A cross-sectional study that included 100 units of umbilical cord blood (UCB) was conducted to evaluate the minimum criteria of cellularity in UCB units, according to NetCord standards at Instituto Nacional Materno Perinatal in Lima, Peru. The volume, total count of nucleated cells by hematological tests and total number of CD34+ as well as cell viability by flow cytometry were determined. The study revealed that 56% of UCB units do not fulfill the minimum criteria of cellularity to be cryopreserved in an umbilical cord blood bank. Furthermore, the UCB units of newborns who weighed more and were female had a higher volume and cell count. In conclusion, these variables must undoubtedly be considered to optimize the collection of UCB units and obtain greater cell counts that enable the storage of high-quality units in a future umbilical cord blood bank in Peru.