The therapeutic effects and mechanisms of action of resveratrol on polycystic ovary syndrome: A comprehensive systematic review of clinical, animal and in vitro studies.

Polycystic ovary syndrome (PCOS) is one of the most important and common polygenic endocrine disorders among women of reproductive age. Resveratrol, a natural phenol, is involved in various biological activities, including antioxidant, antiseptic, anti-inflammatory, anti-ageing and anti-cancer effects. This systematic review aimed to investigate the therapeutic effects and mechanisms of actions of resveratrol in PCOS. The present study was conducted according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis statements. We searched PubMed, Science Direct, Google Scholar, Scopus, ISI Web of Science, ProQuest and Embase databases up to August 2021 by using the relative keywords. Original studies published in the English language that assessed the effects of resveratrol on PCOS and its associated complications were considered. Out of 417 records screened, only 24 articles met the inclusion criteria: 10 in vitro, 10 animal and 4 human studies. The results obtained in the present study showed that resveratrol supplementation might be effective in improving PCOS-related symptoms by reducing insulin resistance, alleviating dyslipidaemia, improving ovarian morphology and anthropometric indices, regulating the reproductive hormones and reducing inflammation and oxidative stress by affecting biological pathways. According to the available evidence, resveratrol may reduce the complications of PCOS. However, further studies are recommended for a comprehensive conclusion on the exact mechanism of resveratrol in PCOS patients.