Variation in diagnostic methods, criteria, and treatment for chronic endometritis: A nationwide survey in Japan.

Aim: To investigate variation in the diagnosis and treatment of chronic endometritis (CE) at the national level in Japan. Methods: We performed a nationwide survey targeting all assisted reproductive technology (ART) facilities across Japan between 2021 and 2022. Diagnostic methods, criteria, and first‐ and second‐line treatment protocols for CE were collected via a questionnaire. Results: Among 616 ART facilities, 437 responded to the survey (response rate: 70.9%) of which 339 (77.6%) implemented diagnosis and treatment of CE. In the diagnosis of CE, 214 (63.1%) facilities used CD138 immunohistochemical staining of endometrial tissue, while hysteroscopy was the most frequently used as an adjunct diagnostic method (241 facilities, 71.1%). The most frequent cutoff value of CD138‐positive cells for diagnosing CE was 3–5 cells/20 high‐power fields (50%), but 7.9% (17 facilities) and 5.1% (11 facilities) used cutoff values of 1 and 2 cells, respectively. The most common first‐ and second‐line treatment methods were doxycycline (210 facilities, 61.9%) and ciprofloxacin + metronidazole (164 facilities, 48.0%), respectively. Conclusions: There is considerable variation in the number of CD138‐positive cells used for diagnosing CE. Establishing unified diagnostic criteria and therapeutic methods for CE is essential to provide standardized medicine for CE at the national level. [ABSTRACT FROM AUTHOR]