Children's Hospital of Philadelphia

For the first time, scientists have demonstrated an artificial womb that was able to successfully support fetal lambs at a developmental stage roughly equivalent to a 23-week-old human fetus.

The lambs were kept alive for four weeks in what its creators are calling "Biobags," translucent, flexible polyethylene bag-like structures filled with artificial amniotic fluid, in which oxygen is exchanged and wastes are removed as would occur in a biological uterus.

This womb could ultimately help treat one of the most complicated causes of infant mortality -- extreme premature birth.

Despite decades of efforts to reduce it, premature birth remains the leading cause of death among children under five years of age. And although medical science has pushed the edge of neonatal viability back to 23 weeks in the developed world, the course of treatment for such extremely premature infants is very complex, with a high risk of lifelong complications for the children who do survive.

What these babies need is more time in the womb. And the Biobag could provide them that precious time.

To be clear, the idea isn't to grow babies completely outside their mothers' wombs from conception to birth.

"I don't want this to be visualized as humans hanging on the walls in bags," lead study author and fetal surgeon Alan Flake told The Guardian. "This is not how this device will work or look."

Instead, Flake hopes the technology will provide a bridge that allows extremely premature infants more time to develop.

"If we can support growth and organ maturation for only a few weeks, we can dramatically improve outcomes for extremely premature babies," he said.

So far, the results are extremely promising. Premature infants are particularly vulnerable to respiratory failure and other complications from underdeveloped lungs, and the lungs -- and brains -- of the lambs in the experiment looked to have developed normally. The oldest lamb raised in the Biobag is now over a year old and appears healthy.

Lambs aren't human infants, and the device still has a way to go before it could conceivably reach the market. But Flake and his team are optimistic that the system could be in clinical trials within three years.

The best treatment for premature births is to prevent them in the first place. But for the cases where that isn't possible, the Biobag just might be the breakthrough that the tiniest of preemies need.

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