The differential sperm miRNA expression in partners of women with unexplained recurrent miscarriage

This study aimed to profile differential sperm miRNA expression in partners of women with unexplained recurrent miscarriage, and explore its association with unexplained recurrent miscarriage.Sperm miRNAs were profiled via high-throughput sequencing, followed by RT-qPCR validation of 3 paternal miRNAs in embryos. GO and KEGG enrichment analyses were performed for target genes of key candidate hsa-miR-34c-5p. We identified 90 differentially expressed miRNAs in case group sperm, 4 of which were paternal miRNAs in embryos. RT-qPCR confirmed significant downregulation of sperm hsa-miR-34c-5p in cases (p=0.001). Its target genes were enriched in cellular membrane components, nervous system-related processes, Notch and Rap1 signaling pathways. This study reveals the association between low sperm miR-34c-5p expression and unexplained recurrent miscarriage, further advancing our understanding of sperm-derived small RNAs in regulating embryonic development and pregnancy outcomes.