When is viability in a fetus




















Typically, the more intense the life-saving treatments, the greater the risk factors for these extremely small and fragile babies. However, it is difficult to tell precisely which babies will have problems and how severe these problems will be later in life. Some common long-term effects of being born very prematurely include:. If you expect to deliver an extremely premature baby, start a conversation with the doctors who will be caring for your baby about what type of resuscitation you would want for your child at which gestational ages.

This is undoubtably a difficult situation to face. However, considering these issues before they are happening can give you a chance to ask all the pertinent questions and think through these tough decisions before they need to be made. Among some questions parents who are facing a pre-term birth or who unexpectedly have one should ask:. There are so many variables to consider when delivering a preterm baby for both parents and medical professionals.

It is not merely a discussion of whether the baby survives the birth, but what the long-term outcomes for your baby are. If your baby was born prematurely or you expect your baby to be born prematurely, talk at length with your baby's doctor so you can be as prepared as possible and get the support you may need.

Parental support groups are invaluable to both yourself and others. Get diet and wellness tips delivered to your inbox. Outcomes for extremely premature infants. Anesth Analg. Very premature births: Dilemmas and management. Part 1. Outcome of infants born before 28 weeks of postmenstrual age, and definition of a gray zone. Arch Pediatr. American College of Obstetricians and Gynecologists. Periviable birth. Published June Between-hospital variation in treatment and outcomes in extremely preterm infants.

N Engl J Med. Centers for Disease Control and Prevention. Predictors of mortality and morbidity were similar in both cohorts. In other words, while survival of babies born between 22 and 25 weeks' gestation has increased since , 'the pattern of major neonatal morbidity and the proportion of survivors affected are unchanged'.

The authors further note that 'These observations reflect an important increase in the number of preterm survivors at risk of later health problems'. The study found 'improved survival to the end of the first week, with little difference thereafter':. Increased survival in the first week could result in a population entering the second week at higher risk of complications because of the survival of babies who would previously have died.

This is supported by increased reporting of sepsis confirmed by blood culture and necrotising enterocolitis as the primary cause of death in those surviving the first week. The EPICure studies have also closely monitored the progress of those babies that survive to the point where they are able to leave hospital, and grow into toddlers, then older children, then adults: the cohort will now be aged In , Johnson et al.

However, for the remaining 50 percent, the situation is much harder. The EPICure 2 study discussed levels of disability observed in children at the ages of two and three, and compared these findings to those from the cohort. Here again, there is some really good news. In , there were few differences between babies born at 23, 24 or 25 weeks; in , babies born at 24 and 25 weeks now have better outcomes than those born at the threshold of viability.

However, the contrast with babies born at weeks is stark: only a quarter of these extremely premature babies have no impairment at the age of three, and the same proportion has a severe impairment.

This indicates that, as with survival rates, improvements in the care of extremely preterm babies have had most impact for those at the upper end of the extreme prematurity spectrum; for those of threshold viability, the prognosis remains very uncertain. EPICure also points out that 'the proportion of babies who have the most serious problems is similar in in both studies and because the number of babies receiving care has risen that means that the number of children with problems related to their prematurity also has risen.

This is very important information as services need to be planned to be able to provide the support that the children and… their parents, need. Improvements in neonatal care do not reduce the resources required to care for those children who have disabilities as a result of their prematurity; arguably, as more extremely pre-term babies survive, the need for specialised health, care, and educational resources will become greater. Many countries, Britain included, impose legal 'time limits' on the gestation at which a fetus can be legally aborted.

In Britain, this limit is 24 weeks: unless a serious fetal anomaly has been detected, or unless there is a risk of 'grave permanent injury' to the physical or mental health of the pregnant woman, or to her life, in which case it is available up to term.

The argument that is often used to justify the week limit is that this is the point at which a fetus becomes 'viable'; therefore, it is treated by law more as a baby than a fetus. Ninety-nine per cent of all abortions in England and Wales take place at under 20 weeks' gestation. There are a number of problems with using ideas about viability as an argument against abortion.

First, as noted above, the situation of a woman going into premature labour with a wanted pregnancy, and that of a woman needing an abortion in the second trimester, are very different.

By the same token, the status of a baby spontaneously arriving too early, and the status of a pregnancy that a woman is still carrying, are very different: legally, morally, and emotionally. The reasons why women need late abortions, and the other arguments marshalled against late abortion, is discussed in a separate briefing.

With regard to often-made media claims that the improved survival of extremely pre-term infants raises questions about the legal time limit for abortion, we should be clear that this is a politically-motivated argument that exploits our very human desire that very premature babies survive and thrive to make us equate abortion with 'killing' born babies.

Yet as the Guardian's Polly Toynbee wrote on 1 September , 'The date at which a fetus might be viable has nothing to do with a woman's right to choose. Some day an embryo might be reared in a test tube to full term, but that changes nothing for a woman's right not to be a mother.

Accidental pregnancy or change in circumstance once pregnant crosses all classes. Abortion is very, very ordinary and a mark of civilisation — liberty for women and every child wanted. In the process, they would deny abortion to the most desperate cases who leave it the latest — the very young or the middle aged who thought they had gone through the menopause. The callous politicisation of improvements in the survival of extremely premature babies is damaging to women who need abortions in the second trimester of pregnancy.

It is also damaging to the discussion about how we, as a society, best care for very premature infants. By talking up the extent to which survival of very premature babies has improved, and glossing over the actual statistics and the problems that these babies are likely to face, parents of extremely premature babies can be provided with false hope.

Other factors that can affect the survival of very pre-term infants are often ignored. A girl is much more likely to survive than a boy, for instance, and the heavier the better. If we can give parents an individualised chance of survival, we really would be getting somewhere. John Wyatt is well known for his opposition to abortion — yet he recognises that collapsing together the issues of premature babies and abortion time limits profoundly distorts the terms of the discussions that we need to be having.

Meanwhile, those who wish to restrict women's access to abortion in the second trimester of pregnancy need to ask themselves one simple question. See your doctor or midwife if you have any pain when you pee. This could be sign of a urinary tract infection UTI that needs treating. Start4Life has more about you and your baby at 24 weeks.

You can sign up for Start4Life's weekly emails for expert advice, videos and tips on pregnancy, birth and beyond. Interestingly, there are inconsistencies between States regarding how long after being born a fetus would have to be physically able or likely to survive to be considered viable.

There are limited references to this in the legislation of most States adopting similar language to the English model , but there are some notable exceptions.

These definitions seemingly exclude those fetuses that might be delivered alive and survive only for a few seconds of independent life. Other States have only implicit definitions of viability. These States have statutes limiting abortion after a particular point in gestation.

There is much variance on the identified point of viability from 20 53 to 25 weeks. Despite the Supreme Court having affirmed a constitutional right to abortion until viability, by having left viability abstract without careful quantification, pregnant people have been rendered vulnerable. There is extreme inequity in access to reproductive healthcare including termination across the Country. It is bizarre that the Supreme Court would affirm a right but leave that right with absent parameters enabling States to construct their own criteria to accessing it.

There are several plausible reasons that might account for the significant discretion left to States on the content of this right. The viability threshold is broadly enunciated in law with significant scope for political interpretation.

It is important to note here that in there was a trend of State legislatures attempting to abandon the viability framework entirely.

These Acts have all, at the time of writing, been blocked by Federal Courts, 62 but they demonstrate a political determination among some legislatures to challenge Roe v. There is some legal recognition that there is a state interest in potential life in both the USA and England and Wales, which has resulted in some legislative protection for unborn fetuses.

There is incongruity, however, in ascertaining what viability means and the point at which viability occurs. First, exactly how a viability threshold has been established in law is different in each jurisdiction. While the term viability is used explicitly in the US legal framework established in Roe v. Wade , it does not feature in the criminal law in England and Wales at all.

Second, there are potential differences in these jurisdictions as to whether viability as a legal concept is considered distinct from medical conceptions of viability. The US Supreme Court has been clear that viability is a term intended to reflect medical possibility, and most States have legislated along these lines, though this approach is not adopted by all State legislatures.

In England and Wales, there remains debate as to whether viability is a strict legislative threshold or an ill-defined legal construction 63 that might therefore reflect medical opinion.

Third, there is a significant inconsistency in the GA of presumed viability. The US Supreme Court emphasizes that viability is a medical question, though judgments have posited fetuses which are viable from 23 weeks. There is also a significant variation in gestational limits at State level, including several US States with limits below 22 weeks.

It remains to be seen how the US Supreme Court would rule on the constitutionality of these fixed points if specifically challenged.

While there is inconsistency in terms of GA between and within jurisdictions, there is a common problem with all of these approaches; they all label fetuses as viable at a point in development when the data do not reflect a substantial likelihood of survival.

Even at 24 weeks, the likelihood of survival is dependent on access to the best medical care. Moreover, there is no evidence that a fetus could ever survive ex utero at some of the points that legislatures have identified less than 22 weeks even with intensive care, because the lungs would not yet be formed.

Survival with the aid of intensive care is dependent on a neonate having sufficiently formed lungs to tolerate artificial ventilation. In the following sections, I explore the coherency of viability in the law, by examining what kind of life ex utero the legal frameworks of England and Wales and the USA consider valuable.

This turns on whether viability is constructed as a rebuttable presumption or an evidential rule. In both jurisdictions, an isolated point in gestation is identified, formally or informally, as the point a fetus is assumed viable. Does this preclude fetuses younger than this point from being recognized as viable?

Does the law allow for the recognition that an individual fetus is not viable later in gestation? A consistent and coherent account of viability, that is carefully quantified, is not provided in English or US jurisprudence. The C v. S 69 judgment demonstrates the willingness of English judges to examine evidence regarding the viability of fetuses before the week threshold.

A newborn capable of only surviving with the aid of intensive care is considered viable in English law. There has been limited further clarification about what likely duration of life after birth is sufficient to establish that a fetus is viable. Viability is even less fixed in US law since the Supreme Court has refused to fix a point in gestation from which a fetus is presumed viable.

Individual States have thus been free to define viability and the point from which they will assume that fetuses are viable. Some states set a low threshold of presumed viability.

Anti-choice campaigns often attempt to validate arguments about reducing abortion time limits by referencing advances in medical technology and their impact on the viability timeline.

The likelihood of survival, and without serious complications resulting from care complications or developmental limitation, increases with GA. The Nuffield Council of Bioethics guidelines regarding resuscitation decisions specifies that resuscitation attempts on newborns below 22 weeks should not be attempted outside of recognized clinical trials.

Is some possibility of survival ex utero sufficient, or some possibility of a healthy life with longer-term survival prospects? Or even a reasonable likelihood of survival with good prospects for a healthy life?

There has been little change in the data regarding premature survival in recent years, as it appears that the clinical possibilities of conventional care to aid survival have been exhausted. There is, however, technology on the horizon thought capable of shifting the viability timeline earlier in gestation. Research scientists are explicit that they intend to mitigate the impact of being born premature rather than challenge current conceptions of viability.

They identify their clinical target population at 23—25 weeks, 85 as those who would already be subject to treatment in intensive care. I have argued elsewhere that in the initial stages of testing this technology, it should be used on those preterms that we would not consider viable, because to test it on preterms potentially able to survive in intensive care is to deny them medical treatment for potentially no benefit.

Moreover, if AAPT can better promote the survival of preterms on this current viability threshold, there will be calls to use the technology to aid those preterms delivered not far behind it. It is hard to speculate about how far AAPT may be able to stretch the viability timeline, as there will be other natural limitations. Future models may a long way in the future also be capable of sustaining even more primitive human entities.

While AAPT is a speculative development, the technology is an interesting example to examine the coherence of viability in the law. AAPT is conceptually distinct from other forms of preterm care because it is continuing the process of creating, rather than rescuing, developing human entities.

A fetus is a developing human entity undergoing the process of gestation dependent upon a pregnant person. A neonate, while developing still, is no longer undergoing a process of creation and must be capable of partially self-sustaining in the external environment. A gestateling is undergoing the process of gestation and is not ex utero in a meaningful sense, but it is not dependent upon a pregnant person. Insofar as any legal concept of viability has any utility, and it would distinguish between those fetuses that are capable of independent existence after gestation and those that are not.

Emergence from gestation involves the developing human entity undergoing meaningful biological adaptations enabling self-sufficiency, interaction with and survival in the ex utero environment even if they were dependent on rescue technologies in neonatal intensive care. Doctrinal lawyers are often criticized for considering the application of contemporary legal frameworks in different contexts—for example, the development of a future reproductive technology.

In such an exercise, therefore, we can consider how the law and the logics that underlie it need reform in line with technological developments. Thus, fetuses should only be considered viable when capable of maintaining some kind of supported independent existence following the biological state changes encompassed in birth.

English and US law thus have different approaches: English law is concerned with fetuses capable of being born and maintaining some independent life function, whereas in US law, the standard is stipulated in a way that sets the threshold lower; at just independence from a pregnant person. English law is concerned with the capacities of the developing human entity, whereas US law is not.

Some US States have passed legislation conceptually similar to the English approach—making specific reference to the capacities of the fetus—even though they are not required to set such specific standards. The reasons for the difference can be elucidated in the origins of the law in each jurisdiction. A human entity only has legal personality and can therefore be the victim of homicide, if it is born alive.

A human entity that is killed before being born alive cannot be recognized as a victim of homicide, but its death is recognized in the crime of child destruction. It is interesting that in both jurisdictions, there remains some extent to which the determination of viability even for the purposes of the law is a medical question.

It remains to be seen how the medical profession will respond to AAPT and whether the technology will be considered conceptually distinct from rescue technologies in practice and its impact on the viability timeline. For obvious reasons, there is yet little qualitative or quantitative data available about the attitudes of doctors toward viability and abortion provision in light of AAPT. In a study, 91 Australian doctors were asked closed questions about their conception of viability in the advent of such technology and its capacity to continue gestation of fetuses at 22 weeks.

If viability is a concept intended to meaningfully convey some notion of the potentiality of life, English law currently adopts the more coherent account of viability as applied earlier in gestation.

There is a meaningful developmental difference between a fetus no longer necessarily in need of being created because it could survive after gestation with conventional care and a fetus that cannot be sustained outside of gestation. The approach of the US Supreme Court is vague and encompassing of fetuses incapable of making the necessary biological state changes to demonstrate a completed birth. The legal framework of these jurisdictions considers viability a rebuttable presumption earlier in gestation, but what about those cases where the viability of a fetus later in gestation passed the point the law might presumes viability is questionable?

Examining to what extent the law is sensitive to the capacities of an individual fetus is an important aspect of ascertaining the substance of viability and what it intends to protect. If viability operates as a rebuttable presumption in one direction, to allow for recognition that a fetus earlier in gestation might be viable, it would be inconsistent not to recognize that some fetuses may not be viable later in gestation.

It is potentially possible to generalize that most fetuses will be sufficiently developed to survive with some assistance after a specific point in gestation; however, this will always depend on the particular circumstances. Anencephalic fetuses have a congenital absence of the brain, parts of the skull and scalp, and are inherently non-viable because the absence of a brain is lethal and irreversible in all cases.

In English law, there is provision for the termination of an anencephalic fetus even after 24 weeks the implicit viability threshold. There has been little clarification of the necessary severity of the handicap in these circumstances; however, it is clear that given the severity of anencephaly that abortion would be lawful here.



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