Study objectives: To evaluate the safety and efficacy of thermal balloon endometrial ablation in women with menorrhagia, and to identify factors influencing outcome.
Design: Prospective, observational study (Canadian Task Force classification II-2).
Setting: Three Canadian university-affiliated teaching hospitals.
Patients: One hundred twenty-one women suffering from menorrhagia serious enough to make them candidates for endometrial ablation or hysterectomy. Patients without obvious structural or (pre)malignant abnormalities were included if their uterine cavities sounded to less than 12 cm, they were in good health, and had undergone hysteroscopy or pelvic ultrasound and endometrial biopsy within 6 months and had a normal Papanicolaou smear within 1 year.
Interventions: A balloon catheter was placed through the cervix and after inflation in the endometrial cavity with 5% dextrose in water, was heated to 87 +/- 5 degrees C. Two-thirds of patients avoided general anesthesia and very few required cervical dilatation to admit the 4.5-mm diameter catheter. Balloon pressures were 90 to 140 mm Hg in 13 patients; pressures between 140 and 190 mm Hg were well tolerated by the rest. Nineteen women underwent 12 minutes of therapy, and the rest had 8-minute sessions.
Measurements and main results: No intraoperative complications occurred, and minor postoperative morbidity occurred in 4% of patients. Preoperative and postoperative bleeding was assessed by pad counts and patient self-reports. The degree of dysmenorrhea was recorded similarly. A paired t test was used to compare pretreatment with posttreatment pad counts. A Wilcoxon signed rank test was employed to evaluate the effect of treatment on dysmenorrhea. The effects on outcome of several independent variables were analyzed by multiple and logistic regression. Success of the procedure was constant over the year (range 86-90%). Treatment led to significant decreases in menstrual flow, duration, and pain (p <0.0001). No significant effects of parity, uterine position or cavity depth, timing, or various endometrial-thinning regimens were found. Increasing age was significantly associated with increased odds of success (p < 0.05). Excluding the 19 women who underwent 12 minutes of therapy did not change statistical results, whereas excluding the 13 treated with balloon pressures less than 140 mm Hg improved the results. Conclusion. The facts that bleeding and dysmenorrhea were significantly reduced by thermal balloon endometrial ablation, that no intraoperative complication occurred, and that postoperative morbidity was minimal, lead us to conclude that this is potentially a safe and effective technique. Larger studies and longer follow-up are required to substantiate this impression.