Definition:
Polycystic Ovarian Syndrome (PCOS) is a reproductive disorder characterised by multiple cystic growths on the ovaries.
PCOS develops when the ovaries are stimulated to produce excessive amounts of male hormones (androgens), particularly testosterone, either through the release of excessive luteinising hormone (LH) by the pituitary gland or through high levels
of insulin in the blood (hyperinsulinaemia) in women whose ovaries are sensitive to this stimulus.
PCOS is characterised by a complex set of symptoms with research to date suggesting that insulin resistance is a leading cause.
A majority of patients with PCOS (some investigators say all) have insulin resistance. Insulin resistance is a common finding among both normal weight and over weight PCOS patients. Their elevated insulin levels contribute to or cause the abnormalities seen in the hypothalamic-pituitary-ovarian axis that lead to PCOS. Specifically, hyperinsulinaemia causes a number of endocrinological changes associated with PCOS, including the following:
* Increased GnRH pulse frequency.
* LH over FSH dominance.
* Increased ovarian androgen production.
* Decreased follicular maturation.
* Decreased SHBG binding.
PCOS is the most common cause of oligomenorrhoea and amenorrhoea , although 20-25% of normally menstruating women have PCOS. These women may have reduced fertility and an increased risk of miscarriage.

Aetiology/Major causative factors and risk factors that can contribute to the incidence of PCOS include:
* insulin resistance
* obesity
* family history of PCOS
* stress
* nutritional deficiencies
* high glycaemic load diet
* sedentary lifestyle
 
Common signs and symptoms of PCOS include:
* Irregular menstrual cycles–i.e., oligomenorrhoea or amenorrhoea
* Infertility, generally resulting from chronic anovulation (lack of ovulation)
* Elevated serum (blood) levels of androgens (male hormones), specifically testosterone, androstenedione, and dehydroepiandrosterone sulphate (DHEAS), causing hirsutism and occasionally masculinisation.
* Central obesity–"apple-shaped" obesity centred around the lower half of the torso
* Androgenic alopecia (male-pattern baldness)
* Acne , oily skin, seborrhoea
* Acanthosis nigricans
* Prolonged periods of PMS-like symptoms
* Sleep apnoea
* Multiple cysts on the ovaries
* Enlarged ovaries, generally 2-3 times larger than normal, resulting from multiple cysts
* Chronic pelvic pain
* BGL dysregulation –e.g., hypoglycaemic episodes, diabetes, etc
* Hypothyroidism