Everything you need to know about artificial wombs

Artificial wombs are nearing human trials. But the goal is to save the littlest preemies, not replace the uterus.

Cassandra Willyardarchive page

September 29, 2023

https://www.technologyreview.com/2023/09/29/1080538/everything-you-need-to-know-about-artificial-wombs/

an umbilical tube connects a glass jar to a bag shaped like a large hot water bottle on the exam table at a medical center — Many research groups have been working on artificial wombs for years, including the Eindhoven University of Technology. They showcased this project in

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On September 19, US Food and Drug Administration advisors met to discuss how to move research on artificial wombs from animals into humans. These medical devices are designed to give extremely premature infants a bit more time to develop in a womblike environment before entering the outside world. They have been tested with hundreds of lambs (and some piglets), but animal models can’t fully predict how the technology will work for humans.

“The most challenging question to answer is how much unknown is acceptable,” said An Massaro, FDA’s lead neonatologist in the Office of Pediatric Therapeutics, at the committee meeting. That’s a question regulators will have to grapple with as this research moves out of the lab and into first-in-human trials.

What is an artificial womb?

An artificial womb is an experimental medical device intended to provide a womblike environment for extremely premature infants. In most of the technologies, the infant would float in a clear “biobag,” surrounded by fluid. The idea is that preemies could spend a few weeks continuing to develop in this device after birth, so that “when they’re transitioned from the device, they’re more capable of surviving and having fewer complications with conventional treatment,” says George Mychaliska, a pediatric surgeon at the University of Michigan.

One of the main limiting factors for survival in extremely premature babies is lung development. Rather than breathing air, babies in an artificial womb would have their lungs filled with lab-made amniotic fluid that mimics the amniotic fluid they would have had just like they would in utero. Neonatologists would insert tubes into blood vessels in the umbilical cord so that the infant’s blood could cycle through an artificial lung to pick up oxygen.

The device closest to being ready to be tested in humans, called the EXTrauterine Environment for Newborn Development, or EXTEND, encases the baby in a container filled with lab-made amniotic fluid. It was invented by Alan Flake and Marcus Davey at the Children’s Hospital of Philadelphia and is being developed by Vitara Biomedical.

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Other researchers are working on artificial wombs too, though they’re a bit farther behind. Scientists in Australia and Japan are developing a system very similar to EXTEND. In Europe, the Perinatal Life Support project is working on its own technology. And in Canada, researchers have been testing their version of an artificial womb on piglets. Researchers at the University of Michigan are working on similar technology intended to be used within preemies for whom conventional therapies aren’t likely to work. Rather than floating in fluid, the infants would only have their lungs filled. It’s a system that could be used in existing ICUs with relatively few modifications, so “we believe that that has more clinical applicability,” says Mychaliska,who is leading the project.

When will this technology be tested in humans?

The technology used in the EXTEND system has been tested on lamb fetuses, about 300 so far, with good results. The lambs can survive and develop inside the sack for three or even four weeks.

To move forward with human testing, the company needs an investigational device exemption from the FDA. At a meeting in June, Flake said Vitara might be ready to request that exemption in September or October. But at the September advisory committee meeting, when Flake was directly asked how far the technology had advanced he declined to answer. He said he could discuss timing with the advisory committee during the portion of the meeting that was closed to the public. To greenlight a trial, FDA officials need to be convinced that babies who try EXTEND are likely to benefit from the system, and that they’ll fare at least as well as babies who receive the current standard of care.

What would the first human tests look like?

The procedure requires a carefully choreographed transfer. First, the baby must be delivered via cesarean section and immediately have tubes inserted into the umbilical cord before being transferred into the fluid-filled container.

The technology would likely be used first on infants born at 22 or 23 weeks who don’t have many other options. “You don’t want to put an infant on this device who would otherwise do well with conventional therapy,” Mychaliska says. At 22 weeks of gestation, babies are tiny, often weighing less than a pound. And their lungs are still developing. When researchers looked at babies born between 2013 and 2018, survival among those who were resuscitated at 22 weeks was 30%. That number rose to nearly 56% at 23 weeks. And babies born at that stage who do survive have an increased risk of neurodevelopmental problems, cerebral palsy, mobility problems, hearing impairments, and other disabilities.

Selecting the right participants will be tricky. Some experts argue that gestational age shouldn’t be the only criterion. One complicating factor is that prognosis varies widely from center to center, and it’s improving as hospitals learn how best to treat these preemies. At the University of Iowa Stead Family Children’s Hospital, for example, survival rates are much higher than average: 64% for babies born at 22 weeks. They’ve even managed to keep a handful of infants born at 21 weeks alive. “These babies are not a hopeless case. They very much can survive. They very much can thrive if you are managing them appropriately,” says Brady Thomas, a neonatologist at Stead. “Are you really going to make that much of a bigger impact by adding in this technology, and what risks might exist to those patients as you’re starting to trial it?”

Prognosis also varies widely from baby to baby depending on a variety of factors. “The girls do better than the boys. The bigger ones do better than the smaller ones,” says Mark Mercurio, a neonatologist and pediatric bioethicist at the Yale School of Medicine. So “how bad does the prognosis with current therapy need to be to justify use of an artificial womb?” That’s a question Mercurio would like to see answered.

What are the risks?

One ever-present concern in the tiniest babies is brain bleeds. “That’s due to a number of factors—a combination of their brain immaturity, and in part associated with the treatment that we provide,” Mychaliska says. Babies in an artificial womb would need to be on a blood thinner to prevent clots from forming where the tubes enter the body. “I believe that places a premature infant at very high risk for brain bleeding,” he says.

And it’s not just about the baby. To be eligible for EXTEND, infants must be delivered via cesarean section, which puts the pregnant person at higher risk for infection and bleeding. Delivery via a C-section can also have an impact on future pregnancies.

So if it works, could babies be grown entirely outside the womb?

Not anytime soon. Maybe not ever. In a paper published in 2022, Flake and his colleagues called this scenario “a technically and developmentally naïve, yet sensationally speculative, pipe dream.” The problem is twofold. First, fetal development is a carefully choreographed process that relies on chemical communication between the pregnant parent’s body and the fetus. Even if researchers understood all the factors that contribute to fetal development—and they don’t—there’s no guarantee they could re-create those conditions.

The second issue is size. The artificial womb systems being developed require doctors to insert a small tube into the infant’s umbilical cord to deliver oxygenated blood. The smaller the umbilical cord, the more difficult this becomes.

What are the ethical concerns?

In the near term, there are concerns about how to ensure that researchers are obtaining proper informed consent from parents who may be desperate to save their babies. “This is an issue that comes up with lots of last-chance therapies,” says Vardit Ravitsky, a bioethicist and president of the Hastings Center, a bioethics research institute.

If the artificial wombs work, more significant questions will come up. When these devices are used to save infants born too soon, “this is obviously potentially a wonderful technology,” Ravitsky says. But as with any technology, other uses might arise. Imagine that a woman wants to terminate a pregnancy at 21 or 22 weeks and this technology is available. How would that affect a woman’s right to choose whether to carry a pregnancy to term? “When we say that a woman has the right to terminate, do we mean the right to physically separate from the fetus? Or do we mean the right not to become a biological mother?” Ravitsky asks.

With the technology at an early stage, that situation might seem far-fetched, but it’s worth thinking about the implications now. Elizabeth Chloe Romanis, who studies health-care law and bioethics at Durham University in the UK, argued at the advisory meeting that “an entity undergoing gestation outside the body is a unique human entity,” one that might have different needs and require different protections.

The advent of an artificial womb raises all kinds of questions, Ravitsky says: “What’s a fetus, what’s a baby, what’s a newborn, what’s birth, what’s viability?” These questions have ethical implications, but also legal ones. “If we don’t start thinking about it now, we’re going to have lots of blind spots,” she says.

Artificial womb

Figure from a 2017 *Nature Communications* paper describing an extra-uterine life support system, or “biobag”, used to grow lamb fetuses.^[1]

An artificial womb or artificial uterus is a device that would allow for extracorporeal pregnancy^[2] by growing a fetus outside the body of an organism that would normally carry the fetus to term.

An artificial uterus, as a replacement organ, would have many applications. It could be used to assist male or female couples in the development of a fetus.^[2] This can potentially be performed as a switch from a natural uterus to an artificial uterus, thereby moving the threshold of fetal viability to a much earlier stage of pregnancy.^[2] In this sense, it can be regarded as a neonatal incubator with very extended functions. It could also be used for the initiation of fetal development.^[2] An artificial uterus could also help make fetal surgery procedures at an early stage an option instead of having to postpone them until term of pregnancy.^[2]

In 2016, scientists published two studies regarding human embryos developing for thirteen days within an ecto-uterine environment.^[3]^[4] Currently, a 14-day rule prevents human embryos from being kept in artificial wombs longer than 14 days. This rule has been codified into law in twelve countries.^[5] According to The Washington Post, in 2021 “the International Society for Stem Cell Research relaxed a historical “14-day rule” that said researchers could grow natural embryos for only 14 days in the laboratory, allowing researchers to seek approval for longer studies. Human embryo models are banned from being implanted into a uterus”.^[6]

In 2017, fetal researchers at the Children’s Hospital of Philadelphia published a study showing they had grown premature lamb fetuses for four weeks in an extra-uterine life support system.^[1]^[7]^[8]

Components[edit]

An artificial uterus, sometimes referred to as an ‘exowomb^[9]‘, would have to provide nutrients and oxygen to nurture a fetus, as well as dispose of waste material. The scope of an artificial uterus (or “artificial uterus system” to emphasize a broader scope) may also include the interface serving the function otherwise provided by the placenta, an amniotic tank functioning as the amniotic sac, as well as an umbilical cord.

Nutrition, oxygen supply and waste disposal[edit]

A woman may still supply nutrients and dispose of waste products if the artificial uterus is connected to her.^[2] She may also provide immune protection against diseases by passing of IgG antibodies to the embryo or fetus.^[2]

Artificial supply and disposal have the potential advantage of allowing the fetus to develop in an environment that is not influenced by the presence of disease, environmental pollutants, alcohol, or drugs which a human may have in the circulatory system.^[2] There is no risk of an immune reaction towards the embryo or fetus that could otherwise arise from insufficient gestational immune tolerance.^[2] Some individual functions of an artificial supplier and disposer include:

Waste disposal may be performed through dialysis.^[2]
For oxygenation of the embryo or fetus, and removal of carbon dioxide, extracorporeal membrane oxygenation (ECMO) is a functioning technique, having successfully kept goat fetuses alive for up to 237 hours in amniotic tanks.^[10] ECMO is currently a technique used in selected neonatal intensive care units to treat term infants with selected medical problems that result in the infant’s inability to survive through gas exchange using the lungs.^[11] However, the cerebral vasculature and germinal matrix are poorly developed in fetuses, and subsequently, there is an unacceptably high risk for intraventricular hemorrhage (IVH) if administering ECMO at a gestational age less than 32 weeks.^[12] Liquid ventilation has been suggested as an alternative method of oxygenation, or at least providing an intermediate stage between the womb and breathing in open air.^[2]
For artificial nutrition, current techniques are problematic.^[2] Total parenteral nutrition, as studied on infants with severe short bowel syndrome, has a 5-year survival of approximately 20%.^[2]^[13]
Issues related to hormonal stability also remain to be addressed.^[2]

Theoretically, animal suppliers and disposers may be used, but when involving an animal’s uterus the technique may rather be in the scope of interspecific pregnancy.^{[original research?]}

Uterine wall[edit]

In a normal uterus, the myometrium of the uterine wall functions to expel the fetus at the end of a pregnancy, and the endometrium plays a role in forming the placenta. An artificial uterus may include components of equivalent function. Methods have been considered to connect an artificial placenta and other “inner” components directly to an external circulation.^[2]

Interface (artificial placenta)[edit]

An interface between the supplier and the embryo or fetus may be entirely artificial, e.g. by using one or more semipermeable membranes such as is used in extracorporeal membrane oxygenation (ECMO).^[10]

There is also potential to grow a placenta using human endometrial cells. In 2002, it was announced that tissue samples from cultured endometrial cells removed from a human donor had successfully grown.^[14]^[15] The tissue sample was then engineered to form the shape of a natural uterus, and human embryos were then implanted into the tissue. The embryos correctly implanted into the artificial uterus’ lining and started to grow. However, the experiments were halted after six days to stay within the permitted legal limits of in vitro fertilisation (IVF) legislation in the United States.^[2]

A human placenta may theoretically be transplanted inside an artificial uterus, but the passage of nutrients across this artificial uterus remains an unsolved issue.^[2]

Amniotic tank (artificial amniotic sac)[edit]

The main function of an amniotic tank would be to fill the function of the amniotic sac in physically protecting the embryo or fetus, optimally allowing it to move freely. It should also be able to maintain an optimal temperature. Lactated Ringer’s solution can be used as a substitute for amniotic fluid.^[10]

Umbilical cord[edit]

Theoretically, in case of premature removal of the fetus from the natural uterus, the natural umbilical cord could be used, kept open either by medical inhibition of physiological occlusion, by anti-coagulation as well as by stenting or creating a bypass for sustaining blood flow between the mother and fetus.^[2]

Research and development[edit]

The use of artificial wombs was first termed ectogenesis by JBS Haldane in 1923.^[16]^[17]^[18]^[19]

Emanuel M. Greenberg (USA)[edit]

Emanuel M. Greenberg wrote various papers on the topic of the artificial womb and its potential use in the future.^{[citation needed]}

On 22 July 1954 Emanuel M. Greenberg filed a patent on the design for an artificial womb.^[20] The patent included two images of the design for an artificial womb. The design itself included a tank to place the fetus filled with amniotic fluid, a machine connecting to the umbilical cord, blood pumps, an artificial kidney, and a water heater. He was granted the patent on 15 November 1955.^[20]

On 11 May 1960, Greenberg wrote to the editors of the American Journal of Obstetrics and Gynecology. Greenberg claimed that the journal had published the article “Attempts to Make an ‘Artificial Uterus'”, which failed to include any citations on the topic of the artificial uterus.^{[citation needed]} According to Greenberg, this suggested that the idea of the artificial uterus was a new one although he himself had published several papers on the topic.^{[citation needed]}

Juntendo University (Japan)[edit]

In 1996, Juntendo University in Tokyo developed the extra-uterine fetal incubation (EUFI).^[21] The project was led by Yoshinori Kuwabara, who was interested in the development of immature newborns. The system was developed using fourteen goat fetuses that were then placed into artificial amniotic fluid under the same conditions of a mother goat.^[21]^[22] Kuwabara and his team succeeded in keeping the goat fetuses in the system for three weeks.^[21]^[22] The system, however, ran into several problems and was not ready for human testing.^[21] Kuwabara remained hopeful that the system would be improved and would later be used on human fetuses.^[21]^[22]

Children’s Hospital of Philadelphia[edit]

In 2017, researchers at the Children’s Hospital of Philadelphia were able to further develop the extra-uterine system. The study uses fetal lambs which are then placed in a plastic bag filled with artificial amniotic fluid.^[1]^[8] The system consist in 3 main components: a pumpless arteriovenous circuit, a closed sterile fluid environment and an umbilical vascular access. Regarding the pumpless arteriovenous circuit, the blood flow is driven exclusively by the fetal heart, combined with a very low resistance oxygenator to most closely mimic the normal fetal/placental circulation. The closed sterile fluid environment is important to ensure sterility. Scientists developed a technique for umbilical cord vessel cannulation that maintains a length of native umbilical cord (5–10 cm) between the cannula tips and the abdominal wall, to minimize decannulation events and the risk of mechanical obstruction.^[23] The umbilical cord of the lambs are attached to a machine outside of the bag designed to act like a placenta and provide oxygen and nutrients and also remove any waste.^[1]^[8] The researchers kept the machine “in a dark, warm room where researchers can play the sounds of the mother’s heart for the lamb fetus.”^[8] The system succeeded in helping the premature lamb fetuses develop normally for a month.^[8] Indeed, scientists have run 8 lambs with maintenance of stable levels of circuit flow equivalent to the normal flow to the placenta. Specifically, they have run 5 fetuses from 105 to 108 days of gestation for 25–28 days, and 3 fetuses from 115 to 120 days of gestation for 20–28 days. The longest runs were terminated at 28 days due to animal protocol limitations rather than any instability, suggesting that support of these early gestational animals could be maintained beyond 4 weeks.^[23] Alan Flake, a fetal surgeon at the Children’s Hospital of Philadelphia hopes to move testing to premature human fetuses, but this could take anywhere from three to five years to become a reality.^[8] Flake, who led the study, calls the possibility of their technology recreating a full pregnancy a “pipe dream at this point” and does not personally intend to create the technology to do so.^[8]

Eindhoven University of Technology (NL)[edit]

Since 2016, researchers of TU/e and partners aim to develop an artificial womb, which is an adequate substitute for the protective environment of the maternal womb in case of premature birth, preventing health complications. The artificial womb and placenta will provide a natural environment for the baby with the goal to ease the transition to newborn life. The perinatal life support (PLS) system will be developed using breakthrough technology: a manikin will mimic the infant during testing and training, advanced monitoring and computational modeling will provide clinical guidance.^[24]

The consortium of 3 European universities working on the project consists out of Aachen, Milaan and Eindhoven. In 2019 this consortium was granted a subsidy of 3 million euros, and a second grant of 10 million is in progress. Together, the PLS partners provide joint medical, engineering, and mathematical expertise to develop and validate the Perinatal Life Support system using breakthrough simulation technologies. The interdisciplinary consortium will push the development of these technologies forward and combine them to establish the first ex vivo fetal maturation system for clinical use. This project, coordinated by the Eindhoven University of Technology brings together world-leading experts in obstetrics, neonatology, industrial design, mathematical modelling, ex vivo organ support, and non-invasive fetal monitoring. This consortium is led by professor Frans van de Vosse and Professor and doctor Guid Oei. in 2020 the spin off Juno Perinatal Healthcare has been set up by engineers Jasmijn Kok and Lyla Kok, assuring valorisation of the research done. More information about the spin off can be found here;^[25]

More information about the project of the technical universities and its researchers can be found here:^[26]

Weizmann Institute of Science (Israel)[edit]

Further information: Ectogenesis § Synthetic embryo

Electronically controlled ex utero roller culture system (technical steps during sEmbryo culture protocol)^[27]

In 2021, the Weizmann Institute of Science in Israel built a mechanical uterus and grew mouse embryos outside the uterus for several days.^[27] This device was also used in 2022 to nurture mouse stem cells for over a week and grow synthetic embryos from stem cells.^[28]^[29]

Philosophical considerations[edit]

Bioethics[edit]

The development of artificial uteri and ectogenesis raises bioethical and legal considerations, and also has important implications for reproductive rights and the abortion debate.

Artificial uteri may expand the range of fetal viability, raising questions about the role that fetal viability plays within abortion law. Within severance theory, for example, abortion rights only include the right to remove the fetus, and do not always extend to the termination of the fetus. If transferring the fetus from a woman’s womb to an artificial uterus is possible, the choice to terminate a pregnancy in this way could provide an alternative to aborting the fetus.^[30]^[31]

A 2007 essay theorizes that children who develop in an artificial uterus may lack “some essential bond with their mothers that other children have”.^[32]

Gender inequality[edit]

In the 1970 book The Dialectic of Sex, feminist Shulamith Firestone wrote that differences in biological reproductive roles are a source of gender inequality. Firestone singled out pregnancy and childbirth, making the argument that an artificial womb would free “women from the tyranny of their reproductive biology.”^[33]^[34]

Arathi Prasad argues in her column on The Guardian in her article “How artificial wombs will change our ideas of gender, family and equality” that “It will […] give men an essential tool to have a child entirely without a woman, should they choose. It will ask us to question concepts of gender and parenthood.” She furthermore argues for the benefits for same-sex couples: “It might also mean that the divide between mother and father can be dispensed with: a womb outside a woman’s body would serve women, trans women and male same-sex couples equally without prejudice.”^[35]

In popular culture[edit]

2023 – The movie The Pod Generation features detachable artificial wombs called pods. The Womb Center allows couples to share pregnancy more equally with pods.^[36]

FDA advisers discuss future of ‘artificial womb’ for human infants

By Jen Christensen, CNN

6 minute read

Updated 6:19 PM EDT, Tue September 19, 2023

https://www.cnn.com/2023/09/19/health/artificial-womb-human-trial-fda/index.html

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Scientists create artificial womb

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Independent advisers to the US Food and Drug Administration are meeting this week to discuss the regulations, ethics and possibilities of creating an artificial womb to increase the chances that extremely premature babies would survive — and without long-term health problems.

Although no such device has been tested in humans, similar ones have been used in a handful of cases to successfully develop animals. On Tuesday, during the first day of their two-day meeting, the advisers considered what human trials could look like.

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An artificial womb for humans would be a scientific advance that could help solve a major health problem. Preterm births are the No. 1 killer of children under the age of 5, according to the World Health Organization.

Because a baby’s lungs and brain finish developing late in pregnancy, a child born prematurely risks a lifetime of health problems including trouble breathing, gastrointestinal issues, vision and hearing problems, developmental delays and cerebral palsy.

Prematurity has become a growing problem in the US. The number of preterm births increased from 10.1% of all babies born in 2020 to 10.5% in 2021, according to the US Centers for Disease Control and Prevention. The issue disproportionately affects African Americans, who give birth prematurely at a rate that is 50% higher than those of White and Hispanic people.

An artificial womb is not designed to replace a pregnant person; it could not be used from conception until birth. Rather, it could be used to help a small number of infants born before 28 weeks of pregnancy, which is considered extreme prematurity. Less than 1% of babies are born this early.

The earlier an infant is born, the greater the risk of death. For example, only about 30% of infants born at 22 weeks survive, and just under 56% survive birth at 23 weeks, according to a 2022 study published in the journal JAMA.

The artificial womb could be able to help the baby develop further through those vital final stages when the lung and brain are developing. Like a person’s womb, it would deliver oxygen, nutrients and hormones.

Premature babies have to stay in a neonatal intensive care unit or NICU, where they can get special nutrition, extra care for their heart, help regulating their body temperature and help with their breathing.

NICUs are regularly successful in getting premature babies through the first part of their lives, but there’s always the danger of infection at a hospital. And if the baby needs to be put on a ventilator, it may injure their tiny lungs.

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Before the FDA would approve experimenting with a human in an artificial womb, scientists would have to show that the device could facilitate growth and development while reducing the rate of death and health problems, potentially compared with care with existing technology and techniques in a NICU.

The FDA’s Pediatric Advisory Committee is considering what kind of data scientists will have to show in such trials and what kind of regulations may be required, as well as what ethical considerations may need to be addressed. The committee also discussed what kind of metrics may be needed to determine the success of animal trials.

A handful of scientists have been experimenting with animals and artificial wombs. In each study, the artificial womb is constructed a little bit differently.

In a 2017 experiment, a group at the Children’s Hospital of Philadelphia was able to keep a developing lamb alive for 28 days in a sterilized plastic bag filled with fluid. Tubes that delivered amniotic fluid, medicine and oxygen were connected to the lamb’s umbilical cord tissue. The team saw positive growth and development in the lambs’ lungs, brains and gastrointestinal tracts.

“The technology is robust and stable,” Dr. Alan Flake, director of the Center for Fetal Research at the Children’s Hospital of Philadelphia, told the committee Tuesday. “We’ve now run over 300 lambs in the artificial womb, and the runs are generally remarkably smooth.

“We’ve observed no acute irreversible events that threatens survival,” he added. The “ultimate safety feature,” he said, is that the subject can be immediately removed and placed into standard care if necessary.

“We believe that our preclinical data supports feasibility and safety and that it’s adequate for consideration of a carefully designed clinical study of artificial womb technology,” Flake told the committee.

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The group hopes to try a device they’ve been testing named the Extra-uterine Environment for Newborn Development, or EXTEND, in humans.

In a trial of what scientists at the University of Michigan call an artificial placenta, lambs survived 16 days. The team saw positive results in the development of lung function and brain development until they were able to transition to mechanical ventilation.

In a presentation to the committee Tuesday, Dr. George Mychaliska, the Robert Bartlett Collegiate Professor of Pediatric Surgery at C.S. Mott Children’s Hospital at University of Michigan Health, said the group is working on a prospective study involving this work. They foresee using this artificial placenta with humans as a kind of “rescue therapy.”

However, “we recognize there are many ethical and regulatory considerations prior to clinical translation,” Mychaliska said.

In another experiment in Japan and Australia, in an artificial womb scientists call EVE, the lamb incubated for a week and had good development in the lungs, but there was some brain injury due to a technical issue.

Scientists at the University of Toronto used fetal pigs in it experiment with an artificial placenta in a trial modeled on the lamb experiments. Pigs and humans have a similar kind of umbilical cord, but there were problems with blood circulation and some heart issues in that experiment.

Despite the setbacks, Mike Seed, head of the Division of Cardiology at the Hospital for Sick Children in Toronto, thinks they are on the right track.

“We remain extremely enthusiastic about the potential of artificial womb technology and are about to embark on a new set of experiments using a third iteration of our circuit,” he told the committee.

The FDA committee agreed that before such technology could be used with humans, scientists would have to determine the most appropriate animal model to test the artificial womb.

Experts say there may also need to be a conversation about what viability — a concept referring to the ability of a human to survive outside the womb — means.

On Tuesday, the committee discussed at length the ethics of using the technology, including what conversations doctors may have to have with parents about how successful such an intervention could be if it’s tested on humans.

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The advisers also wanted to make sure that if humans were part of the trials, they would be inclusive. And they agreed that there would need to be extensive followup to determine what health effects, if any, children had in the long term.

Additionally, the committee discussed regulatory considerations and extra safeguards because trials would involve children, which by law requires extra steps to ensure safety. The advisers examined potential clinical considerations to fairly assess whether the new technology would be an advance over currently available care.

Although the two-day meeting can guide the way the FDA will move forward with regulating artificial wombs, the agency makes decisions on its own terms and does not have to follow the experts’ recommendations.

The first day of the meeting was open to the public, but the second day will be closed because the nature of the research involves proprietary information, the FDA said.