What is Polycystic Ovary Syndrome (PCOS)?

Polycystic Ovary Syndrome (PCOS): Definition, Diagnosis, and Management

Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting 4-6% of reproductive-age women, characterized by hyperandrogenic chronic anovulation, menstrual irregularities, and polycystic ovarian morphology, which can lead to significant reproductive, metabolic, and psychological complications. 1

Definition and Pathophysiology

PCOS is a heterogeneous condition with complex pathophysiology involving:

• Acceleration of pulsatile gonadotropin-releasing hormone (GnRH) secretion leading to hormonal imbalances 1
• Insulin resistance and hyperinsulinemia causing metabolic dysregulation 1
• Hypersecretion of luteinizing hormone (LH) and elevated LH/FSH ratio (>2) 1
• Ovarian theca stromal cell hyperactivity resulting in excess androgen production 1
• Hypofunction of the follicle-stimulating hormone (FSH)-granulosa cell axis causing follicular arrest and ovarian acyclicity 1

Diagnostic Criteria

The Rotterdam criteria are most widely accepted for adult women, requiring two of the following three features:

• Hyperandrogenism (clinical or biochemical) 1
• Oligo- or anovulation 1
• Polycystic ovaries on ultrasound (>10 peripheral cysts, 2-8 mm diameter, with thickened ovarian stroma) 1

For adolescent girls, diagnostic criteria differ and focus on menstrual irregularity, clinical hyperandrogenism, and/or hyperandrogenemia, without requiring ultrasound findings 2.

Clinical Presentation

PCOS manifests with various symptoms including:

• Menstrual irregularities (oligomenorrhea or amenorrhea) 1
• Hyperandrogenism signs:
  • Hirsutism (excess facial and body hair) 1, 3
  • Acne 3, 2
  • Androgenic alopecia 3
• Infertility due to chronic anovulation 3, 4
• Metabolic features:
  • Obesity (particularly abdominal) 1
  • Insulin resistance 1
  • Acanthosis nigricans (darkened, velvety skin patches) 1

Differential Diagnosis

Several conditions must be excluded before confirming PCOS diagnosis:

• Cushing's syndrome 1
• Androgen-secreting tumors of the ovary or adrenal gland 1
• Nonclassic (late-onset) congenital adrenal hyperplasia 1
• Thyroid disorders 1
• Hyperprolactinemia 1
• Primary hypothalamic amenorrhea 1
• Primary ovarian failure 1

Laboratory and Imaging Evaluation

Key diagnostic tests include:

• Hormonal assessment:
  • LH and FSH levels (days 3-6 of cycle) 1
  • Testosterone (>2.5 nmol/L suggests PCOS) 1
  • Androstenedione (>10.0 nmol/L requires ruling out tumors) 1
  • Progesterone (mid-luteal phase, <6 nmol/L indicates anovulation) 1
• Metabolic assessment:
  • Fasting glucose and insulin (glucose/insulin ratio >4 suggests insulin resistance) 1
  • Lipid profile (total cholesterol, LDL, HDL, triglycerides) 1
• Transvaginal or transabdominal ultrasound (days 3-9 of cycle) 1

Associated Health Risks

PCOS increases risk for several long-term health complications:

• Type 2 diabetes (requires screening with fasting glucose and 2-hour glucose tolerance test) 1
• Cardiovascular disease due to dyslipidemia and insulin resistance 1
• Endometrial cancer related to chronic anovulation and unopposed estrogen 1
• Psychological disorders including anxiety and depression 1, 5

Management Approaches

Treatment should target specific symptoms and associated health risks:

• Lifestyle modifications (first-line approach):

  • Weight loss through dietary changes for overweight/obese patients 1, 5
  • Regular physical activity 5, 6
  • Stress reduction and sleep quality improvement 5

• Pharmacological interventions:

  • Combined oral contraceptive pills for menstrual regulation and hyperandrogenism 1
  • Metformin for insulin resistance and metabolic features 1, 3
  • Spironolactone for hirsutism and acne 2
  • Progestins (e.g., medroxyprogesterone acetate) to prevent endometrial hyperplasia 1

• For infertility:

  • Weight loss as first-line for overweight women 3
  • Ovulation induction with clomiphene citrate 3
  • Metformin as adjunct therapy 3, 2

Important Considerations

• PCOS should not be confused with isolated polycystic ovaries, which occur in 17-22% of women without symptoms or hormonal abnormalities 1
• Women with PCOS should be regularly screened for cardiovascular risk factors and diabetes 1
• Early diagnosis and intervention may prevent long-term complications and improve quality of life 2
• Treatment should address both reproductive and metabolic aspects of the syndrome 1, 5