**3. Obesity**

Obesity is present in 30–60% of patients with PCOS with body mass index (BMI) greater than 30 kg/m<sup>2</sup> and is often associated with a state of hyperinsulinism. However, even in this case, the cutoff choice can be discussed and modified on the basis of geographical and socioeconomic considerations. The presence of obesity in women with PCOS results in worsening in the metabolic and reproductive outcomes [9].

Obese women with PCOS compared to women with normal weight with PCOS have increased prevalence of glucose intolerance and type 2 diabetes mellitus [10], higher prevalence of hirsutism [11], greater risk of metabolic syndrome, and therefore cardiovascular disease [12, 13]. Obesity increases the prevalence of obstructive sleep apnea in patients with PCOS [14].

A lipolysis dysregulation in PCOS patients has been documented [15], as an increased lipolysis of visceral fat resulting in an increase in free fatty acids released directly into the portal circulation. The free fatty acid levels in the hepatic portal circulation are the major modulators of hepatic gluconeogenesis [16]. This increased visceral fat lipolysis may be one of the mechanisms for increased risk of glucose intolerance [17].

In obese women with PCOS, physical activity and low-calorie diet intake lead to an improvement in ovarian function and reduction of the risk of type 2 diabetes mellitus [18]. Exercise and weight control are highly recommended because of their direct effect not only on the metabolic framework but also on ovarian function and restoration of fertility [19]. Success in treating obesity requires a multidisciplinary approach involving the dietician, the psychologist, and the physician.
