Recent publications have suggested that use of the Pipelle endometrial suction curette is a safe and effective method by which to obtain samples of endometrial tissue. To address this issue, we performed a randomized clinical trial comparing the Pipelle to the Tis-u-trap in 156 patients. The Pipelle was as effective as the Tis-u-trap in obtaining endometrial samples in both the adequacy of the specimen (Pipelle 88%, Tis-u-trap 84%) and the quality of the specimen (P = .26). This trial confirms the favorable observational reports on the use of the Pipelle for endometrial biopsy.