Scientists from Michigan to Japan have been working on artificial wombs for years in hopes of increasing the hundreds of thousands of preterm babies born each year. Now, researchers at the Children’s Hospital of Philadelphia (CHOP) have comerecreating an environment that could help more babies born extremely premature — between 23 and 28 weeks — thrive outside of their mother’s bodies. It’s already working for premature lambs.
Lambs make for an adequate experimental substitute for humans because their lungs develop similar to humans, and lung development is vital for premature infant survival. Results showed that their “extra-uterine device” could physiologically support lambs for up to four weeks. With the help of nutritional support, lambs on the system displayed normal physiological growth as well as lung and brain maturation.
Unlike past experiments, this one incorporated a pumpless oxygenator circuit connected to the lamb fetuses through an umbilical cord interface. The interface has a close “amniotic fluid circuit” that reproduces the environment of the womb. This is significant because pumps often overload underdeveloped hearts, which can be fatal. Ventilators, which can damage immature lungs, are not needed either. Instead, the fetus heart pumps blood via the umbilical cord into the systems external oxygenator that substitutes for a real placenta — except for no one is trying to eat this one after.
It’s important to note that this only extended the viability of fetuses to 23 weeks, and for the optimal odds of survival they need to reach 28 weeks. A lot more work needs to be done, but these findings are still promising. Past attempts at pumpless systems caused brain damage in animal subjects and only achieved a maximum duration of 60 hours. This system operated for up to 28 days or 670 hours, without the same questions. The CHOP team is breaking new ground and they predict incubation technology could be used on human babies within the next three years. Until then, these little lambs may hold more answers.