Eticur Germany GmbH, Munich, Germany.
Ludwig-Maximillians University Munich, Munich, Germany.
Stem Cells Transl Med. 2022 Jun 22;11(6):604-612. doi: 10.1093/stcltm/szac020.
Cord blood (CB) collected at birth has become a valuable stem cell source for hematopoietic stem cell transplantation (HSCT). However, the collection of umbilical cord blood always bears a risk of microbiological contamination, both in vaginal birth and in cesarean section. A total of 10 054 umbilical cord stem cell samples were successfully cryopreserved between 2010 and 2020, of which 783 (8%) samples were tested positive for bacterial contamination. Umbilical CB with a volume of less than 60 mL showed a bacterial contamination rate of 12%, and above 60 mL volume a rate of 6% was found demonstrating an inverse relationship between sample volume and contamination rate (correlation coefficient r = -0.9). The contamination rate was associated with the mode of delivery and showed a significantly higher contamination rate of 9.7% when compared with cesarean deliveries (1.4%). The 10-year period consistently shows an average contamination rate between 4% and 6% per year. It is conceivable that the inverse relationship between volume and contamination rate might be related to thinner veins although no scientific evidence has been provided so far. The lower contamination rate in cesarean sections appears to be related to the sterile operating setting. Overall, the rate of bacterial contamination varies and depends on the type of birth, the way of delivery, and probably the experience of the staff.
脐带血（CB）在出生时采集，已成为造血干细胞移植（HSCT）的宝贵干细胞来源。然而，无论是阴道分娩还是剖宫产，脐带血的采集都存在微生物污染的风险。在 2010 年至 2020 年期间，共成功冷冻保存了 10054 份脐带干细胞样本，其中 783 份（8%）样本检测出细菌污染阳性。体积小于 60mL 的脐带 CB 细菌污染率为 12%，体积大于 60mL 的污染率为 6%，表明样本体积与污染率呈反比（相关系数 r = -0.9）。污染率与分娩方式有关，与剖宫产相比，阴道分娩的污染率显著更高（9.7%）。10 年来，每年的平均污染率始终在 4%至 6%之间。可以想象，体积与污染率之间的反比关系可能与较细的静脉有关，但到目前为止还没有提供科学证据。剖宫产中较低的污染率似乎与无菌手术环境有关。总体而言，细菌污染的发生率不同，取决于分娩类型、分娩方式，可能还与工作人员的经验有关。
