To record the clinical features, symptomatic response to topical steroids, and resolution of clinical signs in a large cohort of female patients with vulvar lichen sclerosus.Design: Descriptive cohort study with a mean follow-up of 66 months. Setting:The vulvar clinics of a teaching hospital and of a district general hospital in Oxfordshire, England.Patients: Three hundred twenty-seven patients (74 girls and 253 women) with a definite clinical diagnosis of vulvar lichen sclerosus. Interventions:The patients received topical steroids as part of their normal care.Main Outcome Measures: Symptomatic response to treatment (good, partial, or poor); response of the vulvar signs (total, partial, minor, or poor); and the presence or absence of moderate or severe scarring. Results:The mean age at onset was 5.4 years in girls and 55.1 years in women and first-choice therapy was an ultrapotent topical steroid for 50% of the girls and 89% of the women. Response to treatment was recorded in 255 patients. In 244 patients (96%) symptoms improved with treatment, as 168 (66%) became symptom free and 76 (30%) showed partial response; 11 (4%) had poor response. Among the 253 patients in whom a response of the vulvar signs to topical steroid was recorded, 58 (23%) showed total response, with return to normal skin texture and color; and 173 (68%) showed partial, 18 (7%) showed minor, and 4 (2%) showed poor response. Moderate or severe scarring occurred less often in girls (PϽ.001). Squamous cell carcinoma developed in 6 women (2.4%). Conclusion:Topical ultrapotent steroid is an effective treatment for vulvar lichen sclerosus, giving relief of symptoms in most and completely reversing the skin changes in approximately one fifth of patients.