A systematic review and meta-analysis of fatty acid composition in polycystic ovary syndrome: perspectives from blood and follicular fluid

A comprehensive assessment of fatty acids (FAs) in polycystic ovary syndrome (PCOS) has yet to be carried out. The current study aimed to synthesize existing evidence on the FA composition of blood and follicular fluid (FF) in women with PCOS compared to non-PCOS controls. Four electronic databases were systematically searched until February 2025 using standard keywords. Risk of bias and evidence certainty were assessed using the ROBINS-I framework and the GRADE system, respectively. Random effects models were employed to calculate pooled standardized mean differences (SMDs) with respective 95% confidence intervals (CIs). Publication bias was inspected using funnel plots, Begg’s test, and Egger’s test. Twelve studies qualified for inclusion in the meta-analysis. Overall effect sizes for several prominent FAs, including palmitoleic acid (SMD [95% CI] = 0.389 [0.121, 0.657], p = 0.004, I 2 = 25.2%), oleic acid (SMD [95% CI] = 0.811 [0.107, 1.515], p = 0.024, I 2 = 90.0%), linoleic acid (SMD [95% CI] = 0.542 [0.349, 0.736], p < 0.001, I 2 = 0%), and arachidonic acid (SMD [95% CI] = 0.252 [0.053, 0.451], p = 0.013, I 2 = 0%), indicated an increase in the PCOS group. The direction and significance of the results partly persisted following subgroup analyses based on sample type and lipid fraction, as well as sensitivity analyses. The findings of this study suggest that FA profile may be altered in women with PCOS, primarily characterized by potential elevations in levels of key mono- and n-6 polyunsaturated FAs.