Polycystic Ovary Syndrome (PCOS)

Summary

Polycystic Ovary Syndrome (PCOS) is a common endocrine disorder affecting 6–20% of reproductive-age women. It involves ovulatory dysfunction, hyperandrogenism, and/or polycystic ovarian morphology (Rotterdam criteria, 2003). PCOS presents with menstrual irregularity, hirsutism, acne, infertility, and obesity, and is linked to insulin resistance, metabolic syndrome, and cardiovascular risk. Diagnosis is clinical, supported by labs and ultrasound. Management is individualized, focusing on lifestyle changes, hormonal therapy, metabolic control, and fertility treatment when needed.

Definition

PCOS is a chronic endocrine disorder characterized by ovarian dysfunction and androgen excess.
According to the Rotterdam criteria (2003)—endorsed by the ESHRE/ASRM consensus—a diagnosis of PCOS requires ≥2 of the following 3 features, with exclusion of other causes such as Cushing’s syndrome, thyroid disease, or hyperprolactinemia:

1. Oligo- or anovulation (irregular or absent menstrual cycles)

2. Clinical and/or biochemical hyperandrogenism (e.g., hirsutism, acne, elevated serum androgens)

3. Polycystic ovarian morphology (PCOM) on ultrasound
   → ≥20 follicles (2–9 mm) and/or ovarian volume >10 mL in either ovary (using transducers ≥8 MHz)
   

Epidemiology and Risk Factors

• Prevalence: 6–20% of reproductive-aged women (varies by criteria used)

• Familial tendency is associated with genetic susceptibility and insulin resistance

• Risk increases with obesity, type 2 diabetes, and a family history of PCOS

Pathophysiology

PCOS arises from interrelated neuroendocrine, metabolic, and ovarian dysfunction:

• ↑ GnRH pulse frequency → ↑ LH secretion → theca cell androgen production

• Insulin resistance and hyperinsulinemia enhance ovarian androgen synthesis and suppress hepatic SHBG → ↑ free testosterone

• Anovulation results from impaired follicular maturation → multiple immature follicles

• Low-grade inflammation contributes to metabolic and vascular complications

Clinical Presentation

• Reproductive and Menstrual Features:

• Oligomenorrhea or amenorrhea (cycles >35 days apart or <8 per year)

• Anovulatory infertility due to failed follicular rupture

• Polycystic ovaries on imaging (string-of-pearls pattern)

• Hyperandrogenic Features:

• Hirsutism (face, chest, abdomen, back)

• Acne, seborrhea, androgenic alopecia

• Metabolic and Other Manifestations:

• Central obesity and insulin resistance

• Dyslipidemia, glucose intolerance, type 2 diabetes

• Acanthosis nigricans (marker of hyperinsulinemia)

• Mood disorders (anxiety, depression) and sleep apnea

Diagnostic Evaluation

1. Clinical Assessment

• History of menstrual irregularity, infertility, and signs of androgen excess

• BMI, waist circumference, hirsutism scoring (Ferriman–Gallwey scale)

2. Laboratory Tests

3. Imaging

• Transvaginal ultrasound: ≥20 follicles (2–9 mm) or ovarian volume >10 mL
  “String of pearls” appearance is characteristic but not diagnostic in isolation.

Diagnostic Criteria (Rotterdam 2003)

Diagnosis requires ≥2 of the following 3 findings:

Management

Management is individualized and depends on symptom profile and reproductive goals.

Complications

• Infertility from chronic anovulation

• Endometrial hyperplasia/carcinoma (unopposed estrogen)

• Metabolic syndrome & type 2 diabetes

• Cardiovascular disease (hypertension, atherosclerosis)

• Obstructive sleep apnea

• Depression and anxiety