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 half-a-kg are hooked to ventilators and other machines inside incubators. Children’s Hospital of Philadelphia, USA, 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 foetuses than newborns in hopes of giving them a better chance of survival. The researchers created a fluid-filled transparent container to stimulate how foetuses float in amniotic fluid inside mom’s uterus, and attached it to a mechanical placenta that keeps blood oxygenated. In earlystage animal testing, extremely premature lambs grew, apparently normally, inside the system for three-four weeks, the team reported on 25 April 2017.
“We start with a tiny foetus that is pretty inert and spends most of its time sleeping. Over four weeks we see that foetus opens its eyes, grows wool, breathes, swims,” said Dr Emily Partridge, a research fellow at the hospital and first author of the study published in Nature Communications. Human testing is still three-five years away, although the team is already in discussion with the US Food and Drug Administration.
Interestingly, hospitals attempt to save the most critically premature infants, those born before 26 weeks gestation and even those right at the limits of viability – 22 to 23 weeks. Extreme prematurity is a leading cause of infant mortality, and those who do survive frequently have serious disabilities such as cerebral palsy.
“The idea of treating preemies in fluid-like incubators may sound strange, but physiologically it makes sense,” says Dr Catherine Spong, an American foetal medicine specialist. One of the biggest risks for preemies is that their lungs aren’t ready to breathe air, she added. Before birth, amniotic fluid flows into their lungs, bringing growth factors crucial for proper development. When they’re born too soon, doctors hook preemies to ventilators to keep them alive but risking lifelong lung damage. The researchers’ goal is for the womblike system to support the very youngest preemies.