Optimizing umbilical cord blood collection: impact of obstetric factors versus quality of cord blood units.

Introduction: The main limitation factor for wide use of umbilical cord blood units (UCBs) as a source of hematopoietic progenitors for transplantation is cell dose. International standard guidelines recommend 2 x 10(7)/kg as the minimal nucleated cell dose for UCB transplantation for adults and 3.7 x 10(7)/kg for children. Therefore it is important to the optimize donor selection and the collection method so as to achieve high cell doses. In this study our main purpose was to determine whether obstetric factors influence UCBs collected.

Study Design: The study involved 304 UCBs collected from January to December 2004. The UCBs were collected after donor selection based on international criteria for cord blood banking. We analyzed UCB biological features such as collected volume, total nucleated cells (TNC), and CD34-positive cells, and obstetric factors.

Results: First, our study showed by multivariate analysis that infant weight was the main factor that influenced biologic features of UCB collected such as total volume (P = .000), TNC (P = .000), CD34 total count (P = .003), and CFU-GM (P = .004). Placental weight > 600 g produced a better volume (P = .007) and increased TNC (P = .056). Gestational age > 39 weeks enhanced CD34% (P = .016). Regarding route of delivery, we found that cesarean section produced higher volume and reduced WBC count compared to vaginal delivery, regarding cord length, it increased TNC (P = .037). And last, we noticed that female infants increased WBC (P = .013) and CD34(+) total count (P = .019) more than male ones.

Conclusions: Our results confirm that volume and TNC are influenced by several obstetric factors, such as greater infant and placental weight, predicting a better collection.