Role of Gut Microbiome in Polycystic Ovarian Syndrome and Insulin Resistance

Introduction: Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder among women of reproductive age, often associated with insulin resistance (IR), hyperandrogenism, and ovulatory dysfunction. Recent research highlights a potential link between gut microbiota dysbiosis and the metabolic disturbances seen in PCOS. This review aims to explore the role of gut microbiome composition and function in the pathophysiology of insulin resistance among PCOS patients. Methods: A comprehensive literature review was conducted using PubMed, Scopus, and Google Scholar. Studies included were observational or clinical in design, published in English between 2011 and 2022, and investigated the gut microbiome in women diagnosed with PCOS in relation to insulin resistance. Data extracted included microbiome assessment methods, key microbial taxa, insulin resistance indicators (e.g., HOMA-IR), and therapeutic interventions. Results: Women with PCOS exhibit reduced microbial diversity, characterized by lower levels of SCFA-producing bacteria (e.g., Faecalibacterium prausnitzii) and elevated pro-inflammatory species (e.g., Bacteroides, Enterococcus). These alterations contribute to increased gut permeability, systemic inflammation, and impaired insulin signaling. Clinical interventions using probiotics, prebiotics, and dietary modifications demonstrated improvements in insulin sensitivity and hormonal profiles in several studies. Discussion: Gut microbiota play a significant role in modulating metabolic and endocrine functions in PCOS. Short-chain fatty acids (SCFAs) produced by beneficial bacteria enhance insulin sensitivity, while dysbiosis exacerbates IR through inflammatory pathways. Emerging treatments like fecal microbiota transplantation and personalized nutrition offer promising directions but require further validation. Conclusion: The gut microbiome emerges as a key modulator of insulin resistance in PCOS. Targeted interventions, such as SCFA-enhancing diets, probiotic supplementation, and microbiota-focused therapies—may offer innovative, non-hormonal strategies to manage PCOS. Longitudinal and interventional studies are essential to confirm causality and establish microbiome-based precision treatments.