The concept of creating an artificial womb that replicates the perfectly balanced conditions of a mother might seem unrealistic or maybe even impossible- but researchers from the Children’s Hospital of Philadelphia might just have achieved it.
The artificial womb, tested on prematurely born lambs, has been designed with the aim of supporting critically premature babies. The current system in place involves incubators, ventilators and all manner of machinery, in an attempt to imitate womb-like conditions to give premature babies a chance to develop normally. The limit of viability for newborn babies at present is 23 weeks; however, when born so early, would not be able to survive without medical assistance. Additionally, keeping these babies alive also carries risks – their lungs cannot efficiently absorb oxygen
yet, but at the same time, too much oxygen can result in blindness due to overgrowth of blood vessels in the eye, and too little will cause heart and brain damage. This is just one of the many risks for prematurely born babies, which also includes invasive, potentially hazardous surgery.
Whilst the current system is successful to an extent, the Children’s Hospital of Philadelphia has developed a much gentler, potentially safer method. It involves a transparent container called a BioBag – that could easily be mistaken for a large plastic bag – filled with an artificial amniotic fluid designed to mimic the important nutrients and chemicals in the mother’s womb. The premature lambs, born at the equivalent of the 23 week stage for humans, were sealed into the bag immediately following birth, and their still-intact umbilical cords were linked to a gas exchanger to provide them with oxygen and nutrients. Additionally, the environment of the BioBag was dark and temperature-controlled to more closely replicate the womb.
The results from the study were staggering, with images showing the development of the lamb foetuses from small, pink, sleeping creatures to ones covered in wool, able to open their eyes and breathe within 28 days of premature birth. Furthermore, the lambs showed normal development following growth outside of the BioBag – a year later, one of the lambs is living healthily on a Pennsylvanian farm following bottle-feeding by the hospital staff.
Whilst there is a long way to go yet in terms of pre-clinical research and further animal testing to refine this technique, if studies consistently remain this successful, researchers say this method may be set to enter human trials in the next few years. Currently, a baby born at 23 weeks has a 15% chance of survival, which quickly improves with each day the baby remains in the womb. Recreating a womb-like environment and essentially extending the gestation period in this way would be a huge leap forward in strengthening the chances of survival of these premature babies.