How long to wait to clamp the cord?

Latest guidance on timing of cord clamping

What is optimal cord clamping? How long should the cord be left to pulsate? What is the recommended time for delayed cord clamping?

The answer to these questions of when to clamp the umbilical cord has become clearer. The Royal College of Obstetricians and Gynaecologists (RCOG) has recently published a Scientific Review Paper looking at the latest research and giving recommendations for practise.

Previously the RCOG had said the answer was '2 minutes or more, or until the cord stops pulsating'. Other organisations, such as various NHS trusts and the WHO (World Health Organisation) put delayed cord clamping as anything from 30 seconds to 3 minutes, with 'optimal cord clamping' defined as waiting one minute or more.

Confusing for parents and for practitioners.

Big recommendation from this paper is that timing of cord clamping should not be based on a number, but be about observation of the individual baby, and how they are transitioning to life outside the womb.

“The decision on timing to clamp the umbilical cord should be based on observations of the baby, its heart rate and breathing rather than a predefined interval after birth.” 

Through this paper, RCOG are recommending leaving the cord to continue to transfer blood to the baby helps with the transition.

Cutting the cord too soon could:

• Cause neonatal harm and death.

• Stop the baby getting their full complement of blood. About 33% of baby's blood is in the placenta. Leaving the cord to pulsate reduces that to 17%, giving the baby more blood.

  
  

• Reduce oxygen to the baby. Not just because the haemoglobin carries oxygen, but fetal haemoglobin (HbF) has "high oxygen affinity and releases oxygen more readily than adult haemoglobin (HbA) in response to a small decrease in arterial partial pressure of oxygen. This may be particularly important for its benefit during the minutes after birth before the neonate takes its first breath."

  
  

• Reduce the amount of stem cells, iron, and other nutrients getting to the baby.

• Cause bradycardia.

  
  

“Clamping the cord before sufficient lung aeration is achieved reduces the pre-load to the left side of the heart, which affects and reduces cardiac output, immediately leading to bradycardia in the newborn. In turn, this can lead to inadequate tissue perfusion as a newborn's shock response preferentially supplies vital organs at the expense of non-vital tissue.” 

What about premature babies?

Keeping cord blood flowing is particularly important for premature babies.

Research showed a 67% reduction in deaths of babies born under 34 weeks gestation when the cord was left for at least 2 minutes. Or put it another way, over 300% increase in deaths when the cord was clamped early.

What if the baby needs help?

Reviewing the research the paper recommends that preterm and term babies who may need resuscitation should be given "initial airway manoeuvres and inflation breaths with an intact cord for at least 2 min". This can be followed by cord clamping and further resuscitation on a resuscitation platform if still required. 

"Immediate cord clamping and removal of the baby to the resuscitation equipment may be unnecessary and make some babies worse."

Clamping at the placental end allows some blood in the cord to transfer to the newborn. This can be helpful in situations where a baby needs to be moved away for resuscitation, for example.

But what about a managed third stage and timing of injection?

Not a problem. A managed third stage is compatible with waiting. Research showed that the transfer of the artificial oxytocin across the placenta was very slow, so having the injection for the third stage can be done with the cord intact.

But what about the risk of PPH (postpartum haemorrhage)?

“Randomised controlled trials (RCT) have found no evidence that the timing of cord clamping affects PPH risk at vaginal or caesarean births.”

So should we wait till the cord stops pulsating?

This is sometimes given as a way to know that the blood has finished moving to the baby, however, this paper highlighted research that found blood flow may continue after the cord stops pulsating. The research found this could be four minutes - or more.

“The pulse is a pressure wave in the vessel wall, not in its content. ... recommended that pulsation should not be used to guide the time of cord clamping.” 

So waiting beyond the cord stopping to pulsate is recommended.

A better timing would be to 'wait for white', i.e. waiting until the cord turns from being purple in colour, and twisted, to white and untwisted, as the blood has gone.

The paper doesn't mention 'wait for white', just emphasises watching the baby.

Physiological based cord clamping

Rather than ‘optimal cord clamping’, which may be defined by a time, the paper used the phrase ‘physiological based cord clamping’. 

“PBCC is defined as clamping only after the infant has started breathing (or has received respiratory support) and the lungs have been aerated. No specific time is mandated.” 

This is more than just the first breath. It is when the baby is breathing regularly and steadily on its own, and the baby's physiological system has transitioned.

“In this paper, we wish to emphasise that cord clamping is a surgical procedure. As such, it must be justified on each occasion by an indication for action while the cord circulation is still functioning and the baby is transitioning from fetal to adult-type cardiorespiratory function.”

My thoughts:

This paper is not an opinion piece, but a recommendation for practice. It was written for obstetricians, other clinicians and policy makers.

I recommend all doulas have a copy in their bags, all antenatal teachers inform their clients, and all midwives and doctors move to get their local policies changed.

There are some things that are missing from the paper.

The paper exclusively talks about timing of cord clamping, not on birthing the placenta, so nothing on timing, environment, breastfeeding, or management of the birthing of the placenta when it needs help.

There is little mention of skin to skin, apart from that doing some resuscitation actions nearby is beneficial to keep the cord intact.

There is no mention of whether the cord needs to be clamped at all. No mention of cord burning or of Lotus birthing.

There is no mention of the parents of the baby in this paper. No mention of educating parents, sharing information, consent, or listening to the wishes of parents.

All that said, this is a very positive change for babies and families.

What do you think?

I am Cathy, Chilled Mama, a perinatal educator and trainer. (Perinatal = antenatal and postnatal.)

I support parents and practitioners.