Meanwhile, special ventilation techniques for newborns and drugs to boost their lung function began to emerge, helping thousands of premature babies survive. ![]() At the time, many hospitals didn't even have intensive care units for sick newborns.īut in tests on premature lambs, those early oxygenators couldn't sustain the animals for long, for reasons that aren't entirely clear. In the following decade, scientists were eager to try the new technology on preemies after all, oxygenating blood outside the body is what the placenta does for the fetus. surgeons operating on an adult patient's heart successfully employed a heart-lung machine to externally oxygenate the patient's blood. The idea of an artificial placenta goes back more than half a century. While cautioning that more testing is needed before these technologies can be used in the clinic, he's impressed with the researchers' ability to think through all the processes needed to keep the fetus viable: “It's incredible." “It holds out a lot of hope for babies that are going to be born preterm," says David Weinberg, who heads the Human Placenta Project at the National Institute of Child Health and Human Development, in Bethesda, Md. Some bioethicists worry that opponents of abortion will seize on the speculative idea that artificial placentas could keep younger and younger preemies alive.īut researchers focus on the life-saving utility of this line of study. Other designs rely on novel technology that attempts to mimic the way the lungs breathe.Īs these devices move closer to clinical trials in humans, they're also raising a number of ethical questions about where the technology-and where our society-is headed. Some mimic the fetal environment by submerging the fetus in a fluid bath, which gets closer to the conditions of an artificial womb. His system is one of several designs under development around the world that aim to breathe for extremely premature babies. Now, after several recent breakthroughs, Mychaliska thinks his team's artificial placenta is only five years away from human trials. Mychaliska's team has been adapting existing technology to work reliably with the skinniest of blood vessels and developing materials compatible with the unique biology of fetuses. Building a breathing apparatus for a premature infant is not trivial, as the baby's tiny size and fragile physiology pose both medical and engineering challenges. Already, he's proven that it can sustain premature lambs for several weeks. If we want to save them… they may survive, but they likely will have varying degrees of lung disease from the treatment itself."įor more than a decade, Mychaliska has been working on a solution: an artificial placenta to keep extremely young preemies alive until they can breathe on their own. “We're in a catch-22 as baby doctors," Mychaliska says. ![]() Lungs simply aren't designed to breathe until the baby is close to full term, which is currently defined as 39 weeks, and even the gentlest techniques to assist breathing can damage the tissue. Of the survivors, many are left with long-term health problems. Although modern medicine can save many of them, the chances of survival for extremely small preemies-those younger than 28 weeks, barely in their third trimester-remain slim. Mott Children's Hospital, in Ann Arbor, he often sees premature babies who have left the womb too soon. As a fetal and pediatric surgeon at the University of Michigan's C.S. But George Mychaliska thinks that creating an artificial version of the placenta, or at least replicating its most important function, is in reach. There's still too much that scientists don't know about the early stages of development, when fetal cells grow into organs, limbs, and tissues. Re-creating everything that happens inside the womb belongs firmly in the realm of science fiction. Her oxygen flows seamlessly into the fetus's beating heart, brain, and limbs, and carbon dioxide from the fetus returns to the mother's blood, to be exhaled in her breath. Over a convoluted surface that grows large enough to cover a horse, fetal blood on one side soaks up oxygen from mom's blood on the other. The placenta starts to “breathe" for the fetus around 12 weeks in. Even before a woman knows she's pregnant, the placenta swells in size, poised to serve as the fetus's kidneys and liver until the fetus has its own. But that magnificent conversion would be impossible without the placenta, the life-giving organ that the developing fetus is tied to via the umbilical cord. The womb is home to the most complex feat of human biology: the transformation from embryo to fetus to baby.
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