What is Polycystic Ovary Syndrome (PCOS)?

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

Polycystic Ovary Syndrome (PCOS) is the most common endocrine disorder affecting 8-13% of reproductive-aged women, characterized by a combination of oligo/anovulation, hyperandrogenism, and polycystic ovarian morphology, with significant implications for reproductive, metabolic, and psychological health. 1

Definition and Pathophysiology

PCOS is a complex disorder with the following key pathophysiological mechanisms:

• Insulin resistance: Present in 50-70% of women with PCOS regardless of BMI, contributing to hyperandrogenism through effects on the pituitary, liver, and ovaries 1
• Hyperandrogenism: Results from ovarian theca stromal cell hyperactivity and dysregulation of the hypothalamic-pituitary-ovarian axis 1
• Anovulation: Caused by acceleration of pulsatile gonadotropin-releasing hormone (GnRH) secretion and hypofunction of the FSH-granulosa cell axis 1
• Genetic and environmental factors: PCOS is highly heritable with polygenic, multifactorial inheritance patterns 2

Diagnostic Criteria (Rotterdam Criteria)

Diagnosis requires the presence of at least two of the following three criteria:

1. Oligo/anovulation: Manifesting as irregular menstrual cycles, oligomenorrhea, or amenorrhea
2. Hyperandrogenism: Clinical (hirsutism, acne) or biochemical (elevated testosterone levels)
3. Polycystic ovarian morphology: On ultrasound, characterized by:
   • ≥10 peripheral cysts, 2-8 mm in diameter in one ultrasound plane
   • Thickening of ovarian stroma 1

Clinical Manifestations

PCOS presents with various symptoms:

• Reproductive: Irregular menstrual cycles, infertility, pregnancy complications 1
• Dermatologic: Hirsutism, acne, male-pattern hair loss 3
• Metabolic: Weight gain, difficulty losing weight, abdominal obesity 1
• Psychological: Depression, anxiety, poor self-esteem, body image issues, eating disorders 1

Associated Health Risks

Women with PCOS face increased risks for:

• Metabolic disorders: Type 2 diabetes, metabolic syndrome, dyslipidemia 1
• Cardiovascular disease: Increased coronary artery calcium scores, carotid intima-media thickness 4
• Reproductive cancers: At least twofold increased risk of endometrial cancer 3
• Sleep disorders: Higher prevalence of obstructive sleep apnea 3
• Mental health disorders: Depression, anxiety, bipolar disorder 4

Diagnostic Evaluation

Comprehensive evaluation includes:

• Hormonal testing:

  • LH/FSH ratio (>2 suggests PCOS)
  • Testosterone (>2.5 nmol/L)
  • Progesterone (<6 nmol/L in mid-luteal phase indicates anovulation) 1

• Metabolic assessment:

  • Fasting glucose/insulin ratio
  • Lipid profile 1

• Ultrasound: Transvaginal or transabdominal (day 3-9 of cycle) to assess ovarian morphology 1

Management Approach

Treatment should be tailored based on the patient's primary concerns:

1. For Menstrual Irregularities and Hyperandrogenism

• First-line: Combined oral contraceptives to regulate cycles and reduce androgen levels 3
• Second-line: Add anti-androgens (spironolactone, finasteride) for persistent hirsutism 4, 3

2. For Metabolic Complications

• First-line: Lifestyle modifications with diet and exercise to achieve 5-10% weight loss 1, 3
• Adjunctive therapy: Metformin, particularly for those with insulin resistance or glucose intolerance 3

3. For Fertility Concerns

• First-line: Letrozole for ovulation induction 3
• Alternative options: Clomiphene citrate, gonadotropins, laparoscopic ovarian drilling 4

Monitoring and Follow-up

Women with PCOS should receive regular screening:

• Weight changes monitoring every 6-12 months
• Annual blood pressure checks
• Fasting lipid panel and glycemic control assessment
• Mental health screening for depression and anxiety
• Evaluation for sleep disorders 1, 3

Important Caveats

• Differential diagnosis: PCOS should be distinguished from isolated polycystic ovaries, which occur in 17-22% of women without hormonal abnormalities 1
• Phenotypic variation: Four recognized phenotypes exist with different long-term health implications 2
• Ethnic variations: East Asian women with PCOS have higher prevalence of metabolic syndrome despite lower BMI 1
• Terminology limitations: The name "PCOS" emphasizes ovarian aspects while underrepresenting the systemic metabolic nature of the disorder 5

PCOS requires lifelong management with regular monitoring for metabolic, cardiovascular, and psychological complications to improve quality of life and reduce morbidity and mortality.