Errors in chromosome segregation during mitosis lead to aneuploidy (an abnormal number of chromosomes), which has deleterious or even lethal consequences for eukaryotic cells. In the yeast S. cerevisiae, aneuploidy is very often synonymous with growth defects; in humans, it contributes to cancer progression by promoting the emergence of advantageous or resistant clones. The fidelity of chromosomal segregation is therefore crucial for cells; however, the mitotic process is sensitive to the forces experienced by cells. Most cells proliferate in a confined environment, in both physiological and pathological conditions. Confined proliferation leads to the development of a mechanical, growth-induced, compressive stress, which is relevant to many pathologies such as cancer. How mitosis fares under mechanical pressure is still unknown, in particular when it comes to chromosome segregation and potential mechanically-driven aneuploidy.