The dataset consists of n=91 digital pathology whole-slide images (WSI) of endometrium carcinoma Pipelle biopsies, stained with hematoxylin and eosin (H&E) at Radboud University Medical Centers, Nijmegen (The Netherlands). The WSIs were scanned with a 3DHistech P1000 scanners at 0.25 um/px spacing, originally stored in MRXS file format. However, the WSIs made available here have been converted to TIFF format with a maximum spacing of 0.5 um/px. This was done to make slides broadly accessible (since MRXS files are sometimes not compatible with some digital pathology viewers or APIs). In order to fit into the Zenodo requirements, the 91 slides are compressed into a .rar file. Together with the data, we have released a web-based evaluation platform via the grand-challenge.org platform, which can be found at this link: https://endo-aid.grand-challenge.org/. In this way, researchers can download the WSI from Zenodo, process them with their algorithm to predict a single grading score for each slide, compile the predictions as indicated on the grand-challenge.org page, and submit them, to compare the results with the opinion of a panel of fifteen pathologists. The data is released under CC BY-NC 4.0 license