1. Genetic (Hereditary) Hair Loss

Condition: Female pattern hair loss (androgenetic alopecia)
Description: Gradual thinning on the crown and top of the scalp.
Cause: Inherited sensitivity of hair follicles to androgens (male hormones).
Timing: Often starts after menopause, but can occur earlier.

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2. Hormonal Changes

Causes include:

• Pregnancy, childbirth, or menopause

• Starting or stopping birth control pills

• Thyroid disorders (hypothyroidism or hyperthyroidism)
  Mechanism: Hormonal fluctuations can disrupt the normal hair growth cycle, leading to shedding or thinning.

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3. Medical Conditions

Common causes:

• Polycystic ovary syndrome (PCOS), which elevates androgen levels

• Autoimmune diseases such as alopecia areata, where the immune system attacks hair follicles

• Scalp infections, such as fungal infections (ringworm)

• Chronic illnesses or high fevers

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4. Nutritional Deficiencies

Hair requires adequate nutrients for growth. Deficiencies may include:

• Iron (especially in menstruating women)

• Zinc

• Vitamin D

• Protein

• B vitamins (especially biotin and B12)
  Crash diets or eating disorders can also trigger telogen effluvium (temporary hair shedding).

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5. Stress and Psychological Factors

Condition: Telogen effluvium
Cause: Major physical or emotional stress (such as surgery, trauma, illness, or grief).
Effect: More hairs enter the shedding phase, typically 2–3 months after the triggering event.

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6. Hair Care and Styling Habits

• Traction alopecia: From tight hairstyles (braids, ponytails, extensions)

• Chemical damage: From frequent coloring, straightening, or perming

• Heat damage: From overuse of straighteners or blow dryers

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7. Medications and Treatments

Certain drugs can cause hair loss as a side effect, including:

• Chemotherapy or radiation therapy

• Antidepressants

• Blood thinners

• Beta-blockers

• Retinoids

• Birth control pills (on starting or stopping)

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8. Aging

As women age, hair naturally becomes finer and growth slows due to reduced follicle activity and hormonal changes.