The aim of this prospective study was to investigate factors predicting choice of treatment for excessive menstrual bleeding, with special emphasis on women's pre-treatment preference. A cohort of women with heavy menstruation and their treatment process in gynaecology outpatient clinics were followed-up for 1yr. A total of 383 35-54-yr-old women attending 14 Finnish hospitals participated. They completed a questionnaire before their first outpatient clinic visit, and postal follow-ups were conducted 3 and 12 months later. Information on treatment(s) during the follow-up was taken from medical records and questionnaires. The choice between hysterectomy and conservative treatments, and fulfillment of pre-treatment preference were the main outcome measures. During the 1-yr follow-up, 51% (n=196) of the women underwent hysterectomy and nine were still awaiting it, 12% (n=44) had a minor surgical procedure, 11% (n=41) had oral medication, 9% (n=33) used a hormonal intrauterine system, and nine women changed preventive method. Forty-two women (11%) reported having had no treatment. Data on previous treatments suggested that conservative treatment modalities were under-used. Most of the treatment decisions were made within the first 3-month period. Women's pre-treatment preference was the strongest predictor of chosen treatment. Unemployment, irregular periods and anxiety decreased the probability of a decision for hysterectomy, while pelvic pain and inconvenience due to bleeding increased it. The treatment plan accorded with pre-treatment preference in 72% of the women preferring hysterectomy and in 74% of those preferring a conservative option.