What causes hair loss in women? Warning signs of thinning hair that should Not be ignored.

A woman experiences severe hair loss when washing her hair. After washing, when she combs her hair, clumps of hair falls out in the bathroom.

Hair Loss in Women

Overview Hair loss in women is common and can be distressing. It ranges from increased shedding to visible thinning and patchy baldness. Causes are often multifactorial, involving genetics, hormones, medical conditions, nutritional deficiencies, medications, stress and haircare practices. Accurate assessment and early intervention improve outcomes.

Common patterns and types

• Female pattern hair loss (FPHL): Gradual thinning over the crown and centre parting with preservation of the frontal hairline in early stages. Often hereditary and related to hormonal sensitivity.

• Telogen effluvium: Diffuse increased shedding following a triggering event (illness, surgery, severe stress, childbirth, rapid weight loss, certain medications). Usually reversible within months when the trigger resolves.

• Alopecia areata: Autoimmune, patchy hair loss that can appear suddenly; may progress to complete scalp hair loss (alopecia totalis) or whole-body hair loss (alopecia universalis).

• Traction alopecia: Localised hair loss caused by chronic tension from tight hairstyles, extensions or certain hair tools.

• Cicatricial (scarring) alopecia: Group of conditions where inflammation destroys hair follicles, replaced by scar tissue; hair loss is permanent once scarring has occurred.

• Combination causes: Many women have more than one contributing factor.

Causes and contributing factors

• Genetic predisposition (androgen-sensitive follicles).

• Hormonal changes: pregnancy, childbirth, menopause, polycystic ovary syndrome (PCOS), thyroid disease.

• Medical conditions: autoimmune disease, iron-deficiency anaemia, chronic illness.

• Nutritional deficiencies: iron, vitamin D, protein, zinc, biotin (where deficiency is proven).

• Medications: anticoagulants, retinoids, some antidepressants, chemotherapy.

• Physical or emotional stressors.

• Haircare and styling practices: chemical treatments, heat, tight hairstyles.

• Age: hair density and growth rate typically decline with age.

Symptoms to watch for

• Increased hair shedding (large amounts on pillow, shower, brush).

• Noticeably wider part or overall thinning.

• Small round patches of hair loss.

• Itchy, painful or scarred scalp.

• Sudden or rapid hair loss — seek prompt assessment.

What causes hair loss in women?

Hair loss in women can result from many different causes. Understanding the underlying reason is important for effective treatment. Common causes include:

• Androgenetic alopecia (female pattern hair loss)

  • The most common cause; characterised by diffuse thinning over the crown and widening of the central parting.

  • Driven by genetic susceptibility and sensitivity of hair follicles to androgens (male hormones), often progressing gradually.

• Telogen effluvium

  • Temporary, diffuse shedding when many hairs prematurely enter the resting (telogen) phase.

  • Triggered by physical or emotional stress, illness, surgery, rapid weight loss, childbirth, fever, major life events or abrupt stopping of hormonal contraception or certain medications.

  • Typically begins 2–3 months after the trigger and may last several months.

• Alopecia areata

  • An autoimmune condition causing patchy, well-defined hair loss; can affect the scalp and body.

  • May progress to total scalp loss (alopecia totalis) or whole-body loss (alopecia universalis) in some cases.

  • Often unpredictable; associated with other autoimmune conditions in some patients.

• Traction alopecia

  • Hair loss caused by repeated mechanical tension on hair follicles from tight hairstyles (tight ponytails, braids, extensions) or certain headgear.

  • Early stages are reversible if tension is stopped; prolonged traction can cause permanent scarring and follicle loss.

• Cicatricial (scarring) alopecia

  • A group of conditions where inflammation destroys hair follicles and replaces them with scar tissue, causing permanent loss.

  • Causes include lichen planopilaris, frontal fibrosing alopecia, discoid lupus erythematosus and infections.

• Hormonal imbalances

  • Thyroid disease (hypothyroidism or hyperthyroidism) can cause diffuse hair thinning.

  • Polycystic ovary syndrome (PCOS) may cause androgen-related thinning.

  • Menopause and changes in oestrogen levels can lead to hair thinning.

• Nutritional deficiencies

  • Low iron (iron-deficiency anaemia), vitamin D deficiency, low protein intake and deficiencies of zinc, biotin or other micronutrients can contribute to hair shedding and poor hair growth.

• Medications and medical treatments

  • Chemotherapy commonly causes profound hair loss.

  • Other drugs (anticoagulants, retinoids, some antidepressants, blood pressure medications, and hormonal therapies) can cause hair thinning or telogen effluvium.

• Chronic illness and systemic diseases

  • Major chronic conditions (autoimmune diseases, chronic infections, severe metabolic disease) can cause hair loss.

  • Skin conditions affecting the scalp (seborrhoeic dermatitis, psoriasis, fungal infections) can contribute to shedding or damage.

• Ageing and genetics

  • Hair density and growth rate decline with age; genetic factors influence hair thickness and longevity.

• Environmental and cosmetic factors

  • Excessive heat styling, chemical treatments (perms, bleaching), harsh brushing and overuse of styling products can weaken hair and cause breakage that may appear as thinning.

Female Pattern Hair Loss

Overview Female Pattern Hair Loss (FPHL), also known as female androgenetic alopecia, is the common form of progressive hair thinning in women. It typically presents as diffuse thinning over the crown and widening of the central parting, while the frontal hairline is often preserved. Onset can occur after puberty but is most common from the 30s onwards, with prevalence increasing with age.

Causes and risk factors

• Genetics: A family history of hair loss increases risk. Multiple genes contribute to susceptibility.

• Hormonal influences: Androgens may play a role, though women with FPHL often have normal circulating androgen levels. Local scalp sensitivity to androgens and changes across life stages (puberty, pregnancy, perimenopause, menopause) can affect hair growth.

• Age: Age-related changes in hair cycling and follicle miniaturisation are significant.

• Medical conditions and medications: Thyroid disease, iron deficiency, chronic illness, polycystic ovary syndrome (PCOS) and certain drugs can exacerbate thinning.

• Lifestyle and health factors: Significant physiological stress, poor nutrition, rapid weight loss, and chronic inflammatory scalp conditions may contribute.

When to see a Hair specialist:

• Rapid or extensive hair loss.

• Patchy or localized hair loss.

• Scalp symptoms such as soreness, scaling or scarring.

• Suspected underlying medical condition.

• If over-the-counter measures have failed after several months.