BACKGROUND Long-term follow-up 11 years after endometrial ablation. METHODS A questionnaire on menstruation, hormone treatment, and surgery was conducted among women who had 420 endometrial ablations during the 1990-96 period; the results were analysed in conjunction with register data on cancer, surgery and obstetric history. RESULTS A total of 82% of the questionnaires were answered. In all, 26% of the women who received hormone treatment after ablation subsequently had a hysterectomy compared with 34% of the women who received no hormone treatment after ablation (p = 0,28; chi(2)-test). Hysterectomy was associated with occurrence of meno-/metrorrhagia. However, the number of women who were hysterectomised was distributed evenly throughout the duration of hormone treatment. The time of hormone treatment according to the ablation was not associated with the distribution of meno/metrorrhagia or whether the women subsequently had a hysterectomy. We observed three women with incidental endometrial cancer at follow-up, here of one in a polyp, and the expected number was 6,8 cases. CONCLUSIONS Endometrial ablation is a good treatment for menorrhagia, but in 40% of cases it is followed by further gynaecological surgery. Hormone treatment was not found to have any effect on the course of events. No additional cases of incidental cancer were noted at follow-up.