A comparison of the prevalence of chronic endometritis determined by the use of different diagnostic methods in women with and without reproductive failure
49 Objective: To compare the prevalence of chronic endometritis (CE) when different 50 diagnostic methods are used. 51 Design: Prospective observational study. 52 Setting: University affiliated hospital. 53 Patient(s) Four groups of women were studied, including women with proven fertility 54 (Fertile, n=40) unexplained recurrent miscarriage (RM, n=93) recurrent implantation failure 55 (RIF, n=39) and infertile subjects undergoing endometrial scratch in a natural cycle preceding 56 frozen thawed embryo transfer (Infertility, n=48) 57 Intervention(s) Endometrial biopsy was performed precisely seven days following LH 58 surge (LH+7) Plasma cells were identified by traditional H&E staining and 59 immunohistochemistry (IHC) for Syndecan 1(CD138) 60 Main Outcome Measure(s) The prevalence of chronic endometritis. 61 Result(s) The use of CD138 epitope is more sensitive than H&E staining in identifying 62 plasma cells. The use of plasma cell count per unit area had the lowest observer variability 63 than that of cell count per 10 randomly chosen HPF or cell count per section. Using this 64 method, the prevalence of CE in women with RM, RIF and Infertility were 10.8% 7.7% and 65 10.4% respectively, not significantly higher than that of fertile subjects (5.0% 66 Conclusion(s) Using what may be a new method of plasma cell assessment, it appears that 67 the prevalence rates of CE reported in many earlier studies may have been over estimated. 68 Chinese Clinical Trials Registry Number: ChiCTR IOC 16007882 69 5