Hopes fluid-filled 'womb bag' will help baby born at 23 weeks to survive
Scientists in the US have developed a fluid-filled womb-like bag known as an extra-uterine support device that could transform care for extremely premature babies, significantly improving chances of survival.
In studies with lambs, the researchers were able to mimic the womb environment and the functions of the placenta, giving premature offspring a crucial opportunity to develop their lungs and other organs.
About 30,000 babies in the US alone are born critically early - at between 23 and 26 weeks of gestation, the researchers said.
At that age, a human baby weighs little more than 500g, its lungs are not able to cope with air and its chances of survival are low. Death rates are up to 70pc and those who do survive face life-long disability.
"These infants have an urgent need for a bridge between the mother's womb and the outside world," said Alan Flake, a specialist surgeon at the Children's Hospital of Philadelphia who led the development of the new device.
His team's aim, he said, was to develop an extra-uterine system where extremely premature babies can be suspended in fluid-filled chambers for a vital few weeks to bring them over the 28-week threshold, when their life chances are dramatically improved.
It could take up to another 10 years, but by then he hopes to have a licensed device in which babies born very prematurely are given the chance to develop in the fluid-filled chambers.
The team spent three years evolving its system through a series of four prototypes - beginning with a glass incubator tank and progressing to the current fluid-filled bag.
Six pre-term lambs tested in the most recent prototype were physiologically equivalent to a 23 or 24-week gestation human baby and were able to grow in a temperature-controlled, near-sterile environment, Mr Flake said.
The scientists made amniotic fluid in their lab and set up the system so that this flowed into and out of the bag.
Lung development in foetal lambs is very similar to humans, said foetal physiologist Marcus Davey, who worked on the team.
Mr Flake said the success of the system, details of which were published in the journal 'Nature Communications', was due to its mimicking life in the uterus as closely as possible.