The simple idea that took 30 years to save thousands of babies

When a newborn baby is deprived of oxygen during birth, the damage to the brain does not happen all at once. Destructive processes can continue for hours and days afterwards, which gives doctors a narrow chance to intervene. The treatment developed by a University of Auckland research team is to lower the baby’s body temperature by a few degrees and keep it there while the brain begins to recover.

It does not sound like the kind of medical breakthrough that would take decades to establish. There is no futuristic machine doing something nobody can pronounce, and the central idea is familiar to anyone who has placed an ice pack on a swollen ankle. Cooling reduces inflammation and slows some of the pathways that cause cells to die, buying the brain time when time matters most.

The work has now earned the University of Auckland’s Fetal Physiology and Neuroscience team the $500,000 Prime Minister’s Science Prize. Mild cooling has become the only proven treatment for newborn brain injury caused by low oxygen, and is now used routinely in New Zealand and around the world. The judging panel said it had prevented severe disability or death for thousands of babies.

The simplicity came at the end, not the beginning. The research was co-led by Professor Laura Bennet and the late Professor Alistair Gunn, who began investigating therapeutic cooling alongside his mother, paediatrician and physiologist Professor Tania Gunn. Their early work produced evidence in animals that mild hypothermia could reduce brain injury, before the team moved cautiously through safety studies and international clinical trials.

The word cautiously matters because the first families who agreed to participate were being asked to trust an idea that had not yet been proven safe or effective. Their babies were critically unwell, the researchers were testing a treatment that challenged existing assumptions, and nobody could promise the outcome. Before his death in May, Professor Gunn said the prize also belonged to those families, whose trust allowed the research to begin properly.

The eventual protocol cools affected babies by only 2.5 to 3 degrees. That small change can suppress inflammation and interrupt several of the processes that cause brain cells to die after oxygen deprivation, reducing disability and improving quality of life for babies who survive. At least one million babies worldwide experience this kind of injury every year, which gives a few degrees of temperature an extraordinary amount of responsibility.

Science stories are often told backwards, beginning with the prize and trimming away the years when nobody knew whether the idea would work. By the time the treatment becomes standard care, the uncertainty has disappeared from the retelling and the breakthrough starts to look inevitable. It was not inevitable to the people beginning animal trials, building a cooling cap or asking frightened parents to place their trust in an unproven treatment.

It also did not belong to one dazzling moment. Professor Gunn described it as 30 years of work involving thousands of people around the world, and the team has continued refining the science rather than treating the current protocol as the final answer. The prize money will support research into how cooling affects the brain, whether it could help babies with milder oxygen deprivation and what might work for premature babies, for whom the existing treatment is often unsuitable.

Professor Bennet once met a boy who had been cooled during the team’s first safety trial. By then he was no longer the critically ill newborn she remembered from the research ward, but an energetic child running around the opening of the Liggins Institute while the adults watched him go.

After 30 years of trials, doubt and careful work, that is probably the clearest version of what the research achieved.