Research and references
There's a huge amount of research around delayed and optimal cord clamping, so I've tried to split the research into categories. Hopefully this will help those of you working on student essays, projects and new research. Of course, it's important to note that these collections are by no means exhaustive literature reviews.
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Short overview of cord clamping
The practice of clamping the umbilical cord almost immediately following delivery can probably be traced to the introduction of oxytocics to reduce post-partum haemorrhage in the mother and fears of increased incidence of hyperbilirubinaemia in the baby. However changes in drugs available and more recent research 1-5 have rendered the approach of early cord clamping of no benefit in either respect.
There is a growing body of evidence showing that there are a number of very significant advantages for the newborn baby if clamping of the umbilical cord is delayed for three minutes or more following delivery 1-9. Delayed or deferred cord clamping (DCC) allows the baby to benefit from the continued supply of oxygenated blood from the placenta until spontaneous breathing is established 3,7, which can be of particular importance in the preterm neonate. It has been shown that if respiration starts before the cord is clamped then the risk of bradycardia is reduced10.
Following delivery, provided the umbilical cord is not clamped, there is a process of blood transfer from the placenta to the baby, known as placental transfusion. Research has shown that during the three minutes immediately after birth this transfusion can account for over 30% of the newborn’s blood volume 1-4,6. If deprived of this volume the consequences can be critical, with hypovolaemia and reduced cardiac output1,3,4,8, which can be of particular importance in babies with compromised cardiorespiratory function.
In pre-term babies lower blood volume in the baby increases the risk of intra-ventricular haemorrhage and a need for blood transfusion in the early stages, and late onset sepsis 1,2,4,8,9,11. In all babies there are also a number of longer term effects, such as anaemia and iron deficiency, lasting as long as 6 months 2-5. The deprivation of a significant volume of stem cells may also have implications on organ development and the spontaneous repair of any intra-partum injury 2. In addition to the shorter term benefits of delayed or deferred cord clamping, studies suggest that there are significant long-term effects, including a reduction in cognitive and behavioural problems 2,4.
An increasing number of national and international guidelines now recommend delayed or deferred cord clamping 10-12. However cardiorespiratory resuscitation and good early thermal management often remain a priority and thus prevent the practice of DCC in sick babies who are not considered suitable for “skin-to-skin” care. Preterm babies are likely to benefit most if clamping of the umbilical cord is delayed, yet these are the most likely to need resuscitation, making the provision of facilities to allow both these goals to be achieved together an important clinical need.
In summary, there are very significant benefits for the newborn if delayed or defered cord clamping is practised, particularly in pre-term babies, with a delay of at least 3 minutes but ideally waiting until the baby has made a the transition, and the advantages extend well beyond the immediate post-delivery period. It has been established that there is no disadvantage for the mother in this approach which in reality exactly matches nature’s own way.
Dr Alan Greene talks about the ticctocc campaign for optimal cord clamping. Click here to see the video.
1. Hutchon DJR. Immediate or early cord clamping vs delayed clamping. Journal of Obstetrics and Gynaecology, November 2012; 32: 724-729
2. Mercer JS, Erickson-Owens DA; Rethinking placental transfusion and cord clamping issues. J Perinat Neonat Nurs. 2012; 26; 3; 202-217.
3. Van Rheenen P. Delayed cord clamping and improved infant outcomes. BMJ. 2011; 343:d7127
4. Pan American Health Organization. Beyond survival: Integrated delivery care practices for long-term maternal and infant nutrition, health and development. World Health Organization. 2007.
5. Andersson O et al Effect of delayed versus early umbilical cord clamping on neonatal outcomes and iron status at 4 months: a randomised controlled trial. BMJ. 2011;343:d7157
6. Farrar D, et al. Measuring placental transfusion for term births: weighing babies with cord intact. BJOG. 2011; 118:70–75.
7. Wiberg N, Källén K, Olofsson P. Delayed umbilical cord clamping at birth has effects on arterial and venous blood gases and lactate concentrations. BJOG. 2008; 115: 697–703.
8. Rabe H, Reynolds G, Diaz-Rossello J. Early versus delayed umbilical cord clamping in preterm infants. Cochrane Database of Systematic Reviews.2004, Issue 4. Art. No.: CD003248. DOI: 10.1002/14651858. CD003248.pub2.
9. Mercer JS, et al. Seven-month developmental outcomes of very low birth weight infants enrolled in a randomized controlled trial of delayed versus immediate cord clamping. J Perinatology. 2010; 30; 11-16.
10. Richmond S, Wyllie J. European Resuscitation Council guidelines for resuscitation 2010. Resuscitation 81; 2010; 1389-1399.
11. Royal College of Obstetricians and Gynaecologists, UK. Clamping of the umbilical cord and placental transfusion. 2009. Scientific Advisory Committee Opinion Paper 14.
12. World Health Organisation. Guidelines on basic newborn resuscitation 2012. ISBN 978 92 4 150369 3.
13. Ceriani Cernadas JM, et al. The effect of early and delayed umbilical cord clamping on ferritin levels in term infants at six months of life: a randomized, controlled trial. Arch Argent Pediatr. 2010; 108(3); 201-208.