Distinct Suppression of Prednisone on Endometrial Immune Cells in Women With Reproductive Failure

Research Question For women with reproductive failure, prednisone is widely used but remains controversial as a therapy for improving clinical outcomes. This study aimed to investigate the impact of prednisone on various endometrial immune cells. Design A total of 24 women with repeated implantation failure and recurrent miscarriage underwent their first endometrial biopsy precisely 7 days after luteinizing hormone surge (LH surge +7). Prednisone was administered from the first day of the subsequent menstrual cycle, followed by the second endometrial sampling on day LH surge +7 again. The density and cell–cell clustering of CD3−CD56+CD16− NK cells, CD3−CD56+CD16+ NK cells, CD68+CD16− macrophages, CD68+CD16+ macrophages, CD3+CD56− T cells, and CD3+CD56+ NK‐T cells were analyzed by multiplex staining and compared before and after prednisone treatment. Results Following prednisone treatment, a significant decrease in the percentage of CD3−CD56+CD16− NK cells ( p < 0.001), CD68+CD16− macrophages ( p = 0.007), and their clustering degree ( p = 0.038) was observed. No significant changes were noted in CD3−CD56+CD16+ NK cells, CD68+CD16+ macrophages, CD3+CD56− T cells, CD3+CD56+ NK‐T cells, and their cell–cell clustering. Conclusion Prednisone does not generally reduce all endometrial immune cells; instead, it selectively suppresses specific immune cell subtypes in women with reproductive failure.