To compare two different systems for optical coherence tomography for the diagnosis of cervical dysplasia and to assess potential benefits of three-dimensional imaging.OCT images were taken from unsuspicious and suspicious areas of fresh conisation specimens using two different imaging systems, one with the capability to produce three-dimensional images. All OCT images were separately evaluated by two blinded investigators based on a 6-grade classification (normal, inflammation, CIN 1, CIN 2, CIN 3, squamous carcinoma) and later compared to the corresponding histology. Sensitivity and specificity of OCT in detecting cervical dysplasia were determined.OCT images using both OCT systems were taken from 46 sites in ten conisation specimens and later compared to the corresponding histology. CIN lesions were diagnosed correctly by the two-dimensional OCT system with a sensitivity and specificity of 91% and 78% accordingly. Using the three-dimensional system sensitivity and specificity were 82% and 86% accordingly.Both OCT systems used were highly sensitive in identifying cervical intraepithelial neoplasia. Despite technical problems experienced in the present series, we believe that three-dimensional imaging has the potential to further improve the accuracy of optical coherence tomography.