Volume of umbilical cord blood collection in the era of delayed cord clamping: a multicentre, prospective, feasibility study.

OBJECTIVES

To determine the percentage of adequate umbilical cord blood (UCB) collections defined as ≥70 mL of UCB after delayed cord clamping for 3 min was applied. Second, to correlate the UCB volume to gestational age at birth, birth weight and sex.

DESIGN

We conducted a multicentre, prospective, feasibility study in near-term infants delivered through caesarean section between November 2023 and December 2024. UCB was collected ex-utero, immediately after the placenta was removed from the womb.

RESULTS

A total of 195 UCB collections were attempted. In 11 cases (5.6%), the attempt failed due to rupture of the umbilical cord or damaged placenta by removal of the placenta from the uterus. The median volume of the remaining 184 UCB collections was 72 mL (IQR 56-86 mL). In only 54% (100/184), the UCB volume reached the target volume of ≥70 mL. We found that UCB volume was positively associated with birth weight (R2=0.0813, F(1181)=16.02, p value <0.001) but not with gestational age at birth (R2=0.0014, F(1181)=0.2553, p value=0.614).

CONCLUSIONS

A sufficient UCB volume (≥70 mL) was obtained in approximately half of the attempts. A higher birth weight was associated with a larger volume of UCB collection.