What is the recommended evaluation and management for an adult woman presenting with new‑onset facial or truncal hirsutism?

Evaluation and Management of Female Hirsutism

Initial Clinical Assessment

For an adult woman presenting with new-onset facial or truncal hirsutism, begin by quantifying severity using the modified Ferriman-Gallwey (mFG) score and obtaining a morning total testosterone level; if mFG ≥8 or testosterone is elevated, proceed with full endocrine evaluation to exclude PCOS (70-80% of cases), androgen-secreting tumors, non-classical congenital adrenal hyperplasia, and Cushing's syndrome. 1

Key History Elements to Elicit

• Menstrual pattern: Cycles <23 days (polymenorrhea), >35 days (oligomenorrhea), or absent for >6 months (amenorrhea) suggest endocrine dysfunction 2
• Onset and progression: Rapid onset over weeks to months raises concern for androgen-secreting tumor 1
• Associated hyperandrogenic signs: Severe acne, androgenetic alopecia, clitoromegaly, truncal obesity (waist-hip ratio >0.9) 1, 2
• Metabolic indicators: Acanthosis nigricans (dark, velvety skin in neck/axillae) signals insulin resistance 1, 2
• Cushing features: Buffalo hump, moon facies, wide violaceous striae mandate endocrinology referral 2
• Medication history: Exogenous androgens, certain antiepileptics can cause hirsutism 1
• Family history: Strong genetic predisposition exists for PCOS and hair follicle androgen sensitivity 3

Physical Examination Priorities

• Pelvic examination: Assess for adnexal masses suggesting ovarian tumors 1
• Hirsutism quantification: Use mFG score; ≥8 is abnormal and warrants endocrine testing 4
• Signs of virilization: Clitoromegaly, deepening voice, increased muscle mass suggest severe hyperandrogenism 1

Laboratory Evaluation Algorithm

For Mild Hirsutism (mFG <8) Without Other Signs

• No routine endocrine testing required if isolated mild hirsutism without oligomenorrhea, infertility, clitoromegaly, or truncal obesity 1

For Moderate-to-Severe Hirsutism (mFG ≥8) or Any Red Flags

Initial panel:

• Morning total testosterone (preferably LC-MS/MS method for superior accuracy) 2
• Free testosterone or free androgen index (SHBG fluctuations affect interpretation) 2
• DHEA-S (normal effectively rules out adrenal causes including non-classical CAH and adrenal tumors) 2
• 17-hydroxyprogesterone (if clinical suspicion for non-classical CAH) 1
• TSH and prolactin (exclude hyperprolactinemia causing menstrual irregularity) 2
• LH and FSH (elevated testosterone with normal gonadotropins suggests PCOS) 2
• Fasting glucose/insulin and lipid panel (assess metabolic syndrome risk) 2

Critical thresholds:

• Total testosterone >200 ng/dL: Highly suggestive of androgen-secreting tumor; obtain imaging (pelvic ultrasound, adrenal CT/MRI) 1, 5
• Elevated 17-hydroxyprogesterone: Diagnostic for non-classical CAH 1

Imaging

• Pelvic ultrasound: Look for polycystic ovaries (>10 peripheral cysts 2-8 mm diameter with thickened stroma) in suspected PCOS 1

Treatment Algorithm

Step 1: First-Line Hormonal Therapy

Combined oral contraceptives (COCs) are first-line therapy for PCOS-related hirsutism, suppressing ovarian androgen production, increasing sex hormone-binding globulin, reducing 5-alpha-reductase activity, and blocking androgen receptors. 1

Pre-treatment screening:

• Absolute contraindications: Smoking ≥15 cigarettes/day at age ≥35, uncontrolled hypertension (≥160/100 mmHg), history of venous thromboembolism or ischemic heart disease, active liver disease, breast cancer, unexplained uterine bleeding 1
• Avoid androgenic progestins: Norethisterone derivatives and levonorgestrel worsen hirsutism 1
• Preferred formulations: Drospirenone-containing COCs offer additional anti-androgenic benefit 1

Expected timeline:

• Menstrual regularity: 1-3 cycles 1
• Hirsutism reduction: 6-12 months 1, 2

Step 2: Add Topical/Cosmetic Measures (Simultaneous with COCs)

• Topical eflornithine hydrochloride 13.9% cream: Inhibits hair growth, apply to facial areas 1, 3
• Hair removal techniques: Shaving, waxing, plucking, electrolysis, laser therapy 1

Step 3: Add Anti-Androgen if Inadequate Response at 6 Months

Spironolactone 50-100 mg daily (up to 200 mg studied safely) achieves clear skin or marked improvement in 66-85% of women 1

Mechanism:

• Competitively blocks androgen receptors 6
• Reduces testosterone synthesis 6
• May inhibit 5-alpha-reductase and increase SHBG 6

Safety considerations:

• Combination with drospirenone-containing COCs is safe without significant hyperkalemia risk in healthy young women 6
• Monitor potassium only in patients with compromised liver, adrenal, or renal function 6
• Contraception mandatory: Category C in pregnancy (risk of feminization of male fetus) 6

Alternative anti-androgens (if spironolactone contraindicated or ineffective):

• Finasteride 5 mg daily 1
• Flutamide (hepatotoxicity risk requires monitoring) 1
• Cyproterone acetate (not available in US) 1, 7

Step 4: Add Insulin-Sensitizing Agent for Metabolic Features

Metformin 500 mg 2-3 times daily for patients with obesity, acanthosis nigricans, or documented insulin resistance 1

Efficacy:

• 72% show significant improvement after 24 weeks 1
• Normalizes ovarian and adrenal androgen excess 1
• Best responders: menstrual-related flares or classic PCOS phenotype 1

Step 5: Weight Loss for Overweight/Obese Patients

5% weight reduction improves metabolic and reproductive abnormalities in obese women with PCOS-related hirsutism 1, 2

Special Populations and Referral Indications

Refer to Gynecology When:

• Infertility concerns: Clomiphene citrate preferred over COCs for ovulation induction 1
• Marked menstrual irregularities requiring reproductive management 1
• Desire for pregnancy: Adjust treatment plan accordingly 1

Refer to Endocrinology When:

• Cushing features: Buffalo hump, moon facies, violaceous striae 2
• Testosterone >200 ng/dL: Tumor workup required 1, 5
• Rapid virilization: Clitoromegaly, voice deepening, increased muscle mass 1
• Confirmed non-classical CAH: Requires glucocorticoid management 1

Monitoring and Long-Term Management

• Re-evaluate at 3-6 months: Assess clinical response (hirsutism, menstrual regularity, metabolic parameters) 1
• Screen for metabolic syndrome: PCOS increases long-term cardiovascular and diabetes risk 2
• Ensure endometrial surveillance: History of uterine polyp or chronic anovulation requires monitoring for unopposed estrogen exposure 1
• Counsel on fertility preservation: Some treatments affect reproductive potential 2

Common Pitfalls to Avoid

• Do not use topical antibiotics alone: Always combine with benzoyl peroxide to prevent resistance 1
• Do not delay tumor evaluation: Testosterone >200 ng/dL or rapid virilization requires urgent imaging 1, 5
• Do not prescribe spironolactone without contraception: Teratogenic risk mandates reliable birth control 6
• Do not expect rapid cosmetic improvement: Counsel patients that visible hirsutism reduction requires 6-12 months of hormonal therapy 1, 2