors appear to be filterable and to a significant degree heat-labile. This observation may be of importance in explaining subfertility associated with early stages of endometriosis.