Polycystic ovarian syndrome or PCOS is the most common hormonal abnormality in this population, affecting about 4–18% of reproductive-age women.  Signs and symptoms can range in severity from increased androgen production (male hormones) and altered gonadotropin secretion. These hormones can force its sufferers to deal with irregular or prolonged periods, excess body and facial hair (hirsutism), acne, and male-pattern baldness. Nothing a girl wants! Not surprisingly, these symptoms lead to increased anxiety and depression among women and even adolescents.    Still, even more devastating to some PCOS patients is the possibility of infertility and increased risk of endometrial cancer.   
If that wasn’t enough, PCOS also has metabolic characteristics leading to even more health problems, including increased risk of insulin resistance, type 2 diabetes, fatty liver disease, dyslipidemia, a prothrombotic state, and cardiovascular disease.   As you might have guessed, PCOS is strongly associated with obesity, with prevalence of 80% amongst patients in the United States. 
Doctors use one of three sets of criteria to diagnose patients with PCOS :
Once diagnosed, treatments vary based on individual preferences and desired fertility. Multiple pharmaceutical options are available to address specific comorbidities of PCOS, including oral contraceptives, Metformin (Glucophage), Clomiphene, Inositol, and Spironolactone. But before medication is prescribed, a crucial part of management is exercise and diet.
The exact cause of PCOS is still unclear, but we know there’s a substantial connection to excess weight, insulin resistance, and metabolic syndrome.   Insulin resistance and hyperinsulinemia appear to be linked to PCOS independent of obesity. High blood levels of insulin can increase hormone stimulation in the ovaries as well as act on reproductive hormones in the brain and adrenal glands.  So, it would be intuitive to make dietary changes to decrease insulin levels, naturally restore insulin sensitivity, and reverse metabolic syndrome while reducing weight. This is where the ketogenic diet shines!
Studies have shown that even without weight loss, compared to a standard diet, reducing carbohydrates in PCOS patients led to decreased fasting insulin levels, fasting glucose levels, insulin resistance, total testosterone, and cholesterol.   Additional studies have demonstrated similar findings, in addition to weight loss, that further substantiate the benefits of a low-carbohydrate diet.  Specifically, the ketogenic diet has shown significant improvement in weight, reproductive hormone levels, and fasting insulin levels in women with obesity and PCOS. 
It is evident that a ketogenic diet will reduce insulin levels and body weight, which will in turn reduce or improve symptoms of PCOS. As always, discuss with your doctor before discontinuing any medications or dietary interventions. Check out ketogenic.com’s list of keto-friendly doctors!