Delayed cord clamping is when a baby’s umbilical cord is not clamped or cut until it has stopped pulsing or until the placenta has been delivered.
Immediately after birth, the cord pulsates as the placenta starts to deliver the volume of blood back to the baby. This can take less than a minute, several minutes, or more to complete after the baby is born.
A growing number of parents are choosing delayed cord clamping for their baby – some even believe in not severing the cord at all (known as lotus birth).
Parents who wish to delay or avoid cord clamping should plan with their clinical care providers prior to the birth. In the absence of any rare conditions or accidents at birth, parents have the right to consent to or refuse surgical intervention in a normal birth.
To aid communication, parents may choose to state verbally and in writing their refusal to consent to early cord clamping.
There is compelling evidence that refutes immediate cord clamping and supports delayed cord clamping as a safer birth practice.
Benefits of delayed cord clamping
The benefits of delayed cord clamping for the baby include:
- a normal, healthy blood volume for the transition to life outside the womb
- a full count of red blood cells, stem cells and immune cells.
For the mother, delayed clamping:
- keeps the mother-baby unit intact
- can prevent complications with delivering the placenta.
A review of large studies on delayed cord clamping showed the following benefits:
- higher blood pressure
- higher hematocrit levels
- more optimal oxygen transport and higher red blood cell flow to vital organs
- reduced infant anaemia
- increased duration of breastfeeding.
For very preterm infants, the benefits also included:
- fewer days on oxygen and ventilation
- fewer transfusions
- lower rates of intraventricular hemorrhage and late-onset sepsis.
Blood volume and fetal-to-neonatal transition
The importance of the baby’s blood volume relates to the fetal-to-neonatal transition at birth.
Before birth, the baby and placenta share a circulating blood supply that is separate to the mother’s. The placenta provides the baby with oxygen and nutrients, and clears waste, which is why a significant amount of the baby’s total blood volume is in the placenta at any given time. The blood circulating the placenta and cord is not ‘extra’ blood or waste – it belongs to the baby.
Immediately after birth, the cord pulsates as the placenta continues to provide essential oxygen and nutrients, and starts to deliver the volume of blood back to the baby. This transfer of blood is called placental transfusion and it can take less than a minute, several minutes, or more to complete after the baby’s born.
Placental transfusion is the system that provides the baby with red blood cells, stem cells, immune cells, and blood volume. Delayed cord clamping allows time for the placental transfusion, ensuring safe oxygen levels and blood volume in the baby.
Placental transfusion provides the baby with the volume of blood needed for the baby to transition from fetal life to ‘adult’ circulation and breathing. The perfusion of blood prepares the baby’s lungs to breathe, whilst providing an adequate number of red blood cells to then transport oxygen throughout the baby’s body.
Placental transfusion supports the newborn to rapidly increase the amount of blood sent to the lungs – this process expands the air sacs, clears fluid from the lungs, and keeps the lungs inflated. As the baby continues to receive blood from the placenta, this massive increase in blood flow to the lungs can take place without sacrificing blood flow to the other organs. Delayed cord clamping can ensure the baby has a sufficient blood supply for a safe fetal-to-neonatal transition.
How to delay cord clamping
In normal birth, delayed clamping is achieved by leaving the umbilical cord intact during the placental transfusion and not clamping until the cord has stopped pulsating.
Once the baby has begun to breathe and achieved a normal circulating blood volume, the cord ceases to pulse (cord appears white and flaccid). It can take around 3 to 7 minutes for a baby to transition and to establish a physiological blood volume, but this process can take longer for some babies.
In surgical deliveries (caesarean section), a ‘delay’ in clamping can be achieved (except in cases where there is incision or damage to the placenta). The baby can be held below the level of the placenta to assist with the transfer of blood from the placenta to the baby. The delay in clamping might be a minimum 40 seconds or even longer, depending on the circumstances of the birth. With a ‘lotus’ caesarean section the placenta may remain attached to the baby, without clamping the cord.
The World Health Organisation states the “optimal time to clamp the umbilical cord for all infants regardless of gestational age or fetal weight is when the circulation in the cord has ceased, and the cord is flat and pulseless (approximately 3 minutes or more after birth).”
Delayed cord clamping leaves the cord alone after birth and avoids disrupting the normal birth process.
While the cord is pulsating, placental transfusion is supplying the baby with oxygen, nutrients, and an increased blood volume to support the transition to life outside the womb.
Delayed cord clamping confers many benefits to the newborn baby including higher number of red blood cells, stem cells, and immune cells at birth.
- Buckley, S.J. “Leaving Well Enough Alone: Natural Perspectives on the Third Stage of Labor”, Gentle Birth, Gentle Mothering: A Doctor’s Guide to Natural Childbirth and Gentle Early Parenting Choices (2009) New York: Celestial Arts
- Mercer J. Current best evidence: a review of the literature on umbilical cord clamping. J Midwifery Womens Health 2001 Nov-Dec;46(6):402-14
- Mercer, J. et al, Delayed Cord Clamping in Very Preterm Infants Reduces the Incidence of Intraventricular Hemorrhage and Late-Onset Sepsis: A Randomized, Controlled Trial. Pediatrics Vol. 117 No. 4 April 1, 2006
- pp. 1235 -1242 (doi: 10.1542/peds.2005-1706)
- Mercer, J. Skovgaard, R. & Erickson-Owens, D. “Fetal to neonatal transition: first, do no harm“, Normal Childbirth: Evidence and Debate second edition (2008) edited by Downe, S. pp149-174
- Mercer, J. Skovgaard R. Neonatal transitional physiology: a new paradigm. J Perinat Neonatal Nurs. 2002 Mar;15(4):56-75. Review
- Hutchon, D. BSc, MB, ChB, FRCOG, Guideline for the management of Caesarean Section deliveries.
- WHO information sheet: “Optimal timing of umbilical cord clamping,” Essential delivery care practices for maternal and newborn health and nutrition.
– this article was kindly supplied by Kate Emerson, from www.cord-clamping.com
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