The effect of early and late umbilical cord clamping on neonatal hematocrit

Objective: To compare the effect of early and late cord clamping (LCC) onneonatal hematocrit at 2 and 18 h of life.Study Design: In this double-blind randomized trial, 64 healthy full-term vaginally born neonates were randomly allocated to either early(30 s) or late (3 min) umbilical cord clamping. During the intervalbetween delivery and cord clamping, the attendant held the neonatesupine at the level of the introitus. Neonatal venous hematocrit wasmeasured at 2 and 18 h of life.Result: Neonatal hematocrit at 2 h of life (61 ±4.9 vs 61.6 4.5%) and18 h of life (56.9±4.1 vs 56.2±3.9%) was not significantly differentbetween the two groups. This was also true for neonatal polycythemia(20 vs 23.5%). In the LCC group, placental residual blood volume (PRBV)was 39.5% lower and estimated neonatal blood volume (ENBV) was 7.1%higher than that in the early cord clamping (ECC) group (P<0.001).Conclusion: Late cord clamping does not lead to a significant differencein the hematocrit level of the neonate or neonatal polycythemia, but isassociated with a significant increase in ENBV and a significant decreasein PRBV. Further trials should examine the effect of delaying cordclamping for a longer period of time or changing the position that theneonate is held in to determine whether these variations result in moreclinically significant results.Journal of Perinatology (2008) 28, 523–525; doi:10.1038/jp.2008.55;published online 3 July 2008Keywords: early cord clamping; late cord clamping; hematocrit;neonate; polycythemia