OBJECTIVE: To determine whether self-selected women with polycystic ovary syndrome (PCOS) are abnormal compared with a control population. DESIGN: Case-control. SETTING: Support group meeting organized and initiated by patients. PATIENT(S): Forty-five self-selected women with PCOS and 80 control women. INTERVENTION(S): Self-selected women with PCOS at a peer support conference completed a questionnaire, had a brief physical, and gave a fasting blood sample. MAIN OUTCOME MEASURE(S): Historical, biometric, and assay results. RESULT(S): Sixty percent of the women attending the conference participated in the study. Most had been diagnosed with PCOS on the basis of ovarian morphology (35%). They were more likely to be nulliparous and have a history of oligomenorrhea (96%). They were hyperandrogenemic (significantly elevated testosterone and DHEAS levels) compared with control women. Self-selected women with PCOS displayed multiple metabolic abnormalities compared with control women, including elevations in blood pressure, waist-hip ratio, fasting insulin, fasting total cholesterol, and fasting low-density lipoprotein cholesterol levels, as well as a significant decrease in fasting glucose-insulin ratio and high-density lipoprotein cholesterol levels. CONCLUSION(S): Self-selected women with PCOS have reproductive and metabolic abnormalities. The majority of these women received inadequate treatment despite having risk factors for endometrial cancer, diabetes, and/or heart disease. Our study also suggests that women attending or participating in a PCOS support group are willing and likely to participate in clinical studies.