Objective: To describe registry methods and baseline patient demographics from a national sample of women undergoing uterine artery embolization for uterine leiomyomata. Methods: Interventional radiology practices were recruited to submit data by a secure Web site on women undergoing uterine artery embolization for symptomatic leiomyomata. Baseline data included patient demographics, prior medical, surgical, and obstetrical history, uterine anatomy, and quality- of- life measures. Subsequent data collected included details of the uterine artery embolization procedure and hospital stay and outcomes at 30 days; patients were also offered the opportunity to participate in longer- term follow- up. Characteristics of white and African- American women were compared using t tests, χ 2, or Wilcoxon rank- sum tests as appropriate. Results: As of December 31, 2002, 3,319 uterine artery embolization cases had been entered into the registry by 72 sites; number of patients entered by individual sites ranged from 1 to 514. Of these patients, 95.4% consented to participation in the short- term outcomes registry. Forty- eight percent of patients were African American, and 44.4% were white and non- Hispanic. Heavy menstrual bleeding was the single most bothersome symptom in 64.3% of patients. Compared with white non- Hispanic women, African- American women were significantly younger, more likely to be obese, had larger uteri and more numerous leiomyomata, more severe symptoms, and poorer quality- of- life scores before treatment. Conclusion: It is feasible to collect prospective data on new techn ologies. The FIBROID Registry prospec- tively collected data on more than 3,000 women undergoing uterine artery embolization for symptomatic leiomyomata. Baseline patient characteristics of this patient population seem to be similar to those of women undergoing other procedures for leiomyomata. Objective: To describe registry methods and baseline patient demographics from a national sample of women undergoing uterine artery embolization for uterine leiomyomata. Methods: Interventional radiology practices were recruited to submit data by a secure Web site on women undergoing uterine artery embolization for symptomatic leiomyomata. Baseline data included patient demographics, prior medical, surgical, and obstetrical history, uterine anatomy, and quality- of- life measures. Subsequent data collected including details of the uterine artery embolization procedure and hospital stay and outcomes at 30 days; patients were also offered the opportunity to participate in longer- term follow-up. Characteristics of white and African- American women were compared using t tests, χ 2, or Wilcoxon rank-sum tests as appropriate. Results: As of December 31, 2002, 3,319 uterine artery embolization cases had been entered into the registry by 72 sites; number of patients entered by individual si tes ranged from 1 to 514. Of these patients, 95.4% consented to participation in the short-term outcomes registry. Forty- eight percent of patients were African American, and 44.4% were white and non-Hispanic. Heavy menstrual bleeding was the single Compared with white non- Hispanic women, African- American women were significantly younger, more likely to be obese, had larger uteri and more numerous leiomyomata, more severe symptoms, and poorer quality- of- life scores before treatment. Conclusion: It is feasible to collect prospective data on new technologies. The FIBROID Registry prospec- tively collected data on more than 3,000 women undergoing uterine artery embolization for symptomatic leiomyomata. Baseline patient characteristics of this patient population seem to be similar to those of women undergoing other procedures for leiomyomata.