The University of Sydney found that delaying umbilical cord clamping of babies born before 30 weeks reduces the relative risk of death or disability in early childhood.
The Australian Placental Transfusion Study is an award-winning and largest-ever clinical trial of delayed umbilical cord clamping of babies, conducted across 25 hospitals in seven countries.
The study compared outcomes for over 1500 babies from the initial study with 767 babies with caregivers aimed for the 60-second delay in clamping and 764 babies with caregivers aimed for cord clamping before ten seconds after delivery.
The study is published in The Lancet Child and Adolescent Health today and coordinated by the NHMRC Clinical Trials Centre at the University of Sydney’s in collaboration with the IMPACT Clinical Trials Network of the Perinatal Society of Australia and New Zealand and the Australian and New Zealand Neonatal Network.
Reducing the risk of death or major disability
Researchers found that delaying umbilical cord clamping reduces a child’s risk of death or major disability in early childhood by 17%. The data showed a 30% reduction in mortality before two years old.
Furthermore, 15% fewer infants in the delayed-clamping group needed blood transfusions after birth.
Study lead, Professor William Tarnow-Mordi, Head of Neonatal and Perinatal Trials at the Clinical Trials Centre and Professor of Neonatal Medicine, said that the simple process of aiming to wait a minute before clamping will have a significant impact worldwide.
“It’s very rare to find an intervention with this sort of impact that is free and requires nothing more sophisticated than a clock. This could significantly contribute to the UN’s Sustainable Development goal to end preventable deaths in newborns and children under five – a goal which has suffered during the pandemic,” he said.
“Applied consistently worldwide, aiming to wait a minute before cord clamping in very preterm babies who do not require immediate resuscitation could ensure that an extra 50,000 survive without major disability in the next decade.” said biostatistician Dr Kristy Robledo from the University of Sydney, who led the follow-up analysis.
“In other words, for every 20 very preterm babies who get delayed instead of immediate clamping, one more will survive without major disability.”
Why wait to clamp the umbilical cord?
Delayed umbilical cord clamping is routine in full-term babies to allow the newborn time to adapt to life outside the womb. Although until recently, clinicians cut the cord of preterm babies immediately to let urgent care begin.
“Ten years ago, umbilical cords were routinely clamped quickly after a very preterm birth and the baby was passed to a paediatrician in case the child needed urgent help with breathing,” said Professor Tarnow-Mordi. “But we now know that almost all very preterm babies will start breathing by themselves in the first minute if they are given that time. We think that, after delaying cord clamping, babies get extra red and white blood cells and stem cells from the placenta, helping to achieve healthy oxygen levels, control infection and repair injured tissue.”
How will this affect babies born today?
The study followed up with preterm babies for two years to understand the positive outcomes from cord clamping.
Co-author and founder of Miracle Babies Foundation Melinda Cruz said she hoped the results would give parents the confidence to discuss their options with their birthing professionals.
“I hope that prospective parents around the world will read about this trial for themselves and discuss it with their midwives and obstetricians,” she said.
The first evidence, published in the American Journal of Obstetrics and Gynaecology, found that delayed umbilical cord clamping might have benefits for preterm infants and their mothers came in 2017 from a systematic review of randomised trials in nearly 3,000 preterm babies.
The World Health Organization recommends that newborns and preterm babies who do not require positive pressure ventilation should not have their cord clamped earlier than one minute after birth; this has not always been consistently applied.
Steps going forward
“Midwives welcome this research – delaying cord clamping ensures that the physiological changes happening at the time of birth can happen and there are very good outcomes, especially for premature babies. We can all do this and now we know we should,” said Professor Caroline Homer, President of the Perinatal Society of Australia and New Zealand and past President of the Australian College of Midwives.
“Moving forward, it’s vital that perinatal professionals record the time of first breath and cord clamping to the second during births to allow for robust, large-scale data to further our work in this area.” said co-author Professor Jonathan Morris, Professor of Obstetrics and Gynaecology at the University of Sydney and Director of Women and Babies Research at The Kolling Institute.
“Intensive staff training in the new protocols will also be vital as it can be daunting to delay treatment in very early and sick babies, but the evidence suggests this results in the best outcomes for these children.”