Xiao L, et al. - In the endometrium of patients with abnormally high-frequency (hyper-) and low-frequency (hypo-) peristalsis, changes in microRNA (miRNA) were investigated in order to ascertain if uterine peristalsis is regulated by miRNAs. A miRNA microarray and RT-qPCR were used to determine changes in miRNA in endometrial tissue; a collagen gel contraction assay was used on co-cultured human endometrial stromal cells (ESCs) to examine the effects of the altered regulation of miRNAs on uterine smooth muscle contraction; western blots and other assays were employed to illustrate the potential mechanisms involved. As per findings, endometrial samples from patients with hypoperistalsis displayed overexpression of miR-29c-3p among several differentially-regulated miRNAs and showed low expression of oxytocin receptor (OXTR). As per bioinformatic analysis and luciferase assays, OXTR represents a target of miR-29c-3p, which reduces its expression. Additionally, researchers observed increased expression of aldo-keto reductase family 1, member C3 (AKR1C3) and increased release of prostaglandin F2 alpha (PGF2α) when miR-29c-3p was downregulated in ESC cultures. Outcomes here suggest that via attenuating expression of OXTR and reducing PGF2α release, miR-29c-3p in endometrial cells regulates uterine contractility.