The Role of the Gut Microbiome in Youth with Polycystic Ovary Syndrome: A Systematic Review.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects women of reproductive age and female adolescents. The diagnosis of PCOS is difficult during puberty due to overlapping of the criteria with normal variations of menstruation during this age period. There are insufficient data on the gut microbiome and PCOS and potential mechanisms linking the two. The present systematic review aimed to detect dysbiosis patterns in youth with PCOS, compared with healthy controls. One hundred seventy-eight studies were identified by a databases search and sixty-eight by a full-text assessment for eligibility; four were included in the systematic review and underwent quality control. The results of the study were controversial in accordance to findings from the literature. A change in gut microbiome α diversity was found in PCOS adolescents, with no significant alterations in β diversity. Almost all studies found Firmicutes, Bacteroidetes, and Actinobacteria in abundance in both groups, with changes in family composition and fluctuations at the phylum level. A statistically significant association between these changes and clinical or biochemical features of the syndrome was described. This systematic review confirmed gut microbiota dysbiosis in youth with PCOS. However, further data are needed to clarify these changes and to build a strategy to prevent the syndrome.