Regulatory Roles of MicroRNAs in Female and Male Human Reproduction: A Narrative Review.

The role of microRNAs (miRNAs) in human reproduction represents an area of research, as these regulatory molecules appear to play essential roles in reproductive function. However, the current understanding of miRNAs' regulatory mechanisms in male and female reproduction remains incomplete, with considerable contradictory evidence in the literature. This targeted review aimed to analyze high-quality studies published to date on miRNA expression patterns in female and male reproduction to elucidate their biological roles and associations with infertility, thereby updating knowledge in this field. A comprehensive review of the literature was conducted using different electronic databases and search engines, including PubMed Central, MEDLINE, and Google Scholar from the earliest available records up to 2023. This search identified 18,100 articles related to miRNA expression in infertility, polycystic ovary syndrome (PCOS), endometriosis, and biomarkers, of which 72 met our criteria for further analysis. The findings of the present study revealed that specific, stable miRNA populations exist in different tissues and cells, potentially influencing spermatogenesis and oogenesis. The extensive review of studies suggested a consistent relationship between aberrant miRNA expression patterns and infertility. Consequently, the miRNAs identified in this review might serve as valuable biomarkers for both male and female infertility and could lead to the development of novel and specialized treatments. This manuscript has been released as a preprint at Authorea: (https://doi.org/10.22541/au.169609839.97787658/v1).