Mother of invention

Preemies’ artificial womb

Researchers are creating an artificial womb to improve care for extremely premature babies — and remarkable animal testing suggests the first-of-itskind watery incubation so closely mimics a mother’s womb, 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 a mother’s uterus, and attached it to a mechanical placenta that keeps blood oxygenated.

In early-stage animal testing, extremely premature lambs appeared to grow 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.

Human testing still is three to five years away, although the team already is in discussions with the Food and Drug Administration.

“We’re trying to extend normal gestation,” said Dr. Alan Flake, a fetal surgeon at CHOP who is leading the project and considers it a temporary bridge between the mother’s womb and the outside world.

Increasingly, hospitals attempt to save the most critically premature infants, those born before 26 weeks and even those right at the limits of viability — 22 to 23 weeks. Extreme prematurity is a leading cause of infant mortality, and babies who do survive frequently have serious disabilities, such as cerebral palsy.