Growing up and getting stronger: improving the long-term health of premature babies

'Ventilators had some success, but a lot of the babies still died, and I wanted to know how to improve this process,' Professor Doyle says about his time as a trainee doctor at the Royal Women’s Hospital in Melbourne.

This story is part of our 10 of the Best - fourteenth edition. 10 of the Best is an annual NHMRC publication, showcasing 10 NHMRC-funded health and medical research projects. See more 10 of the Best.

A baby born before week 37 of pregnancy is a premature or pre-term baby.¹ Professor Doyle works predominantly with babies born before 30 weeks, who are called extremely preterm babies, and their families. These tiny babies often weigh less than 1000 grams.

Although those born extremely preterm who survive into adulthood mostly have good health, as a group they have higher rates of ill-health in many different areas.²

Professor Doyle 'wandered into the wilderness of research' after completing his clinical training in the late 1970s and started looking at the long-term impacts of various medical interventions in premature babies, from oxygen-enriched air to ventilators. 

Funding from NHMRC’s Centre of Research Excellence (CRE) scheme supported Professor Doyle and a multidisciplinary group of experts to improve techniques for helping newborn infants breathe, both immediately after birth and later, in the neonatal intensive care nursery. Many of these techniques are now incorporated into guidelines to support the breathing of babies around the world.

'Premature Babies had less than a 10% chance of survival before the 1970s, but today you see survival rates of more than 90%', Professor Doyle says.

The research team have also spent decades investigating the short- and long-term health of high-risk newborn infants, contributing to increased knowledge about interventions that may lead to adverse outcomes as these tiny babies grow into adults.

Funding over the last 15 years from NHMRC has allowed the team of experts to check in with babies born in the early ’90s as they progress into young adulthood.

'You have to be very patient,' Professor Doyle explains when reflecting on the long-term nature of his research. 

Now one of the most respected researchers in the field of paediatrics and child health globally, Professor Doyle says having the opportunity to help these children, and their families, has been the most rewarding part of his career. 

'Watching these tiny babies become young adults has been the best thing,' he says.

Including these children and their families in the research from the very beginning, is of critical importance to Professor Doyle.

The CRE in Newborn Medicine at Murdoch Children’s Research Institute was one of the first to include a consumer as an investigator on a grant application.

'We wanted to increase the involvement in our research of families and survivors themselves who have been born too early or too sick,' Professor Doyle says.

This enables the viewpoint of those most affected to help guide the research to answer the critical questions in the care of preterm babies and their families.

Professor Doyle is now supporting the next generation of researchers to continue these investigations and ask answerable questions. He says that with every question answered in research, more questions arise.

'The need for research is increasing exponentially.'

Next steps

While survival rates of those born extremely preterm have improved over the last 50 years, these babies have not yet reached later adulthood. Researchers will continue to follow tiny survivors of modern neonatal intensive care to understand what happens to their health after the first few decades.

'Although we are good at keeping infants born extremely preterm alive, they still have ongoing breathing problems in the nursery that lead to lung damage, with long-term adverse consequences for their breathing ability and for their brain function in later life,' Professor Doyle says.  

'Moreover, we need to understand better what it is about the brain that leads to higher rates of problems with thinking and movement in later life.'

The team are now conducting clinical trials to reduce lung and brain damage in the newborn, with the aim of improving respiratory and brain function in the long term.