24 Mar 2018

'Artificial womb' offers hope for premature babies

From Saturday Morning, 10:05 am on 24 March 2018

A baby’s first year is its toughest, but for premature babies even more so, with an increased risk of dying, or, for those who survive, subsequent health problems.

Researchers in the US hope new technology they are trialling could eventually help eliminate some of those risks.

Dr Marcus Davey

Dr Marcus Davey Photo: supplied

Dr Marcus Davey, a developmental physiologist and senior researcher, is part of a team researching pre-birth genetic disorders at the Centre for Fetal Research at the Children's Hospital of Philadelphia (CHOP).

The team is working on the development of an extra-uterine support device; a womb-like, fluid-filled environment that can give prolonged support of up to four weeks to extremely premature babies.

The device is called EXTEND (Extracorporeal Transitional Environment for Neonatal Development).

The team has been testing the device on lambs, which have a similar physiology to humans, and hope it could offer an alternative therapy for premature babies from 23 to 25 weeks old.

At present there are two ways to treat premature babies; palliative care and mechanical ventilators which provide oxygen.

Mechanical ventilation for a preterm infant is the “worst thing you can do for them,” says Davey.

“Any form of mechanical ventilation is un-physiological, but for preterm infants [whose lungs] are very fragile, it leads to further damage.”

He says that’s because the baby can’t get the oxygen in, and can’t get enough carbon dioxide out.

The ‘artificial womb’ would nurture the baby until it is at the cusp of viability at around 28 weeks, when independent breathing is possible.

In the team’s ‘artificial womb’ oxygen is regulated to a normal range and the foetus is nourished by fluid containing amino acids, dextrose and lipids - the three building blocks necessary to survive.

In the future the system may include maternal sounds that a foetus hears across the uterine wall, and which Davey describes as ‘gastric sounds.’ Adding this will give the researchers an indication of how such sounds affect blood pressure and heart rate.

Pre-term babies have blood pressure twice that of normal.

The team includes researchers specialising in the liver, heart and brain, and Davey says it will be important to look at these to examine any long term consequences of the system.

Davey anticipates EXTEND could be used on humans in the next three to four years.

Marcus Davey was a key speaker at the Perinatal Society of Australia and New Zealand annual congress in Auckland 25 to 28 March.