IL6 and polycystic ovary syndrome: The total difference became statistically significance since added the study by Sammy et al. [15] (SMD = 0.51, 95% CI = 0.02–1.01), and the tendency of SMD remained stably since 2012 (0.79 to 0.92), which provided further evidence for differences in the IL-6 levels of the PCOS patients over time compared to the controls.