Polycystic Ovary Syndrome

Definition: It is a syndrome of ovarian dysfunction & endocrine problems associated with hyperinsulinemia. According to Rotterdam Consensus, the diagnostic criteria of which include the following:
• Evidence of hyperandrogenism, biochemical or clinical(hirsutism acne & male pattern baldness).
• Ovulatory dysfunction; amenorrhoea;oligomenorrhoea.
• Morphological polycystic ovaries.

Women who have at least two of these criteria are said to have polycystic ovary syndrome. Polycystic ovaries diagnosed by ultra-sound should not be confused with PCOS. The ultrasonic picture of polycystic ovary is the presence of 12 or more follicles measuring 2-9 mm in diameter or increased ovarian volume (>10 cm3) on transvaginal ultrasound. A woman having PCO in the absence of an ovulation disorder or hyperandrogenism (asymptomatic PCO) should not be considered as having PCOS, although she may develop symptoms over time, e.g if she gain weight.
Aetiology:
The exact aetiology is unknown.
• Genetic factor: the syndrome clusters in families, the prevalence in first degree relatives is 5-6 times higher than in the general population.
• Hormonal factors: Hypersecretion of androgens by theca cells lead not only to the cardinal clinical features of the syndrome, hyperandrogenism, but also lead to inhibition of follicular growth with resultant excess of immature follicles. Hypersecretion of LH stimulate excess production of testosterone by the ovary.
Insulin resistance occur in up to 60 % of women with PCOS especially in those with high BMI. The resultant hyperinsulinaemia stimulate LH- induced androgen production from the ovaries. In the liver elevated insulin causes a decreased production of sex-hormone binding globulin increasing the level of free androgen in the circulation.

Diagnosis:
Diagnosis of PCOS can only be made when other aetiologies have been excluded (thyroid dysfunction, congenital adrenal hyperplasia, hyperprolactinaemia, androgen-secreting tumours and Cushing syndrome).

Clinical features:
• Oligomenorrhoea/ amenorrhoea: related to chronic anovulation.
• Hirsutism.
• Subfertility.
• Obesity.
• Recurrent miscarriage.
• Acanthosis nigricance: areas of increased skin pigmentation occur in axillae & other flexures.

Laboratory test:
A raised luteinising hormone/follicle-stimulating hormone ratio is no longer a diagnostic criteria for PCOS owing to its inconsistency. It should be noted that the diagnosis of PCOS can only be made when other aetiologies have been excluded. The recommended baseline screening tests are thyroid function tests, a serum prolactin and a free androgen index (total testosterone divided by sex hormone binding globulin (SHBG) x 100 to give a calculated free testosterone level). In cases of clinical evidence of hyperandrogenism and total testosterone greater than 5 nmol/l, 17-hydroxyprogesterone should be sampled and androgen-secreting tumours excluded. If there is a clinical suspicion of Cushing syndrome, this should be investigated according to local practice.

• Increased LH level
• Elevated LH:FSH ratio is no longer a diagnostic criteria because of its inconsistency
• Elevated testosterone & androstenedione levels
• Decreased sex hormone-binding globulin
• Increased fasting insulin level or impaired glucose tolerance assessed by GTT.
• Increased prolactin level.

Ultrasound: twelve or more subcapsular follicular cysts <10mm in diameter with increased ovarian stroma (ovarian volume >10cm3 ).









Long-term health implications of PCOS:
include the following:
• Increased incidence of multiple pregnancy, gestational diabetes & pregnancy-induced hypertension.
• Increased incidence of type II diabetes mellitus, hypertension & hyperlipidaemia due to insulin resistance & hyperandrogenism respectively.
• Increased incidence of endometrial hyperplasia & endometrial carcinoma due to unopposed estrogen stimulation.