UNSW Embryology

Normal Development- Birth Placental Cord Clamping

© Dr Mark Hill (2008)

Acknowledgements

Introduction

In all placental mammals, the placental cord at birth undergoes changes which lead to the shut down of placental blood vesels and allow separation of placenta from the neonate. In humans, it is also typically clamped in two places prior to cutting the umbilical cord and the timing of this clamping is still a topical birth related issue.

Cord clamping after birth is considerered "early" if within the first 30 seconds and "delayed" if after 30 seconds. Early cord clamping may occur to prevent birth associated hemorrhage or for conditions that require immediate treatment of the neonate.

Newborn infant, showing one of the umbilical clamps.

With preterm infant births, there has been a recent Cochrane Review (2004) of the literature which concluded:

"Delaying cord clamping by 30 to 120 seconds, rather than early clamping, seems to be associated with less need for transfusion and less intraventricular haemorrhage. There are no clear differences in other outcomes."

Page Links: Introduction | Some Recent Findings | WWW Links | References | Glossary

Some Recent Findings

Levy T, Blickstein I. Timing of cord clamping revisited. J Perinat Med. 2006;34(4):293-7.

van Rheenen PF, Brabin BJ. A practical approach to timing cord clamping in resource poor settings. BMJ. 2006 Nov 4;333(7575):954-8.

Hutchon DJ. Delayed cord clamping may also be beneficial in rich settings. BMJ. 2006 Nov 18;333(7577):1073.

NCBI Bookshelf

Health Services/Technology Assessment Text (HSTAT) Bethesda (MD): National Library of Medicine (US), 2003 Oct.

Management of Preterm Labor
Management of Prolonged Pregnancy
Cesarean Childbirth
Vaginal Birth After Cesarean (VBAC) Volume 1 and Volume 2

References

PubMed

Levy T, Blickstein I. Timing of cord clamping revisited. J Perinat Med. 2006;34(4):293-7.
Rabe H, Reynolds G, Diaz-Rossello J. Early versus delayed umbilical cord clamping in preterm infants. Cochrane Database Syst Rev. 2004 Oct 18;(4):CD003248.

Articles

van Rheenen PF, Brabin BJ. A practical approach to timing cord clamping in resource poor settings. BMJ. 2006 Nov 4;333(7575):954-8.
Hutchon DJ. Delayed cord clamping may also be beneficial in rich settings. BMJ. 2006 Nov 18;333(7577):1073.

Search PubMed

Search jan 2007 "Placenta Cord Clamping" 70 reference articles of which 10 were reviews.

Search PubMed: term = Placenta Cord Clamping