Neonatal Incubator or Artificial Womb? Distinguishing Ectogestation and Ectogenesis Using the Metaphysics of Pregnancy

A 2017 Nature report was widely touted as hailing the arrival of the artificial womb. But the scientists involved claim their technology is merely an improvement in neonatal care. This raises an under&#8208;considered question: what differentiates neonatal incubation from artificial womb technology? Considering the nature of gestation&#8212;or metaphysics of pregnancy&#8212;(a) identifies more profound differences between fetuses and neonates/babies than their location (in or outside the maternal body) alone: fetuses and neonates have different physiological and physical characteristics; (b) characterizes birth as a physiological, mereological and topological transformation as well as a (morally relevant) change of location; and (c) delivers a clear distinction between neonatal incubation and ectogestation: the former supports neonatal physiology; the latter preserves fetal physiology. This allows a detailed conceptual classification of ectogenetive and ectogestative technologies according to which the 2017 system is not just improved neonatal incubation, but genuine ectogestation. But it is not an artificial womb, which is a term that is better put to rest. The analysis reveals that any ethical discussion involving ectogestation must always involve considerations of possible risks to the mother as well as her autonomy and rights. It also adds a third and potentially important dimension to debates in reproductive ethics: the physiological transition from fetus/gestateling to baby/neonate.

Section 5 delivers a precise classification of ectogenetive technologies and their subjects. Section 6 considers consequences and ethical implications.

| EC TOG ENE S IS: IN CUBATI ON OR EC TO G E S TATI O N?
What is ectogenesis? Strictly speaking, the roots of the words "ecto" (outside) and "genesis" (development), suggests that this literally means "development outside"-i.e. outside the body. But since that is the norm in most of the biological world, the focus in practice is on the development of placental mammals 17 -specifically humans-outside the maternal body, where this development would normally happen inside.
A distinction is usually made between full and partial ectogenesis. 18 Full ectogenesis is the "babies in bottles" vision often espoused in science-fiction 19 : the complete development of a new human (or other mammalian) being outside the maternal body, from conception to babyhood. Partial ectogenesis is the partial development of new mammals outside the maternal body, where normally this development happens inside. In contrast to full ectogenesis, partial ectogenesis is both real and prevalent. IVF involves partial ectogenesis; the embryo initially develops in a petri-dish rather than a mammalian body. At the opposite end of the process, the neonatal incubation of preterm infants also involves partial ectogenesis: the 28-week-old, 1 kg preemie undergoes development for many weeks to come that normally happens inside the womb.
But if partial ectogenesis is already a reality, then why did the Nature report spark such controversy and feverish speculation? Why should an improvement in neonatal care call for special issues such as the present one? Indeed, why should we think that partial ectogenesis raises any special or new ethical questions at all, as opposed to just revisiting the questions that have become familiar in the wake of ongoing improvements in neonatal care over the past half century 20 -developments that have transformed the survival of extremely premature infants from sci-fi territory/curiosity 21 to routine medical reality? 22 What all of this suggests is that in the popular imagination, as well as much of the bioethical literature, there exists a difference between neonatal incubation and artificial gestation. But if we take that seriously, then what people mean by "ectogenesis" cannot merely be the development outside the body that normally happens within, as we defined it earlier. It must (also) be a kind of development outside the body that is in some way relevantly different from neonatal incubation. What, then, is this? Perhaps it is development inside an artificial womb, as opposed to in an incubator. But that just leads us to the following question-what makes something an artificial womb as opposed to a neonatal incubator?
There is a mix here of genuine question and mere linguistic confusion. The latter is easily dealt with: let ectogenesis be a general term for mammalian development outside the maternal body, where this normally happens within. Thus both IVF and the neonatal incubation of premature infants 23 genuinely involve (partial) ectogenesis. Let ectogestation be the term for whatever it is that people want to pick out when they differentiate between neonatal incubation and what they think of as "genuine" artificial gestation (be it full or partial). 24 The genuine, and under-considered, 25 question before us, then, is to spell out what makes something ectogestation rather than just ectogenesis. Setting other important social and ethical questions aside-which no doubt will be discussed elsewhere in this volumethis will be the focus of the current paper. And our contention is that spelling out this difference requires that we consider the nature-or metaphysics-of pregnancy.

| ROMANIS ON DIS TING UIS HING ARTIFI CIAL WOMB TECHNOLOGY VS . IN CUBATI ON
But first we shall consider a proposal by Romanis 26 that distinguishes between what she calls "artificial womb technology" (AWT) and neonatal intensive care (NIC). Her analysis is a step in the right direction, but as we shall see is insufficient to grasp fully the difference between ectogenesis and ectogestation.  But not of term infants-who can also reside in a NICU. 24 Murphy op. cit. note 14 also explicitly notes a difference between "extracorporeal gestation" and "mere ectogenesis" (i.e. in IVF). But she fails to tell us what the difference is. Note, though, that on her view ectogestation need not be artificial; we might achieve it by implanting human fetuses in pigs. We would be inclined to call this xenogestation rather than ectogestation. 25  But surely, the effects on human interaction are much more complicated than Romanis lets on here. The fetus in utero may not be able to see or touch others, nor be seen or heard. But it is constantly touching the maternal body from the inside, and is hearing and experiencing, through her, some of her social network. The neonate, by contrast, may be seen as well as heard, but it is residing in hospital and therefore is mostly isolated from the maternal body (which it can now only touch from the outside)-and almost completely isolated from its (future) social environment. Things are different again for the gestateling, which in the current set-up does not feel or taste the maternal body at all, nor has any access to her wider social world. 35 Romanis deserves credit for identifying the right questions, but falls short of providing answers. This is not surprising. To actually understand these issues (or so we submit), we need to understand the under-considered nature of gestation and birth.

| THE ME TAPHYS I C S OF PREG NAN C Y: DIS TING UIS HING FE TUS E S AND NEONATE S
What is the metaphysics of pregnancy, or the nature of gestation?
What are the entities involved in this process? How do they relate to each other? And how do these questions differ for similar entities that have a different reproductive biology, such as a bird sitting on, or an embryo developing in, an egg? Given both the common and mundane nature of pregnancy as an essential part of the mammalian life cycle, and its highly unique aspects-the physical intertwinement of what might be considered two separate individuals-it is truly astonishing that no more attention in philosophy or bioethics has been paid to these questions.
In recent work Kingma has begun to address them, focusing on the metaphysical relationship between the fetus and the pregnant organism. 36  35 Sedgwick (op. cit. note 9) imagines a "wearable" artificial womb which allows a gestateling-unlike a neonate in a NICU-to be taken home and "worn." In this vision the gestateling experiences much of the social embedding of a fetus in utero-although not its direct physiological interaction with the maternal body. Developments are underway to make the Nature technology "parent friendly" and will allow the gestateling e.g. to more general question about the nature of pregnancy in the context of distinguishing ectogestation from neonatal incubation-as we shall do in this paper. Our claims and arguments are therefore compatible with, but not reliant on, the truth of Kingma's parthood view.
What we do directly take from Kingma is the more general idea that contemporary Western culture fosters an understanding of pregnancy Kingma labels the fetal container model: a tendency to depict, speak of and imagine fetuses as already separate, individuated "babies" that are incubated in pregnant women. 38  If this claim is correct, then it suggests an explanation for why so little progress can be made on differentiating ectogenesis from ectogestation. For according to the fetal container model there is nothing more to pregnancy than the incubation of an already separate individual-a baby-inside the womb. 41 If gestation is nothing more than incubation, then neonatal incubation already is ectogestation; there is no room for a gap here. And birth, on this view, is a mere change of environment; 42 the only difference between neonates and fetuses is their location. This leaves no room for treating an extra-corporeal gestateling "as if it had never been born," 43 nor for saying how such a gestateling, ontologically, is more like a pre-viable fetus rather than a neonate.
But the fetal container model is highly misleading; our instinctive judgment that there is a difference between neonatal incubation and ectogestation indicates correctly that there is more to gestation A 39-week-old fetus, about to emerge into healthy, screaming babyhood, is much more developed-physically, physiologically and cognitivelythan a 24-week, 600 gram preemie, barely clinging on to life in a top-level NICU. Yet the latter is classed as a neonate-albeit a very immature onewhereas the former is undeniably a fetus (even though it will become a baby very soon). There appears to be a difference between neonates and fetuses that cuts across linear progressive development which is not captured by viability alone; and-if there is a difference between incubation and ectogestation-is not just a matter of location either.
Kingma's parthood view gives us one way of understanding this difference: fetuses are body parts; neonates are not body parts. 44 But we need not accept that claim to appreciate that fetuses and babies have a very different physiology. Most obviously, fetuses do not breathe but oxygenate their blood via the placenta. This results in different normal arterial and venous oxygen tensions compared to neonates; requires a different kind of hemoglobin; and so on. It also necessitates a completely different cardiovascular set-up: the fetal heart functions as a single (rather than, in neonates, a double) pump; and the cardiovascular system in fetuses compared to neonates has multiple shunts, different flow rates and blood pressures in different parts of the system, and so on. 45 We tend to overlook these physiological differences, because the cultural fetal container model conditions us to forget about them, teaching us to view the fetus merely as a baby-within. But these differences are well known in medicine and are of profound relevance to fetal-maternal and neonatal specialists. They explain why, sometimes-for example in placental malfunction-fetuses are in great peril inside, but absolutely fine as soon as they are delivered. This is because they have difficulty performing certain physiological requirements of gestation, but no difficulty performing the physiological requirements of babies. The opposite also happens; some 38 Kingma, op. cit. note 36; Kingma argues that this cultural understanding drives the metaphysical "containment view" (see previous footnote). But the cultural understandings and metaphysical claims should be kept distinct. Our general cultural conviction that tables exist and persist-for example-may drive a metaphysical commitment to their existence, but is still compatible with a wide range of precise metaphysical views on the existence and persistence of tables.  Ibid: 614. 41 The cultural incarnation of this view has perhaps reached its most evident extreme in how our practices construe surrogate pregnancy: an embryo or "baby" is created by two gametes-and then implanted (for incubation) in a surrogate mother: "Here, we find Which surrogate mother it is appears to be rather irrelevant; this womb or that-or even an artificial incubator-any womb will do as long as the baby is seen to be safely "housed." pregnancies can be wholly uncomplicated, only for birth to reveal that this baby cannot, or struggles to, perform certain physiological requirements of babies that weren't required for fetal physiology.
Think of lung-problems, heart defects, etc.
There is thus a difference in normal physiological set-up between fetuses and neonates that is much more profound than location alone. We can quibble over the precise ontological weight we should assign to this difference. 46 But we can all agree that it is a much more substantial difference than either location or gestational age alone.
Thus, very roughly, to be a fetus is to have a physiology characteristic of a fetus; and to be a neonate is to have a physiology characteristic of a neonate. To be a gestateling, then, is to have a physiology characteristic of a fetus, but to exist outside of a gestating mammal.
Once we appreciate that, it is immediately obvious that fetuses and neonates also have different physical characteristics. The fetus, to be precise, has an entire organ that the neonate lacks: a placenta.
It also has an umbilical cord, an amnion and chorion, and-or so we argue-an additional body-cavity, filled with amniotic fluid. The neonate has none of these, for these parts were shed at or around birth. and an internal physiological transformation that includes changes to vasculature, heart, lungs, hemoglobin, etc. Some of these (e.g. cardiovascular changes) happen near-instantly at or around birth; others (e.g. moving to mature hemoglobin) take longer.

| DIS TING UIS HING EC TOG ENE S IS AND EC TOG E S TATION-AND FURTHER CON CEP TUAL CL ARIFIC ATIONS
How can all of this deliver a distinction between ectogenesis and ectogestation? Remember that Romanis 52 attempted to provide such a distinction but did not succeed because she did not tell us University Press) terms, should we consider "fetus/gestateling" and "neonate" to be distinct substance sortals, picking out distinct entities? If so, there is no numerical identity between fetuses and neonates; newborn mammals were never fetuses but begin at birth. Or should we consider them phase sortals, picking out the same entity at different phases of life, comparable to "adolescent" and "adult," or "caterpillar" and "butterfly"? Note that on either view using one sortal rather than another conveys useful information: a fetus/gestateling has a placenta-whether real or artificial-whereas a neonate does not. Equally only butterflies-not caterpillars-have wings. The present discussion is compatible with either a phase or substance understanding of these terms, and Romanis does not specify what sort of "ontological similarity" she has in mind. We leave a proper discussion of such matters for a different time (see also Kingma (2018), op.
cit. note 37). 47 See also Kingma (in press), op. cit. note 37 for this terminology and a discussion of different views on the fetus and its boundaries. 48 This "extra-embryonic material" motivates some to consider the "division" of the early embryo into "embryo proper" and "extraembryonic material" as a further logical division puzzle, alongside (the possibility of) twinning (e.g. Burgess, J. (2010). Could a zygote be a human being? Bioethics, 34, 61-70). No such puzzle arises if the placenta is part of the fetus, as we argue. (After all, no one considers such a problem to arise because the embryo forms-say-a kidney.) One might then wonder what the relation is between the placenta and the gestator? Well, if, following Kingma, op. cit. note 35, the fetus is part of the gestator, then all of the fetus' parts, including the placenta, will also be part of the gestator. This is due to the transitivity of parthood-if a is part of b, and b is part of c, then a is part of c. If the fetus is not part of the gestator, then the placenta, which is built from mostly fetal tissue but incorporates some maternal tissue too, may, for example, be considered a site of overlap, with either all or part of the placenta being part of both gestator and fetus. Or it could be argued that, upon incorporation into the placenta, the maternal-origin tissue ceases to be part of the mother. Any such claims would require further defense.  analysis of the nature of pregnancy in the previous section allows us to answer all of these questions in detail.
First, gestatelings are treated as if they had never been born, not in the sense that they haven't left the maternal body-for they have-but in the sense that they haven't undergone the transition from a fetal physiology to a neonatal physiology. Thus they are only "born" in the sense that they have changed location from inside to outside the maternal body, i.e. "born-by-location-change".
But they are not "born" in the sense that they have changed their physiology from fetus to neonate, i.e. "born-by-physiology-change." 53 Second, this specifies the way in which gestatelings are "more ontologically similar" 54 to fetuses than neonates: they retain fetal physiology (as they have not undergone the "born-by-physiology-change" from fetus to neonate). Third, the relevant way in which neonates behave more independently than gestatelings is that, however much supported, they operate on the physiological blue-print of a neonate, which is almost entirely independent from maternal physiology, as opposed to a fetal physiological blue-print, which is (normally) entirely dependent on and integrated in maternal physiology. 55 Finally, and this is the fourth point, our analysis elucidates how development during gestation "is distinct from 'continuing to develop after being born.'" 56 Not in the sense that one is creative where the other is not-which is vague-but in the sense that one involves developing on a fetal physiological blue-print-or, we might say as a fetus/gestateling-whereas the other involves developing on a neonatal physiological blue-print-or, we might say, as a neonate/baby.
In combination this delivers the contrast we seek: between ectogenesis and ectogestation. Incubators, as a non-ectogestative version of ectogenetive technology, support neonates, taking over, or assisting with, functions they cannot yet perform. They do so on the physiological blue-print of a "born-by-physiology-change" (as well as ''born-by-location-change") neonate. Ectogestative technologies, by contrast, support gestatelings; they take over, or assist with, functions that cannot be performed on the physiological blue-print of a fetus. Ectogestation-and here is our rough definition-is thus development after being "born-by-location-change" but before being "born-by-physiology-change": i.e. development outside the maternal body that prevents the physiological transformation from fetus to neonate.
With this clearer understanding of the difference between ectogenesis and ectogestation-and between fetuses, gestatelings and neonates, regardless of gestational age-we are in a position to make further conceptual distinctions that may help to clarify future discussion on these topics.
First, using Romanis' 57 helpful terminology, we should distinguish fetuses, gestatelings and neonates. Fetuses and gestatelings (however much supported) are not yet "born-by-physiology-change," and have fetal physiology and characteristics; neonates, by contrast, are "born-by-physiology-change," and have neonatal physiology and characteristics-again, however much supported. Gestatelings share with neonates, in contrast to fetuses, that they are "born-by-location-change"-and hence reside outside rather than inside the maternal body. We agree with Romanis that it is helpful to clearly distinguish these categories because the terms "neonate" and "fetus" each carry connotations that are not, or are only sometimes, applicable to gestatelings. Conversely, if the gestateling is not a body part (or if it is not relevant that it is a body part), then the ethics of gestatelings and fetuses, whatever their cognitive, physiological and developmental similarities, will always be different because one-but not the 53 In ordinary birth, of course, both of these happen pretty much simultaneously. Which one of these truly defines "birth" when they come apart is not a question we settle here.
Note that this question does seem to arise; in a Dutch public panel on ectogestation a member of the public asked: "would these babies have two birthdays?" (Schalij, op. cit. note 34). 54 Romanis, op. cit. note 16. Note that Romanis, in this quote, spoke of similarity between the gestateling and the pre-viable fetus (our emphasis). But we think the emphasis of this claim must be about similarity to fetuses, not about pre-viability. For it is difficult to see why, say, a 39-week-old gestateling (if we were to create one) would be more similar to a pre-viable fetus than to a viable fetus. We consider "pre-viable" to be a slip caused by the focus on very premature lambs, as well as Romanis' focus on the as-yet unrealized possibility of keeping alive fetuses/gestatelings before what is now considered the "viability threshold." 55 Kingma (in press), op. cit. note 37. 56 Romanis, op. cit. note 16.  We are grateful to an anonymous reviewer, whose suggestion we are developing in this paragraph.
other-must involve consideration of the gestator's autonomy. Either way, carefully bearing in mind the relevant differences between gestatelings, fetuses and neonates is essential for the quality of these and other ethical debates.
Second, we can distinguish between different extracorporeal support systems. We already distinguished the more general category of ectogenesis, including neonatal incubation and IVF, from its more specific subset: ectogestation. But we can make further distinctions amongst ectogestative technologies. For consider again the Nature report. 60 Its system is extracorporeal and maintains fetal physiology: it runs blood out of the umbilical cord through a pump-free oxygenator, and suspends the gestateling's body in amniotic-like fluid. Cardiovascular set-up and oxygenation happens on the blue-print of a fetal physiological system. We therefore concur with Romanis 61 -and contrary to what the scientists themselves implied in various press statements-that this is definitely an ectogestative technology; not mere incubation. Butand here we separate from Romanis-this does not mean it is the provision of an artificial womb. Instead it is the provision of engineered replacements for parts of the fetus/gestateling's body. Just as a kidney dialysis machine replaces, or takes over, the function of kidneys; and just as a bionic leg replaces the leg; the reported technology replaces the placenta and amniotic sac. The womb itself is not replaced; the "lamb-in-a-sack" is most like a free-floating fetus in its artificial amnion. Hence a more apt label would be: artificial amnion and placenta technology (AAPT).
Setting physical and technological possibility aside, we can conceive of different kinds of ectogestative technologies that replace fewer of the fetus/gestateling's body parts. We could conceive of a technology that, instead of using a biobag, leaves the actual amnion/chorion intact. All that would be replaced is the placenta. Or we could imagine leaving the placenta intact (which probably means removing the gestator's womb, or part of the womb, as well as the fetus); what then could be replaced would be the maternal circulation, perhaps via a combination of heart-lung and kidney-dialysis machine that feeds the major arteries and veins serving the placenta/ womb on the maternal side. Perhaps such technologies would more appropriately be called artificial wombs-though really they would not be artificial wombs either, but something more like partial artificial gestational bodies.
We should pause here to ask why the artificial womb is such an alluring concept when of all the things that can be replaced-amniotic sac, placenta, maternal circulation and/or vascular interface-the womb itself is actually of least interest. 62 Why then do we find it so tempting to think of, and present, these technologies as artificial wombs as opposed to artificial fetal organs? Again this is neatly explained by the cultural dominance of the fetal container model. This conditions us to think of pregnancy as incubation; as providing a house-a womb-a container!-in which resides a free-floating baby (a pink one, without funny parts). This gives us only one way in which to frame, report and understand ectogenetive scientific developments: as the beginning of the "artificial womb." This, in turn, results in an understanding and reporting that reinforces that fetal container model. Given how much the fetal container model leads our thinking astray, we would do well to break the cycle. It would be both helpful, as well as scientifically and metaphysically more accurate, to put the term "artificial womb" to rest and to speak of ectogestation (as opposed to ectogenesis) in its place, and of the more specific technology at stake: artificial placenta; artificial decidua; artificial amnion; etc. First-what are the ethical implications? These rarely follow directly from any metaphysical analysis. 64 On the one hand, many conceptual and ethical questions that supposedly derive from ectogestation may actually just be generic to all ectogenetive technologies. If, for example, ectogestation pushes forwards the limits of viability or significantly improves survival and lowers the risks of premature birth, then that is relevant for ethical decision-making.

| CON CLUDING REMARK S
But the relevant questions would be affected just as much if other forms of ectogenesis-such as neonatal incubation-had these effects. And, indeed, our recent history shows that improvements in neonatal incubation do have such effects. 65 Second, we also submit that the details of ethical questions are likely to depend much more on the actual technological abilities afforded by any particular system, rather than on the type of technology that it is. As we argued, the Nature system is genuinely ectogestative.
That remains true even if for technological reasons, the technology could only ever be used on-say-26-week-old preemies. That would leave the seemingly paradoxical situation that 23-26-week-old preemies need to be-and remain-incubated as neonates (assuming, plausibly, that having transitioned physiologically to a neonate, there is as yet no way back), whereas 26+-week-old preemies can be ectogestated as fetus/gestatelings. But this only seems paradoxical if one expects too much from one distinction; it emphasizes once again that progressive linear human development is cross-cut by the distinction between neonates, fetuses and gestatelings. Equally the relative actual safety profiles of different systems will have much more significant ethical consequences-for example affecting maternal decision-making in premature onset of labor-than the type of system it is.
Third, we want to revisit an observation by Romanis that AWT, unlike neonatal incubation, is "almost entirely non-invasive. Support mechanisms surround rather than aggressively invade the gestateling." 66 According to our analysis, this is incorrect-or at least misleading. The recent technological developments are invasive ones: they remove and replace entire fetal organs (the placenta, amnion, etc.) and invade main (umbilical) veins and arteries. Now this invasion may well be "less stressful and painful for the developing human," 67 and less disturbing to its physiology, than neonatal incubation. It may also be the case that-where artificial oxygenation is only done in cases of impending miscarriage-the placenta and amnion were about to be lost anyway. Invasiveness alone does not have direct ethical consequences. Even so it is important to be precise, particularly if we were to consider ectogestation for reasons other than impending miscarriage/premature birth. It may then matter ethically that such a technology does invade the fetus/gestateling. Fourth, our analysis foregrounds another aspect of invasiveness that is morally relevant but tends to be underappreciated: on the gestator's body. In the view outlined, ectogestation (as opposed to incubation) involves the preservation of fetal physiology.
But since birth is not (just) a change of location, but also a physiological transition, successful ectogestation requires that this physiological transition from fetus to neonate is prevented from happening. Almost certainly this requires a caesarean section, 68 to prevent a physiological transition from being triggered by the actual birthing process: the expulsion via the vagina. Put more vividly: successful ectogestation almost certainly requires what is, effectively, a fetal transplant rather than a birth. And this requires invasive medical action on the maternal body. 69 This is the one aspect of ectogestation that clearly does raise ethical issues that do not apply to neonatal incubation: any ethical discussion involving ectogestation must therefore always involve considerations both of the woman's bodily autonomy/rights and of possible risks to her health and wellbeing. 70 This is relevant to moral analysis tout court, but especially-again-if use of ectogenesis is suggested for reasons other than impending premature birth.
Fifth, the fuller and more nuanced understanding of gestation, ectogestation, fetuses and birth offered in this paper could improve speculation-as that is all it can currently be-about possible trajectories towards full ectogenesis. Partial ectogenesis presently exists at both ends of the gestational period: (early) embryos can spend time in a petri-dish in the first few days of development; neonates can spend months in an incubator at the other. It may, and frequently is, glibly assumed that it is only a matter of time before improvements at both ends "meet in the middle"-so to speak. 71 But considering the difference between incubation and ectogestation suggests things are rather more complicated. First, until 2017, none of the existing developments were actually ectogestation. Whilst ectogestation now seems feasible in the latter half of pregnancy, it is worth noting that IVF still does not involve ectogestation. For, plausibly, IVF precedes pregnancy; Kingma 72 intimates that implantation-at least in the case of IVF-is when a blastula becomes a physiological part of the pregnant organism. If that indeed defines the start of a pregnancy, then the challenge of ectogestation as opposed to ectogenesis, still has to be met, at the beginning part of pregnancy. ectogestational efforts do not focus on an interface in which the placenta may form, but on replacing fetal parts. The two developments may well meet in the middle, but such a meeting would not be seamless; the meeting may still require a transfer of the fetal body from its previous womb-like artificial environment or vascular interface, onto ectogestative support technology that invasively removes and replaces its placenta and amnion. 73 We want to conclude with the following remark. In bioethics and philosophy there is a considerable metaphysical and ethical body of

CO N FLI C T O F I NTE R E S T
The authors declare no conflict of interest.