Objective: Our purpose was to demonstrate that intrauterine adhesions and hematometra do not occur after a partial rollerball endometrial ablation and that menorrhagia can be successfully treated by this procedure for patients without deep adenomyosis. Study Design: Fifty patients with hysteroscopically normal-appearing cavities (without gross polyps or submucous fibroid tumors) had a partial endometrial ablation for menorrhagia and were followed up for >3 years. A partial ablation is defined as ablation of only the anterior or posterior endometrial wall and avoidance of the cornual areas. A posterior myometrial biopsy to determine the depth of adenomyosis was performed and correlated with outcome. The intrauterine cavity was evaluated postoperatively for adhesions. Results: Patients without deep adenomyosis had good outcome after partial ablation. No postoperative intrauterine adhesions were found. Conclusion: Partial endometrial ablation can successfully treat menorrhagia in patients without deep adenomyosis. It does not cause intrauterine adhesions, which may lead to hematometra and potentially delay the diagnosis of endometrial cancer. (Am J Obstet Gynecol 1999;180:1512-21.)