Effect of cinnamon on polycystic ovary syndrome (PCOS): A Systematic Review

The effectiveness of various medicinal plants on clinical and non-clinical symptoms of PCOS has been investigated. This study was performed with aim to determine the efficacy of cinnamon on PCOS in a systematic review.

In this systematic review study, the studies were searched in the Iranian and international databases of PubMed, Scopus, Web of science, Cochrane library, Magiran, SID, and IranDoc in February 2020. The terms of "polycystic ovary syndrome", "cinnamon" and "medicinal plant" were used for the searching process. In this study, a variety of experimental and semi-experimental human and animal studies with aim to evaluate the effect of cinnamon on PCOS were entered to the study.

In this systematic review study, 588 articles were reviewed, and finally, eight original human research articles, 1 article as an article presented in the congress, and 3 animal articles had the inclusion criteria. In terms of primary outcome, one study had reported a significant improvement in the frequency of menstrual cycles (improvement in oligomenorrhea status), six studies had reported a significant improvement in metabolic indicators, and one study had reported a decrease in Anti-mullerian hormone levels. Animal studies had reported improvement in metabolic indicators, hormonal levels, and follicle maturation.

The majority of human and animal studies indicated that cinnamon consumption can be useful in improving metabolic indicators and some clinical symptoms in patients with PCOS. Therefore, more clinical trial studies are recommended to be performed for determining its efficacy and dose.