Abstract: Polycystic ovary syndrome (PCOS) is one of the most common reproductive endocrine disorders. The main features of PCOS include hyperandrogenism, chronic anovulation, polycystic ovaries and insulin resistance. MicroRNAs (miRNAs) are a family of small-molecule, single-stranded, non-coding RNAs, which regulate the expressions of target genes at the posttranscriptional level. MiRNAs can influence follicular development, ovulation and atresia by regulating ovarian granulosa cell proliferation and apoptosis. MiRNAs also cause the endocrine disorder by disturbing the androgen synthesis, and induce insulin resistance through regulating glucose metabolism and insulin sensitivity. It is concluded that miRNAs participate in the pathogenesis of PCOS. In this article, the research progress of miRNAs in etiology of PCOS was reviewed.

Key words: MicroRNAs, Polycystic ovary syndrome, Hyperandrogenism, Insulin resistance, Ovarian follicle, Follicular atresia