Objective: To evaluate the prevalence of chronic endometritis (CE) in women with unexplained infertility compared to healthy controls, with diagnostic assessments conducted during the embryo implantation window.
Design: Prospective observational cohort study.
Setting: University hospital.
Patient(s): Women with unexplained infertility and healthy controls.
Intervention(s): Endometrial biopsies were obtained during the implantation window and analyzed using immunohistochemical staining for syndecan-1 (CD138) to identify plasma cell infiltration.
Main outcome measure(s): Prevalence of CE, as determined by hysteroscopic features, conventional histology, and immunohistochemical staining.
Results: CE was more frequently identified in women with unexplained infertility than in healthy controls. Immunohistochemical analysis detected plasma cell infiltration in 40.63% of infertile women and 23.08% of controls. Hysteroscopic findings suggestive of CE were observed in 53.12% of infertile women, showing a sensitivity of 68.75% and a negative predictive value of 80.76%. Diagnostic concordance between hysteroscopic evaluation and immunohistochemistry was 71.1%.
Conclusion: CE may be more prevalent among women with unexplained infertility during the embryo implantation window. Although hysteroscopy-directed biopsy combined with immunohistochemical analysis may improve diagnostic accuracy, further studies are needed to compare different biopsy techniques and assess potential impact on fertility outcomes.
Keywords: CD138 cells; Embryo implantation; Endometrial biopsy; Reproductive health; Unexplained infertility.
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