Female Androgenetic Alopecia

Introduction

Female androgenetic alopecia (FAGA), also known as female pattern hair loss, is the most common cause of hair loss in women. It is a chronic, progressive condition characterised by a gradual reduction in hair density, particularly in the central scalp. While the exact prevalence is unclear, it increases with age and can have a significant psychological impact on affected individuals. Unlike male pattern baldness, FAGA rarely leads to complete baldness.

Aetiology and Risk Factors

The aetiology of female androgenetic alopecia involves a combination of genetic, hormonal, and environmental factors:

• Genetic Predisposition: A family history of androgenetic alopecia in either the maternal or paternal lineage increases the risk.
• Hormonal Influence: Androgens (male hormones) are believed to play a role in FAGA, although their exact contribution is less clear than in male pattern baldness. Women with conditions that increase androgen levels, such as polycystic ovary syndrome (PCOS), are at higher risk.
• Age: The incidence of FAGA increases with age, particularly after menopause, when hormonal changes may exacerbate hair thinning.
• Other Factors: Stress, poor diet, and certain medical conditions (e.g., iron deficiency, thyroid disorders) may contribute to or exacerbate hair loss.

Clinical Presentation

Female androgenetic alopecia typically presents with the following features:

• Gradual Thinning: Hair thinning occurs gradually, primarily affecting the central part of the scalp. The hairline usually remains intact, unlike in male pattern baldness.
• Widening Part: One of the earliest signs is a widening of the central parting of the hair, often noticeable when styling the hair.
• Diffuse Hair Loss: While the central scalp is most affected, some women experience diffuse thinning across the entire scalp.
• Miniaturisation: Affected hair follicles produce thinner, shorter, and less pigmented hairs, known as vellus hairs, which contribute to the appearance of thinning.
• Ludwig Classification: FAGA is often classified using the Ludwig scale, which ranges from Type I (mild thinning) to Type III (severe thinning with a visible scalp).

Diagnosis

The diagnosis of female androgenetic alopecia is primarily clinical, based on the characteristic pattern of hair loss and patient history:

• History: Take a detailed history, including the onset and progression of hair loss, family history of androgenetic alopecia, menstrual history, and any associated symptoms (e.g., hirsutism, acne).
• Physical Examination: Examine the scalp for the pattern of hair loss, hair miniaturisation, and any signs of scalp inflammation or scarring that might suggest an alternative diagnosis.
• Dermatoscopy: Dermatoscopy can help visualise miniaturised hairs, a key feature of androgenetic alopecia, and differentiate it from other causes of hair loss.
• Blood Tests: Blood tests may be performed to rule out other causes of hair loss, such as thyroid function tests, serum ferritin (for iron deficiency), and androgen levels, particularly in the presence of other signs of hyperandrogenism.
• Biopsy: A scalp biopsy is rarely required but may be performed in cases where the diagnosis is uncertain or where other conditions (e.g., chronic telogen effluvium or scarring alopecia) are suspected.

Management and Treatment

The management of female androgenetic alopecia involves both medical and cosmetic approaches, aiming to slow hair loss, promote hair regrowth, and improve the patient’s quality of life:

1. Topical Treatments

• Minoxidil: Minoxidil 2% or 5% solution or foam is the first-line treatment for FAGA. It is applied once or twice daily to the affected areas of the scalp. Minoxidil works by prolonging the anagen (growth) phase of the hair cycle and increasing blood flow to the hair follicles. It may take 3-6 months to see noticeable results, and continuous use is required to maintain hair growth.
• Side Effects: Potential side effects of minoxidil include scalp irritation, unwanted facial hair growth, and initial shedding, which typically resolves after the first few months of treatment.

2. Oral Treatments

• Spironolactone: An oral anti-androgen medication that can be used in women with signs of hyperandrogenism (e.g., hirsutism, acne) or those who do not respond to topical minoxidil. Spironolactone blocks androgen receptors and reduces androgen production. It is usually started at a low dose and gradually increased.
• Finasteride: Oral finasteride, a 5-alpha reductase inhibitor, is more commonly used in male androgenetic alopecia but may be considered off-label in postmenopausal women with FAGA under specialist supervision. It is not typically used in premenopausal women due to the risk of teratogenicity.
• Side Effects: Potential side effects of spironolactone include menstrual irregularities, breast tenderness, and dizziness. Finasteride may cause sexual dysfunction and should be used with caution.

3. Cosmetic Treatments

• Camouflage Products: Hair fibres, powders, and sprays can be used to conceal thinning areas and improve the appearance of hair density.
• Wigs and Hairpieces: Wigs, hairpieces, or extensions can be a practical option for women with significant hair loss.
• Platelet-Rich Plasma (PRP) Therapy: PRP involves injecting the patient’s own platelet-rich plasma into the scalp to stimulate hair growth. While evidence is still emerging, it may offer benefits for some patients.

4. Lifestyle and Supportive Care

• Diet and Nutrition: Ensure adequate intake of essential nutrients for hair health, such as iron, vitamin D, and biotin. A balanced diet can support overall hair health.
• Stress Management: Stress can exacerbate hair loss, so stress management techniques such as mindfulness, relaxation exercises, and counselling may be beneficial.
• Regular Follow-Up: Regular follow-up with a healthcare provider is important to monitor progress, manage side effects, and adjust treatment as necessary.

When to Refer

Referral to a dermatologist or specialist may be necessary in the following situations:

• Severe or Refractory Cases: If FAGA does not respond to standard treatments or if the condition is severe, referral to a dermatologist is advised.
• Diagnostic Uncertainty: If the diagnosis is unclear or if other conditions are suspected (e.g., scarring alopecia), a dermatologist’s input may be necessary.
• Consideration for Hair Transplantation: Some women with stable FAGA may be candidates for hair transplantation, a surgical option that involves moving hair follicles from one part of the scalp to another.

References

1. British Association of Dermatologists (2024) Guidelines for the Management of Female Androgenetic Alopecia. Available at: https://www.bad.org.uk (Accessed: 26 August 2024).
2. National Institute for Health and Care Excellence (2024) Female Pattern Hair Loss: Diagnosis and Management. Available at: https://www.nice.org.uk/guidance/ng104 (Accessed: 26 August 2024).
3. British National Formulary (2024) Topical and Oral Treatments for Dermatological Conditions. Available at: https://bnf.nice.org.uk/ (Accessed: 26 August 2024).