Perth medical researchers working on artificial placentas for premature babies

Perth medical researchers working on artificial placentas for premature babies

Medical researchers at the Women and Infants Research Foundation (WIRF), based at Perth's King Edward Memorial Hospital for Women, are developing artificial placenta technology to support infants born at the border of viability. The project aims to provide a bridge for babies born between 21 and 24 weeks of gestation, allowing them to develop further before they must breathe and eat on their own.

For infants born this early, the challenges are significant. According to Professor Matt Kemp, chief scientist at WIRF, these babies often have fragile skin and lungs that are not well developed. He noted that babies born extremely early are frequently sick due to pregnancy complications, such as infections or placenta dysfunction, making them difficult to treat.

The proposed technology would allow babies to receive oxygen and nutrients in a manner similar to the uterus. Professor Kemp stated that the goal is to give these infants another three or four weeks to grow in an environment not dissimilar to where they came from, helping them transition to breathing room air.

Technology and Development

Unlike a natural placenta, the artificial version does not resemble a biological organ. Professor Kemp described it as two small, clear perspex blocks about the size of a Rubik's Cube connected to a bunch of catheters and hosing. The system is connected to the baby via the belly button.

A distinct feature of the WIRF system is that it is powered by the fetal heart rather than an external pump or pressure source. This allows the system to remain responsive to the specific needs of the fetus.

The research is currently being conducted using large animal models. Professor Kemp noted that sheep have long been used in obstetrics research to develop interventions such as antenatal steroids. The process begins in the Wheatbelt region of Western Australia, around Darkan and Collie, where livestock are sourced before being brought to the city for study. This international collaboration involves the University of Western Australia, Tohoku University Hospital in Japan, and the Nipro Corporation.

Timeline of Research Milestones

WIRF has spent nine years developing a high-efficiency gas exchange system. The progress of their trials in lambs is detailed as follows:

• 2016: Researchers achieved physiological maintenance in preterm lambs for one week, successfully transferring a lamb to pulmonary ventilation without infection.
• 2017: The healthy survival period was extended to two weeks.
• 2018: The team adapted the model to support extremely premature lambs (600g, equivalent to 23-24 weeks human gestation) for 120h.
• 2019: The research incorporated antenatal insults common in extremely preterm deliveries, such as inflammation and infection. WIRF reported being the only group to treat extremely preterm fetuses with chorioamnionitis for 120h.
• 2022-2023: The foundation became the first group to maintain extremely preterm fetuses for two weeks without cardiac failure.

Clinical Implications and Challenges

The foundation asserts that extremely preterm infants are a unique patient demographic requiring different treatment than older preterm infants due to their limited cardiovascular capacity and underdeveloped organs. Survivors of extreme preterm birth face elevated risks of blindness, learning deficits, cerebral palsy, cardio-pulmonary diseases, and infection.

Beyond survival, Professor Kemp described the technology as a bio-discovery tool. It allows researchers to study complex inputs from the placenta and maternal compartment to understand and optimize growth in preterm babies.

Despite these milestones, the technology is not ready for clinical use. Professor Kemp estimates that artificial placentas are at least 10 to 15 years away from being available in a neonatal intensive care unit (NICU). He explained that solving one set of problems often reveals others; for example, after resolving cardiac-related resistance in the circuits, researchers discovered a need for specific growth factors produced by the natural placenta to ensure normal fetal growth over long periods.