During 1990, we performed hysteroscopic incision of uterine septum in 23 women with repeated abortion. The patients were allocated randomly to metroplasty with resectoscope (12 patients in group 1) or microscissors (11 patients in group 2) to compare surgical feasibility and anatomic results with these instruments. The uterine cavity was distended by instillation of sorbitol and mannitol solution under manometric control. Two patients in group 1 and three in group 2 had a complete septum. In group 1, the mean operating time, plus or minus standard deviation (S.D.), was 22 +/- 6 minutes compared with 17 +/- 5 minutes in group 2 (p = 0.06). The mean amount of distension medium used, plus or minus S.D., was 890 +/- 153 milliliters in group 1 versus 671 +/- 170 milliliters in group 2 (p = 0.003). One woman in group 1 with complete uterine septum had a uterine perforation that was managed conservatively. Postoperative morbidity for the entire series was negligible. At follow-up ultrasonography and hysteroscopy performed two months postoperatively, a residual fundal notch > or = 1 centimeter deep was detected and corrected in four patients in group 1 and two in group 2. Our findings indicate that, in terms of operating time and efficacy, the resectoscope and microscissors are equally valid instruments to correct a septate uterus, with a feasibility rate of 100 percent.