Researchers are creating an artificial womb to improve care for extremely premature babies - and remarkable animal testing suggests the first-of-its-kind watery incubation so closely mimics mom that it just might work.

Today, premature infants weighing as little as a pound are hooked to ventilators and other machines inside incubators. Children’s Hospital of Philadelphia is aiming for a gentler solution, to give the tiniest preemies a few more weeks cocooned in a womb-like environment treating them more like fetuses than newborns in hopes of giving them a better chance of healthy survival.

The researchers created a fluid-filled transparent container to simulate how fetuses float in amniotic fluid inside mom’s uterus, and attached it to a mechanical placenta that keeps blood oxygenated.

In early-stage animal testing, extremely premature lambs grew, apparently normally, inside the system for three to four weeks, the team reported Tuesday.

“We start with a tiny fetus that is pretty inert and spends most of its time sleeping. Over four weeks we see that fetus open its eyes, grow wool, breathe, swim,” said Dr. Emily Partridge, a CHOP research fellow and first author of the study published in Nature Communications.

“It’s hard to describe actually how uniquely aweinspiring it is to see,” she added in an interview.