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



To compare the effect of early and late cord clamping (LCC) on neonatal 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 interval between delivery and cord clamping, the attendant held the neonate supine at the level of the introitus. Neonatal venous hematocrit was measured at 2 and 18 h of life.


Neonatal hematocrit at 2 h of life (61±4.9 vs 61.6±4.5%) and 18 h of life (56.9±4.1 vs 56.2±3.9%) was not significantly different between 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).


Late cord clamping does not lead to a significant difference in the hematocrit level of the neonate or neonatal polycythemia, but is associated with a significant increase in ENBV and a significant decrease in PRBV. Further trials should examine the effect of delaying cord clamping for a longer period of time or changing the position that the neonate is held in to determine whether these variations result in more clinically significant results.

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  1. Ibrahim HM, Krouskop RW, Lewis DF, Dhanireddy R . Placental transfusion: umbilical cord clamping and preterm infants. J Perinatol 2000; 20: 351–354.

    CAS  Article  Google Scholar 

  2. McDonnell M, Henderson-Smart DJ . Delayed umbilical cord clamping in preterm infants: a feasibility study. J Paediatr Child Health 1997; 33: 308–310.

    CAS  Article  Google Scholar 

  3. Lozoff B, Yimenez E, Wolf AW . Long term development outcome in infants with iron deficiency. N Eng J Med 1991; 325: 687–694.

    CAS  Article  Google Scholar 

  4. Mercer JS . Current best evidence: a review of the literature on umbilical cord clamping. J Midwifery Women Health 2001; 46 (6): 402–412.

    CAS  Article  Google Scholar 

  5. Rabe H, Reynolds G, Diaz-Rosselloy J . Early versus delayed umbilical cord clamping in preterm infants. Cochrane Database Syst Rev 2004; 18 (4): CD003248.

    Google Scholar 

  6. Van Rheenen P, Brabin BJ . Late umbilical cord-clamping as an intervention for reducing iron deficiency anemia in term infants in developing and industrialised countries: a systematic review. Ann Trop Pediatr 2004; 24 (1): 3–16.

    Article  Google Scholar 

  7. Mercer JS, Skovgaard RL . Neonatal transitional physiology: a new paradigm. J Perinat Neonatal Nurs 2002; 15 (4): 56–75.

    Article  Google Scholar 

  8. Jones JG, Holland BM, Hudson IR, Wardrop GA . Total circulating red cells versus hematocrit as the primary descriptor of oxygen transport by the blood. Br J Haematol 1990; 76: 288–294.

    CAS  Article  Google Scholar 

  9. Grajeda R, Preze-Eschamilla R, Dewey KG . Delayed clamping of the umbilical cord improves hematologic status of Guatemalan infants at 2mo of age. Am Clin Nutr 1997; 65: 425–431.

    CAS  Article  Google Scholar 

  10. Linderkamp O, Nelle M, Kraus M, Zilow EP . The effect of early and late cord clamping on blood viscosity and other hemorheological parameters in full-term neonates. Acta Paediatrica 1992; 81: 745–750.

    CAS  Article  Google Scholar 

  11. Yao AC, Moiniam M, Lind J . Distribution of blood between infant and placenta after birth. Lancet 1969; 762: 871–873.

    Article  Google Scholar 

  12. Fanaroff A, Mortin RJ . Neonatal-Perinatal Medicine: Disease of the Fetus and Infant, 7th edn. Mosby: New York, 2002.

    Google Scholar 

  13. Nelle M, Zilow EP, Kraus M, Bastert G, Linderkamp O . The effect of leboyer delivery on blood viscosity and other hemorheologic parameters in term neonates. Am J Obstet Gynecol 1993; 169 (1): 19–93.

    Article  Google Scholar 

  14. Ingomar CJ, Klebe JG, Baekgaard P . The transcapillary escape rate of T-1824 in healthy newborn infants. The influence of the placental transfusion. Acta Paediatr Scand 1973; 62: 617–620.

    CAS  Article  Google Scholar 

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The Research deputy of Mashad University of Medical Sciences financially supported this study. We thank Dezyani hospital of Gorgan midwives for their cooperation in the data collection and Mohammad Roshani for revising the paper.

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Correspondence to A Jahazi.

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Jahazi, A., Kordi, M., Mirbehbahani, N. et al. The effect of early and late umbilical cord clamping on neonatal hematocrit. J Perinatol 28, 523–525 (2008).

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  • early cord clamping
  • late cord clamping
  • hematocrit
  • neonate
  • polycythemia

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