What is the initial workup for Polycystic Ovary Syndrome (PCOS)?

Initial Workup for Polycystic Ovary Syndrome (PCOS)

The initial workup for PCOS should include a thorough history focusing on menstrual irregularities and signs of androgen excess, physical examination for hyperandrogenism features, and laboratory tests including thyroid function, prolactin levels, testosterone levels, glucose tolerance testing, and lipid profile to rule out other disorders and assess metabolic complications. 1

History and Physical Examination Components

Key Historical Elements

• Onset and duration of signs of androgen excess
• Detailed menstrual history (irregularity, amenorrhea)
• Medication use, particularly exogenous androgens
• Lifestyle factors (diet, exercise, alcohol use, smoking)
• Family history of cardiovascular disease and diabetes 1

Physical Examination Focus

• Signs of hyperandrogenism:
  • Hirsutism (excessive body hair distribution)
  • Acne
  • Androgenic alopecia (balding)
  • Clitoromegaly
• Ovarian enlargement on pelvic examination
• Signs of insulin resistance:
  • Obesity (particularly central/abdominal)
  • Acanthosis nigricans (dark, velvety skin patches) 1

Laboratory Testing Algorithm

First-line Laboratory Tests

• Thyroid-stimulating hormone (TSH) to exclude thyroid dysfunction
• Prolactin level to rule out hyperprolactinemia
• Total testosterone or bioavailable/free testosterone levels to confirm hyperandrogenism
• Two-hour oral glucose tolerance test (75g glucose load) to screen for diabetes and glucose intolerance
• Fasting lipid profile (total cholesterol, LDL, HDL, triglycerides) 1

Additional Testing Based on Clinical Presentation

• If signs of Cushing's syndrome present (buffalo hump, moon facies, hypertension, abdominal striae, easy bruising):
  • Screen with appropriate tests for Cushing's syndrome
• If severe or rapid-onset virilization:
  • Consider testing for androgen-secreting tumors
• If suspected congenital adrenal hyperplasia:
  • 17-hydroxyprogesterone levels 1, 2

Diagnostic Approach

PCOS is a diagnosis of exclusion that requires ruling out other causes of androgen excess and ovulatory dysfunction, including:

• Cushing's syndrome
• Androgen-secreting tumors
• Exogenous androgen use
• Nonclassic congenital adrenal hyperplasia
• Acromegaly
• Primary hypothalamic amenorrhea
• Primary ovarian failure
• Thyroid disorders
• Hyperprolactinemia 1

Metabolic Assessment

All women with PCOS should undergo:

• Calculation of body mass index (BMI) and waist-hip ratio
• Screening for dyslipidemia with complete fasting lipid profile
• Screening for type 2 diabetes with fasting glucose and two-hour glucose tolerance test 1

Common Pitfalls and Caveats

• Delaying evaluation in adolescents is appropriate until two years post-menarche, as menstrual irregularity is common in early post-menarchal years 2
• Acanthosis nigricans may indicate associated insulinoma or malignancy (particularly adenocarcinoma of the stomach) and requires appropriate evaluation 1
• Not all women with PCOS are obese - up to 50% may have normal weight but still have metabolic abnormalities 3
• Marked virilization or rapid onset of symptoms requires immediate evaluation for potential androgen-secreting tumors 2
• PCOS has four recognized phenotypes with different long-term health implications, so clearly documenting the specific phenotype is important for proper management 4

The comprehensive initial workup is essential as PCOS is associated with significant long-term health risks including type 2 diabetes, metabolic syndrome, cardiovascular disease, and endometrial cancer, necessitating appropriate long-term follow-up and management 5.