BACKGROUND For a number of reasons, the results of previous meta-analyses may not fully reflect the mental health status of the average woman suffering from polycystic ovary syndrome (PCOS), or the causes of this distress. Our objective was to examine emotional distress and its associated features in women with PCOS. METHODS A comprehensive meta-analysis of comparative studies reporting measures of depression, anxiety or emotional-subscales of quality of life (emoQoL) was performed. PubMed, Embase, PsychInfo and the Cochrane trial register databases were searched up to November 2011 (see Supplementary Data for PUBMED search string). Unpublished data obtained through contact with authors were also included. The standardized mean difference (SMD) of distress scores was calculated. Subgroup analyses and meta-regression analysis of methodological and PCOS-related features were performed. RESULTS Twenty-eight studies (2384 patients and 2705 control women) were included. Higher emotional distress was consistently found for women with PCOS compared with control populations [main outcomes: depression: 26 studies, SMD 0.60 (95% confidence interval (CI) 0.47-0.73), anxiety: 17 studies, SMD of 0.49 (95% CI 0.36-0.63), emoQoL: 8 studies, SMD -0.66 (95% CI -0.92 to -0.41)]. However, heterogeneity was present (I(2) 52-76%). Methodological and clinical aspects only partly explained effect size variation. CONCLUSIONS Women with PCOS exhibit significantly more emotional distress compared with women without PCOS. However, distress scores mostly remain within the normal range. The cause of emotional distress could only partly be explained by methodological or clinical features. Clinicians should be aware of the emotional aspects of PCOS, discuss these with patients and refer for appropriate support where necessary and in accordance with patient preference.