Evaluating the medical literature in reproductive medicine: questions concerning prognosis

To illustrate the recommended approach to questions concerning prognosis and the formulation of clinical recommendations, the principles of evidence-based medicine were applied to questions regarding the cardiovascular health risks associated with polycystic ovary syndrome (PCOS) and the effects of treatment on risk. A critical examination of the published literature reveals that the clinical diagnosis of PCOS does not, by itself, increase the risk of developing coronary heart disease (CHD) or adversely affect the prognosis in women with CHD. Rather, any increased risks can be attributed to other known risk factors (obesity, hypertension, diabetes, dyslipidemia) commonly observed in women with the disorder. Treatment strategies that decrease the probability of developing such co-morbid conditions (diet, exercise) or are effective in their management (antihypertensives, statins, insulin-sinsitizing agents) may be expected to reduce risk or improve prognosis, but available evidence is insufficient to warrant a general recommendation for metformin treatment as a CHD risk reduction strategy in all women with PCOS.