A randomized trial comparing two methods of cold knife conization with laser conization. In a randomized study, 62 women were submitted to cold knife conization with application of Sturmdorf sutures, 60 to cold knife conization without sutures, and 61 to laser conization. Early hemorrhage occurred in 1.6, 13.3, and 6.6% of women, respectively (P less than .05), and late hemorrhage in 15.3, 3.6, and 11.7%, respectively. Considering early and late hemorrhage together, there was no significant difference among the three treatment groups. Dysmenorrhea tended to be more common after application of Sturmdorf sutures, as it was reported by 27.8, 13.2, and 14.3% of patients, respectively, but the difference was not statistically significant. Dysmenorrhea occurred in 13% of the cases with a cone height of 20 mm or less and in 26% of the cases with a cone height greater than 20 mm (P less than .05). Endocervical cells were present significantly more often after sampling with a cytobrush than with a cotton swab (P less than .0001), whereas the method of conization had no influence. In smears obtained with a cytobrush, endocervical cells were present in 88.0, 84.9, and 82.5% of the cases; in smears obtained with a cotton swab, endocervical cells were present in 46.6, 57.7, and 54.5%, respectively. We conclude that cold knife conization without Sturmdorf sutures is about equal to laser conization in overall complications, but the laser is preferable for outpatient treatment because of a lower frequency of early hemorrhage. Sturmdorf sutures should be avoided. Smears at follow-up should be taken with a cytobrush and a wooden spatula. 