Scientists have announced that human trials for an artificial womb could be approved this year, giving hope to the 15 million babies born prematurely in the US each year.
A team from the Children's Hospital of Philadelphia successfully tested the uterus of premature lambs. They found that the animals “opened their eyes, became more active, and had apparently normal breathing and swallowing movements” while in the bag.
The main reason that half of premature babies do not survive is that their lungs are not fully developed due to premature birth, and they have difficulty transitioning from breathing in amniotic fluid to breathing in air.
The team conducted 300 successful tests and found that the animals had normal brain development and stable nutrition as if they were feeding from their mother.
The Food and Drug Administration (FDA) has met with experts to discuss the next steps to bring the artificial uterus, called EXTEND, into human trials – and will announce a decision later this year.
The artificial womb was tested on premature lambs (photo above on day four)
A baby is typically born between 37 and 40 weeks of pregnancy, but a premature baby is typically born at 28 weeks or earlier.
Most of premature babies' problems arise from lung immaturity, so the artificial womb tries to mimic the same environment the baby had before birth.
The artificial uterus works in two ways: first, by connecting the fetus's umbilical cord to an oxygenator, which circulates the blood and places it in a fluid sac, thus simulating the uterus and allowing the fetus to breathe and swallow amniotic fluid, as during pregnancy. development in the womb.
Emily Partridge and her team at the hospital used lambs because the majority of knowledge about human fetal development came from the lamb, including fetal circulation and developmental events.
The lambs were born between 106 and 113 days, the biological equivalent of the premature human infant of 23 to 24 weeks.
The experiments were successful with more than 300 lambs experiencing healthy development while in the artificial womb (photo above on day 28)
The typical gestation period for a lamb is 152 days.
Researchers reported that the test animals had a stable nutritional status at the end of their stay in the artificial womb, even though the lambs did not feed on a sheep.
Liver tests were positive and brain growth was normal.
“The animals showed normal or increased movement, sleep-wake cycles, intermittent breathing and swallowing and appeared generally comfortable and unstressed,” the researchers shared.
Partridge said her initial experiments with the premature lambs kept them alive and showed the animals developed healthy lungs, brains and other organs, prompting the FDA to consider approval to begin human trials.
“The idea is to bridge the rough patch when they're really struggling and push them through to a point where they can do well,” Partridge said in a video on EXTEND.
The artificial uterus connects an oxygenator to the fetus's umbilical cord and places it in a fluid bag so it can breathe by swallowing amniotic fluid, as in the womb
Alan Flake, one of the developers of EXTEND, clarified that the artificial uterus is not intended to replace pregnancy altogether.
He dismissed the possibility as “nothing more than a technically and developmentally naive, yet sensationally speculative, utopia” in The Journal of the American Medical Association in June, according NewScientist.
In September, the FDA held a meeting with more than 24 experts, including neonatologists, pediatricians and bioethicists, to discuss what steps should be taken to conduct a human trial.
At the meeting, Alan Flake, one of EXTEND's developers, said he believes the team's preclinical data is “sufficient to consider a carefully designed clinical trial.”
The FDA is expected to announce its decision later this year.
“One thing the project has taught me is to never give up,” Partridge said in the video. “You have to keep going, keep going until it works.”