OBJECTIVE To compare two endometrial sampling devices, pipelle and vacurette, performed during hysteroscopy, based on the quality of material obtained and pain during the sampling. METHODS During the period from 01.03.96 to 01.12.97, 200 patients were consecutively randomized in a single blind prospective study. Efficacity was evaluated on the quality of material obtained and pain was graded on a scale of 0 to 5. RESULTS On the average the Vacurette was more painful (1.6 vs 1.1, p = 0.01). Vacurette biopsy was more effective than pipelle biopsy (64% vs 48%, p = 0.05). There was a significative difference of efficacity in the post-menopausal group (34% vs 13%, p = 0.05), but not in the pre-menopausal group (76% vs 64%, p > 0.05). When hysteroscopy diagnosed endometrial atrophy, there was no significative difference of efficacity (29% vs 23%, p > 0.05), whereas vacurette was significatively more effective when there was an other hysteroscopy diagnosis (78% vs 62%, p = 0.05). Both procedures were less effective in post-menopausal women (p = 0.001), and in case of endometrial atrophy (p = 0.001). CONCLUSIONS Both procedures were acceptable during ambulatory hysteroscopy. In our study, vacurette was more painful than pipelle. Vacurette was more effective but insufficient tissue for histologic evaluation was important in both procedures. This might be explained by the population included and the histologic method used.