The artificial womb environment reported in the journal Nature Communications is the result of almost four years of research and just as many prototypes.
Dr. Marcus Davey, one of the lead authors of the study, and a prominent figure in the area of Australian fetal research declared that the artificial womb developed at Philadelphia's Center for Fetal Research could significantly improve the outcome of premature births.
"If we can develop an extra-uterine system to support growth and organ maturation for only a few weeks, we can dramatically improve outcomes for extremely premature babies", Dr Flake says.
Researchers hope to one day use similar technology in humans to help the tiniest premature babies grow up healthy.
But that day isn't here yet. Those born at 23 weeks have a survival rate of just 15 per cent, but that goes up to 55 per cent at 24 weeks and 80 per cent at 25 weeks.
To circulate blood and oxygen, the researchers created a pumpless circulatory system that was connected to the umbilical blood vessels of the infant. Extreme prematurity refers to a baby who is born at or before 28 weeks of pregnancy.
"Our system could prevent the severe morbidity suffered by extremely premature infants by potentially offering a medical technology that does not now exist", Flake said. The limit of survival of premature human infants is about 22 to 23 weeks of gestation.
The discovery could have huge implications for those human babies born extremely premature, at between 23 and 28 weeks, a CHOP press release explains. The lamb's own heart pumps the blood through the umbilical cord into a gas exchange machine outside the bag.
Emily Partridge, a researcher at the Children's Hospital of Philadelphia, said in a video: "Just looking at them, it is immediately clear that they shouldn't be here yet". Stat also noted that the artificial uteri can easily be contaminated with infections, and the fetal heart is weak and sometimes can't handle artificially having blood pumped into it. It is a case of perfecting the artificial womb till even human babies can survive in it till maturity. Doctors said the lambs, which are now one year old, "appear to have normal development in all respects".
"That's the beauty of it, and why I'm optimistic we will improve on what is now done for extremely premature babies", he told journalists by phone.
Flake adds this level of extreme prematurity is the leading cause of infant mortality and morbidity in the USA, accounting for one-third of all infant deaths and one-half of all cases of cerebral palsy attributed to prematurity.
Though it could take another decade for the device to take a shape of reality, experts hope to procure licence for the device that could be used to support highly premature babies. Though scientists have come a long way towards sustaining the 30,000 premature babies born every year, early birth is still the primary cause of death among newborns. This means they are younger than 26 weeks.
The challenge is now to develop a version of the technology for human babies, which the team believes can be done in three to five years.
The Verge / Facebook While inside the bags, the lambs opened their eyes, had apparently normal breathing and swallowing movements and grew wool.