Is there a link between obesity and PCOS? 

There is an association of PCOS with obesity, although not universal, nor necessary nor sufficient for the PCOS phenotype. Obesity, particularly visceral adiposity which is common in obese and non-obese women with PCOS, amplifies and worsens all metabolic and reproductive outcomes in PCOS. Obesity increases insulin resistance and compensatory hyperinsulinemia, which in turn increases the production of fatty tissue and decreases the destruction of fat.

Obesity sensitizes thecal cells of the ovary to LH stimulation and amplifies hyperandrogenism (excessive androgens in blood) by upregulating ovarian androgen production. Obesity increases inflammatory adipokines which, in turn, increase insulin resistance and adipogenesis (prouction of fatty tissue).

Lifestyle interventions focused on diet-weight loss and concurrent exercise are central to therapy which also commonly subsequently needs to include pharmacologic therapy. PCO symptoms commonly improve with 5% to 10% weight loss, but 25% to 50% wieght loss, usually achievable only through bariatric surgery, may be reuired for morbid obesity (BMI >40kg/m²) unresponsive to lifestyle-medical treatment. 

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