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The application of mesenchymal (multipotent) stem (stromal) cells (MSCs) is one of the methods in current regenerative medicine, with main sources including bone marrow, adipose, and neonatal tissues like the umbilical cord. The umbilical cord matrix contains derivatives of post-embryonic mesenchyma, combining characteristics of mature and embryonic stem cells. However, MSCs irreversibly change during passaging, and there's no consensus on the number of passages before they lose multipotency. Some studies report significant morphophysiological changes at 2-3 passages, while others at 5-6 passages. Researchers analyzed over 300 umbilical cord samples, isolating mesenchymal cells using a combined mechanic-enzymatic method and culturing them in DMEM with supplements. The cells were passaged when reaching 70% confluence, and their state was assessed using an inverted microscope and FACS-analysis of MSC markers. The results showed that 10% of samples were excluded due to contamination, and 15% didn't yield cell cultures for unclear reasons. From 75% of umbilical cords, cells with fibroblast-like shape were obtained, which formed dense monolayers when reaching confluence. The study suggests that differences in cell state at various passages may be associated with individual characteristics of donor cells.