Given the task definition and input, reply with output. In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.

For a study published Tuesday in the journal Nature Communications, Partridge and other researchers from Philadelphia suspended premature lambs, a close animal model for human fetuses, in a liquid-filled, artificial womb, allowing them to further develop for four weeks—longer than in past similar attempts. 
  
 The researchers used eight lamb fetuses that were 105 to 115 days old—a level of development comparable to a 23-week-old human fetus. As they floated, the lambs’ brains and organs developed normally. The pinkish creatures opened their eyes, fattened up, and grew coats of white wool. 
  
 The researchers anticipate the animal studies will be completed within two years, and if approved, the wombs can be tested on human preemies within three to five years. 
  
 One reason preterm birth is so dangerous is that, for an underweight baby, the first few breaths of air halt the development of the lungs. “Infants that are currently born and supported in a neonatal intensive care unit with gas-based ventilation demonstrate an arrest of lung development,” Partridge says, “which manifests in a long-term, severe restriction of lung function.” 
  
 With the artificial womb, the infant would continue “breathing” through the umbilical cord as its floats in amniotic fluid, which would flow into and out of the bag. Using its tiny heart, the fetus would pump its own blood through its umbilical cord and into an oxygenator, where the blood would pick up oxygen and return it to the fetus—much like with a normal placenta. In addition to boosting lung growth, the amniotic fluid would protect the baby from infections and support the development of the intestines. 
  
 The babies who are hooked up to this apparatus would need to be delivered by C-section, as 60 percent of extreme preterm babies currently are. During the operation, the fetus would be given a drug that would prevent it from taking gulps of air during its brief brush with the outside world. Within seconds, it would be submerged again in the polyethylene bag, just like it was in the womb. 
  
 “I don’t want this to be visualized as fetuses hanging on the wall in bags,” said Alan Flake, a fetal surgeon at Children’s Hospital of Philadelphia and an author of the study, on a call with reporters. 
  
 He says it will look similar to a traditional neonatal incubator, potentially equipped with a camera to assuage anxious parents. The doctors could even pipe in the mother’s heartbeat. It’s “less stressful than seeing an infant on an incubator on an exposed bed,” Flake said. “That’s a very distressing environment for parents.” 
  
 Many hurdles remain in translating the lamb research to human babies. Artificial uteruses have been tried—and failed—before. A 1996 New York Times Magazine story declared “the artificial womb exists” and described a Tokyo lab in which baby goats floated in a heated, fake amniotic suspension. But, alas, it all ended in technical issues and circulatory failures. ||||| Fluid-filled ‘biobag’ allows premature lambs to develop outside the womb 
  
 Overcoming engineering, biology, and technology obstacles, a team of researchers has crafted what may be the best artificial womb yet: a fluid-filled bag in which lambs born early can live for up to 4 weeks, before being ushered into the outside world. Although others have designed similar systems that are still in animal testing, this one is notable for its stripped-down simplicity. 
  
 The result is a sealed “biobag” with one tube supplying artificial amniotic fluid and another draining it out. Although some lambs experienced complications, and human testing is, at best, several years off, the advance is generating excitement among those who care for pregnant women and their extremely premature babies. 
  
 “What they’ve got is a system where the fetus is really existing very much as it would in the mother’s womb,” says Anna David, a maternal-fetal medicine specialist at University College London (UCL). “The fetus knows what to do,” she adds, noting that as best they could, the physicians stepped aside and ceded control. 
  
 Fetuses are in a unique environment before birth. The placenta provides nutrients and oxygen, and the fetus’s lungs do not breathe air. They float in amniotic fluid, which is swallowed by the fetus and created by fetal urination; each day, the amniotic fluid “turns over” in this way. For babies that enter the world extremely early—as about 90,000 in the United States and Europe do each year—the prognosis can be grim, with survival ranging from 10% to 50%, and high rates of brain damage, lung disease, and other serious complications. 
  
 One of the biggest challenges is that the very technology that saves some of these premature babies, such as mechanical ventilation, also hurts them, for example by damaging their fragile lungs or halting lung development. In the past, researchers have tried to develop artificial wombs that mimic the prebirth environment, but these, too, have been intervention-heavy. In particular, they’ve relied on external pumps to push blood through an oxygenator circuit for gas exchange, which in turn can cause imbalances in fetal blood flow and lead to heart failure. 
  
 In the new study, reported today in Nature Communications , researchers at the Children’s Hospital of Philadelphia (CHOP) in Pennsylvania went through several iterations before hitting on technology that largely worked. Their final subjects were eight lambs delivered by cesarean section at about 110 days gestation—the equivalent of 23 or 24 weeks in humans, which is at the edge of viability. 
  
 The CHOP team, headed by fetal and pediatric surgeon Alan Flake, began with a high-tech version of a dumpster dive: collecting components doctors at the hospital no longer needed from a system called extracorporeal membrane oxygenation (ECMO). ECMO oxygenates the blood of critically ill infants and children. 
  
 For their first try, Flake’s group delivered several lambs shortly before they should have been born. The researchers bathed the lambs in artificial amniotic fluid, with electrolytes that mimicked the real thing, and connected the animals to an oxygenator. The goal was to see whether the system could sustain the lambs. The strategy worked unexpectedly well, with one animal surviving 108 hours, but sepsis and other complications made clear it wasn’t good enough. 
  
 Over months, Flake, along with fetal physiologist Marcus Davey, research fellow and surgeon Emily Partridge, and their colleagues kept tinkering. What they ended up with closely mimics biology: an approach that exchanges amniotic fluid rather than recirculating it, a sealed system to keep the outside world at bay, and a pumpless circuit for oxygenation of the blood that’s connected to the lamb fetus through the umbilical cord. The fetus’s heart drives circulation, which keeps blood pressure and other markers at normal levels. 
  
 After 4 weeks—the planned length of the experiment—the prematurely delivered lambs were taken off the system and put on artificial ventilators. By and large they did well, though with some modest complications including lung inflammation. Most were sacrificed for further study of how the artificial womb had influenced their development, but some were bottle-weaned, with the longest survivor now more than a year out. Flake is working with U.S. Food and Drug Administration to design an animal trial in accordance with the agency’s standards; he estimates that human testing is at least 3 years off. 
  
 If the new technology conjures up visions of The Matrix, with fields of fetuses growing in artificial wombs, Flake says that he’s not in the science fiction business: His goal is to help premature infants already being born, not push the limits of viability even earlier. “You go earlier [and] you’re very likely, in my mind, to open a can of worms,” he says. In part that’s because the system is just not designed to support even younger fetuses whose organs are more underdeveloped. Plus, trying to help them risks creating survivors with a poor quality of life—exactly the outcome Flake wants to avoid. 
  
 Experts are encouraged by the study. “This is just a much lower stress environment to support” the growth of premature babies than what’s offered now, says Tippi Mackenzie, a fetal and pediatric surgeon at the University of California, San Francisco, who trained with Flake but was not involved in the work. 
  
 There remain many uncertainties. One, Mackenzie says, is how fetuses battling an infection will fare in an artificial womb; infection is a common driver of preterm birth. Another is the long-term impact of an entirely new approach to caring for these babies. A clinical trial should closely track babies for some time, ideally a couple years, to assess how the system compares to the standard of care—not just in terms of survival, but in lingering health problems extremely premature babies can experience, says Neil Marlow, a neonatologist at UCL. 
  
 Despite the unknowns, “If it works, we should get on with it,” says Marlow, who like others agrees that the current setup for these children is far from ideal. “I think it’s just going to revolutionize [neonatal] care,” Mackenzie adds. “I don’t think that’s too much to say.” |||||

If placing super premature babies into fluid-filled bags sounds inhumane, consider that they are currently hooked up to invasive machines in sterile compartments with a survival rate around 50%, with many going on to struggle to do basic things like see, hear, walk, and talk. Researchers testing a new "bio bag" on premature lambs are finding surprising success, and hope that in the next decade or so human babies born on the very edge of viability—born after just 23 to 25 weeks gestation—might have a greater chance of survival in a womb-like environment, reports the Atlantic. They would be delivered via C-section and placed inside the bio-bag immediately after birth; a drug would prevent them from taking in any air after delivery (which is what halts lung development) and they would continue getting oxygen through their umbilical cords once inside the bio-bag. In the US alone, 30,000 babies are born "critically preterm," before 26 weeks, at a time so early in their development they are "not ready to be here," a research fellow at the Children’s Hospital of Philadelphia (CHOP) says. After multiple trials, a team at CHOP says they've hit on a system that closely mimics the womb, with a circuit driven by the fetal heart oxygenating the blood at normal levels through the umbilical cord, reports Science. The lambs in the trial continued developing normally in the bio-bags for up to 4 weeks, and one of them has now lived more than a year; more animal testing is in the works, with human testing at least three years away. Researchers say this isn't intended to deliver babies any earlier, but simply to give those born critically preterm a better chance—in a gentler environment—to survive. (Docs were able to keep this baby developing in his brain-dead mother's womb after a car accident.)