The Ludwig scale classifies female pattern androgenetic alopecia on a three-stage system, from I to III.
| Stage | Description |
|---|---|
| Stage I | Mild thinning at the crown; the hairline is generally preserved |
| Stage II | The center part visibly widens and scalp becomes visible |
| Stage III | Widespread, pronounced hair loss at the crown |
Unlike male pattern loss, the hairline in women is typically preserved, and loss develops in a more diffuse pattern. This distinction is critical when assessing candidacy for transplantation (see DPA vs. DUPA).
Clinical note: The Ludwig scale alone doesn't determine candidacy for transplant — donor area density and whether thinning is localized or scalp-wide must also be assessed.