Cervical carcinoma is usually treated by extensive total hysterectomy such as Okabayashi's procedure. However, since the introduction of the criteria for classification of stage Ia lesions in 1978 by the Registration Committee for Cervical Carcinoma of the Japan Association of Obstetrics and Gynecology, surgical procedures have been categorized in greater detail, and reduced operations have begun to be performed. Generally, simple hysterectomy is performed for stage 0 cervical carcinoma, and semi-extensive hysterectomy is indicated for stage Ia lesions. In this study, reduced operations were evaluated in 254 patients with stage 0 and 288 with stage Ia cervical carcinoma selected from 1,412 patients with cervical carcinoma treated at our department between 1976 and 1985. The time required for the operation was 90.8 +/- 34.8 min for simple, 126.7 +/- 36.5 min for semi-extensive, and 173.5 +/- 42.5 min for extensive hysterectomy. The volume of bleeding was 274.5 +/- 257.7 ml for simple, 545.4 +/- 758.2 ml for semi-extensive, and 805.7 +/- 441.6 ml for extensive hysterectomy. The frequency of blood transfusion increased with the increase in the extent of surgery, being 9.0, 22.9, and 61.8% for the respective operations. The incidence of postoperative complications (cystoplegia, renal disorders, fistula of the urinary tract, ileus and hepatitis) also increased to 12.4% for semi-extensive and 44.8% for extensive hysterectomy. Simple hysterectomy was sufficient for stage 0 lesions, and side effects associated with this operation were infrequent and mild. Curative conization was performed for 14 patients who expressed a desire to have babies, and no recurrence has been observed to date. Semi-extensive hysterectomy was performed in 77% of stage Ia patients, and extensive and simple operations were performed in 8.0% and 10.4%, respectively. Close histological evaluation and postoperative care were carried out, particularly for patients who underwent simple hysterectomy. All these patients are currently alive without signs of recurrence. Two patients received only curative conization due to their strong desire to have babies and are currently being followed up. Both of these patients showed small degrees of interstitial invasion of less than 2mm.