OBJECTIVE Our goal was to evaluate short-term (3 months) and long-term (1 year) treatment of vulvar lichen sclerosus, by comparing topical application of testosterone propionate 2% in petrolatum with the corticosteroid clobetasol dipropionate 0.05%. METHODS There were 20 women in each treatment group. The patients' symptoms and the gynecologist's examination findings were recorded before treatment, at 3 months, and at 1 year after initiation of therapy. RESULTS The symptomatic (subjective) effect of clobetasol treatment was similar to that of testosterone at the 3-month follow-up (p < or = 0.34), although objectively the signs of lichen sclerosus had improved more in the clobetasol group (p < or = 0.033). Both symptoms and signs were significantly more improved in the clobetasol-treated group at the 1-year follow-up examination (p < or = 0.02). Seventy percent of women treated by testosterone discontinued treatment because of a lack of response, whereas only 10% of the women treated with clobetasol stopped the treatment for that reason (p < or = 0.00042). CONCLUSIONS Clobetasol is more effective than testosterone in the treatment of women with lichen sclerosus, especially in the long term.