Female pattern hair loss (Female pattern hair loss (FPHL))

Female pattern hair loss (FPHL) is androgenetic alopecia presenting in women. The biology is the same DHT-androgen receptor mechanism as male AGA but expressed in a different distribution: diffuse thinning across the central scalp with the frontal hairline preserved.

The visual classification scales are the Ludwig scale (I to III) and the Sinclair scale (1 to 5). The “Christmas tree” pattern, where the widening part is broader at the front and narrower at the back, is characteristic.

Workup typically includes androgen panel (testosterone, DHEAS, prolactin), iron studies (ferritin), thyroid (TSH), and consideration of PCOS in younger women with associated features (acne, hirsutism, irregular periods).

Treatment differs from male AGA. Topical 5% minoxidil is first-line. Spironolactone and low-dose oral minoxidil are common second-line additions. Oral finasteride is used off-label in postmenopausal women; it is not recommended in women of reproductive age because of risk of feminisation of a male foetus.