Risk Factors for Uterine Fibroids: A Case Control Study

Uterine leiomyomas are the leading cause of hysterectomy in the United States, accounting for over 200,000 procedures each year. Leiomyoma is a common condition with many tumors being asymptomatic. It is not known which women who have fibroids will develop clinical symptoms. In 1996-1999 the NIEHS Uterine Fibroid Study enrolled 1245 randomly selected premenopausal women, aged 35 to 49, who had been randomly selected from the membership roles of George Washington University Health Plan, a large prepaid health plan in Washington, D.C. Slightly over half of the participants were African American. Participants were asked about prior diagnoses of uterine leiomyomas, and 87% were examined by abdominal/transvaginal ultrasound to screen for uterine leiomyoma. Sixty-two percent of the 1245 had either had a prior diagnosis of leiomyoma or had sonogram evidence of the condition. Study Objectives: 1. Monitor fibroid-related symptoms over time (Two follow-ups over a five-year period). 2. Measure the proportion of women who undergo major medical intervention (hysteroscopic resection, uterine artery embolization, laser coagulation, myomectomy, or hysterectomy). 3. Identify risk factors for increased symptom severity. 4. Identify risk factors for treatment intervention. Methods: Premenopausal participants in the Uterine Fibroid Study (1996-1999) will be recontacted twice during the years 2001 - 2005 to obtain information about leiomyoma-related symptoms and medical or surgical treatments. Data will be collected with a computer-assisted telephone interview. Medical records of ultrasound or MRI examinations and major medical or surgical interventions will be abstracted to verify medical follow-up and treatment. Significance: The presence of leiomyomas can be identified with ultrasound screening when the condition is asymptomatic. However, no data are available that allow clinicians to predict which women will experience morbidity. This longitudinal study will trace disease progression, and identify factors related to increased symptom severity and medical/surgical treatment. The findings could then be used to develop a systematic scoring system that can be used to identify women at high risk.