What is an “Artificial Womb”? A Response to Katy Faust and Samantha Stephenson

Katy Faust’s recent essay on artificial womb technology (AWT) sought to address the social and developmental impacts of AWT on children and families. The AWT that she is describing is referred to in the medical ethics literature as “complete ectogenesis” or full gestation outside of the womb. In her essay, Faust assesses the potential impacts of such AWT through the lens of her experience with emotionally starved infants at an orphanage in China, concluding that the potential harms of AWT could be substantially worse for children than parental abandonment. Her reasoning: abandoned children in the orphanage at least benefited from nine months of gestational development, while AWT would completely deprive children of the maternal-fetal bond. Faust buttresses her analysis with other examples of the commodification of children in the field of reproductive technology, including surrogacy, in vitro fertilization (IVF), and sperm donation.

Samantha Stephenson recently penned a similar reflection on how AWT could fuel further outsourcing of parental responsibility amid the growing availability of IVF and surrogacy. Like Ms. Faust, Stephenson considers the immense harm that the absence of maternal touch, voice, and affection could have upon a child developing in an artificial womb. She makes an important distinction between AWT as a means of rescue for premature infants and AWT used as a replacement for gestation. Should complete ectogenesis ever become a possibility, I think her discussion of the sociological and cultural implications will appear quite prescient. Humans have a natural drive to avoid pain and maximize pleasure, and the ability to outsource gestation would be undeniably attractive irrespective of the social consequences for the developing fetus.

Taken together, both essays underscore a fundamental problem in the commentariat’s analysis of emerging medical technology: neither essay focuses its analysis on the technology currently within the realm of scientific possibility. Complete ectogenesis remains in the realm of science fiction, and our current capabilities in medicine are years away from even attempting it. The AWT that is rapidly approaching human trials is artificial amnion and placenta technology (AAPT). AAPT would temporarily mimic some elements of the womb, such as providing oxygen and nutritional support to a neonate without forcing the neonate to breathe independently, but it could never replace gestation. Should the trials of AAPT prove successful, however, this technology will be a seismic change in the care of premature infants. At the same time, this technology will challenge the existing legal understanding of birth, fetal rights, and protections afforded to vulnerable patients who cannot advocate for themselves. Conflating AAPT with complete ectogenesis prioritizes speculative considerations over the immediate ethical concerns surrounding AAPT. Because of its immediacy, it is important to clarify what this technology is and what it is not.

The Looming AWT: Artificial Amnion and Placenta Technology

There are currently three main AAPT prototypes in various stages of development and animal trials: the VV preemie ECLS prototype (Michigan, USA), the Ex-vivo Uterine Environment (EVE; collaboration between the University of Western Australia and Tohoku University in Japan), and the Extra-Uterine Environment for Neonatal Development (EXTEND; Philadelphia, USA). Without belaboring the technical details, all three prototypes apply existing extracorporeal membrane oxygenation (ECMO) technology to fetal circulation in distinct ways. ECMO is commonly used across neonatal, pediatric, and adult intensive care to take over the physiologic functions of the lungs and/or the heart, providing oxygen to the blood outside the body and thereby relieving significant stress on those vital organs. Of the three prototypes, the EXTEND system (also known as the “Biobag”) has shown the most promise, sustaining fetal lambs at lower gestational ages for up to four weeks. The Biobag supplies ECMO support to the lamb’s heart and lungs via catheters placed in the umbilical arteries and vein while keeping the patient submerged in synthetic but sterile amniotic fluid.

The primary goal of the Biobag is to maintain fetal circulation outside the natural womb. That means that the patient inside continues to receive nutrition and oxygen through the umbilical cord rather than switching to breathing oxygen via the lungs (as typically occurs at birth). This allows the patient’s lungs to remain unexpanded and in their fetal state, protecting them from both premature developmental arrest and the trauma of mechanical ventilation in the neonatal intensive care unit (NICU). Premature arrest of lung development results in chronic lung disease of prematurity (CLD) and is a major cause of neonatal morbidity and mortality. Respiratory difficulties related to CLD can last throughout childhood and even into adulthood for many patients. AAPT could be a powerful tool to prevent these long-term complications.

So which premature infants does the Biobag seek to help? The target patient population for this technology is extremely premature infants (EPI) born between twenty-two and twenty-five weeks. This is the period in which EPIs face the highest risk of mortality and long-term disability, especially cerebral hemorrhages and subsequent cerebral palsy, but many survive with NICU support. These are also the infants most likely to develop CLD due to their severely underdeveloped lungs. In the Biobag animal trials, fetal lambs could be supported for up to four weeks, and these animal subjects had normal lung function and neurodevelopmental outcomes compared to their age-matched controls. Applying this technology to human subjects could allow us to support EPI for up to four weeks, thus permitting their lungs to continue developing without the trauma of transitioning from fetal breathing in utero to independent newborn breathing outside the womb.  

Ethical Debate Surrounding AAPT

As I noted before, conflating AAPT with other reproductive ethics overlooks the unique ethical challenges that AAPT will create. A proper understanding of the ethical landscape requires correctly categorizing reproductive technologies in the gestational process. To that end, Felix de Bie, one of the EXTEND researchers, provided a helpful analysis in the American Journal of Bioethics (figure reprinted under Creative Commons license). Using the de Bie framework below, we can see that reproductive technology such as in vitro fertilization clearly belongs to Domain I, while surrogacy and complete ectogestation would involve all four domains. The real area of interest for our purposes is Domain III. 

In Domain III, there are a few key debates surrounding AAPT as it moves closer to human trials. First, what is the nature of the patient supported by AAPT? Second, if there is a significant ontological difference between an AAPT patient and a traditional NICU patient, what are the respective rights and privileges afforded to each? Finally, how can this technology be ethically trialed with human patients? It is vital that we determine which patients would be selected for first-in-human trials and how to interpret the results of those initial studies given that the sickest babies are likely to be the first to receive AAPT support.

The first two areas of debate are closely related and the most hotly contested. Some (including me) view AAPT as a natural progression of other advances in newborn intensive care and believe that AAPT does not alter the nature of the patient it supports. Others believe that AAPT patients occupy a liminal space between unborn and born. Consequently, they have argued that AAPT requires creating a new category of human being between fetus and child, which they have dubbed the “gestateling.” Adopting the latter view not only requires developing a distinct set of rights and privileges for a “gestateling,” but it also requires a redefinition of birth. Birth, according to the United Nations, is defined as the following:

Live birth is the complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy, which after such separation, breathes or shows any other evidence of life, such as beating of the heart, pulsation of the umbilical cord or definite movement of voluntary muscles, whether or not the umbilical cord has been cut or the placenta is attached.

Advocates for creating a new state of being for AAPT patients have argued that birth more properly requires two components: birth-by-location (complete expulsion from the maternal womb) and birth-by-physiology (the rapid sequence of physiologic changes that occur after birth that allows a newborn to survive outside of the womb). As AAPT deliberately prevents birth-by-physiology from occurring (even if for the patient’s benefit), AAPT patients could not be considered born. Thus, the protections of legal personhood established at birth would not apply to them. Following the arguments for the redefinition of birth to their logical conclusions, it would be morally justifiable to allow the termination of an AAPT patient even after it has left the maternal womb.

Adopting this redefinition of birth ironically raises the distinct possibility of introducing abortion into the NICU even as we take a dramatic step forward in our ability to care for premature infants. On the other hand, this would also have significant implications for our ability to provide end-of-life palliative care in the NICU depending on where the patient is receiving care. If an AAPT patient is not born, then it would be permissible to “terminate” them in a state with permissive abortion laws. In that scenario, providing medically indicated palliative care may be prohibited in a state with restrictive abortion laws.

Using the de Bie framework, we can see that the fundamental issue is whether AAPT is a blending of Domain II and Domain III or Domain III with Domain IV. Those who view AAPT as a direct threat to abortion rights view it as the former; those who view AAPT as an expansion of traditional NICU medicine see it as the latter. Adopting the former view not only threatens to introduce a heated political debate into the NICU, but it also has significant implications for the practice of medicine more broadly. As I have argued in the Journal of Medical Ethics, there is no other instance in medicine in which a medical intervention performed on a patient alters that patient’s ontological status or rights. We should not allow AAPT to become the first.

While several technological hurdles remain between AAPT and human trials, the reality is that the age of artificial womb technology is probably upon us. Vitara Biomedical, the biomedical start-up company born from the EXTEND research group at the Children’s Hospital of Philadelphia, raised $135,000,000 in venture funding through its Series A and B offerings. Clearly, physicians, researchers, and investors alike recognize the promise of this technology. If incorporated ethically into clinical practice, AAPT could dramatically reduce morbidity and mortality for extremely premature infants. Ensuring that happens requires a precise understanding of what the technology is and the ethical and moral arguments being made about its use. It is vital that physicians and patients alike demand that bedrock concepts of the human experience like birth remain clearly defined and our most vulnerable patients remain protected. To that end, we must be clear-eyed about the unique ethical challenges that AAPT will pose.

Image by RFBSIP and licensed via Adobe Stock.