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Ethical considerations in embryo-reduction
Aris T. Papageorghiou
St. George’s University of London, Cranmer Terrace, London SW17 0RE, UK
The incidence of multifetal pregnancy has increased dramatically with the introduction of
artiﬁcial reproductive techniques (ART). These pregnancies are at high risk for maternal,
perinatal and long-term complications, and embryo reduction (ER) has been used for a
number of years in an attempt to improve these outcomes. In high-order multifetal
pregnancies ER is associated with a decrease in the background risk of miscarriage and
perinatal death, but there are some questions regarding the beneﬁts of reduction in triplet
pregnancies. The importance of preventative ethics, by restricting the number of embryos
transferred or careful monitoring of ovulation induction agents is generally agreed upon.
Regulation of treatment regimes coupled with reﬁnements to ART, have reduced the rate
of triplet- and higher-order multifetal pregnancies in the last few years. In this article, the
moral status of a fetus is discussed and biomedical ethical principles are examined in the
context of ER. In addition, religious considerations and medical guidelines are discussed.
&2006 Elsevier Ltd. All rights reserved.
Over the last 25 years the incidence of multifetal pregnan-
cies has increased dramatically. For example, although the
incidence of twin births is commonly quoted as about 1 in
90, in the USA it has trebled to almost 1 in 30. For triplet-
and higher-order multiples the increase has been even more
pronounced: in the USA, the rate of triplet- and higher-order
multiple birth rates between 1980 and 1998, surged from 37
to 193 per 100,000 live births, an increase of more than
500%; while in the UK the rates increased from 15 to 48 per
100,000, respectively. Although many factors, including
maternal age, parity and racial background inﬂuence the
incidence of multifetal pregnancy, it is the use of assisted
reproductive techniques (ART) that are thought to have
caused the majority of this increase. The risk of multifetal
pregnancy from ART correlates with the number of embryos
Multifetal pregnancies are at higher risk for maternal,
perinatal and long-term complications when compared with
singletons or twins. Embryo reduction (ER) has been
advocated for a number of years in order to improve these
outcomes. The procedure is most commonly carried out
transabdominally, by ultrasound-guided fetal intracardiac
injection of potassium chloride, but the transvaginal route
has also been used to aspirate the gestational sac using
suction. The disadvantage of the latter is that it is
performed earlier in pregnancy (around 7–8 weeks) there-
fore precluding an 11–13 week scan for examination for
fetal defects and measurement of fetal nuchal translucency;
in addition, the possibility of spontaneous loss of a
pregnancy is higher in early pregnancy.
There is good evidence that in high-order multifetal
pregnancies (i.e. quadruples and more) ER is associated with
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Current Obstetrics & Gynaecology (2006) 16, 181–184
a decrease in the background risk of miscarriage and
perinatal death. However, there are some questions
regarding the beneﬁts of reduction in triplet pregnancies.
Data suggest improvements in outcomes after ER with time
and increased operator experience; but there are concerns
regarding longer-term safety of ER. For example, observa-
tional data suggesting that death of a co-twin increases the
risk of cerebral palsy for the surviving twin by a factor of
eight when compared with the risk for twins when both
survive. Finally, there have also been improvements with
time in neonatal care and improved mortality statistics in
prematurity-related complications, meaning that for triplet
pregnancies there is some controversy concerning the
possible beneﬁts of reduction. A recent Cochrane review
found no randomised, controlled trials comparing outcomes
after ER with expectant management, and concluded that
results and conclusions from non-randomised studies are
limited by potential bias and must be interpreted with
The aim of this article is to give some insights into the
ethical problems surrounding ER in multifetal pregnancy.
Couples faced with multifetal pregnancies have three
options of management: termination of the entire preg-
nancy; continuing with the entire pregnancy; or ER by
selective termination. The issues surrounding ER and the
complications arising from multifetal pregnancy create a
bitter irony for infertility patients; these difﬁcult choices
affect mainly couples who have undergone long-standing
efforts to achieve pregnancies by ART. From the ethical
viewpoint, what parents chose will depend on their social
and religious background, but also on the medical evidence
that is presented to them. The difference between
termination of the whole pregnancy and ER is that in the
latter the intention is not to terminate the pregnancy but to
increase the chance of normal development of the remain-
ing fetuses, making the ﬁrst priority the well-being of the
children that will be born. Although there is little doubt that
this is true for high-order multiples, in the case of triplet
pregnancy there is some debate regarding the medical
beneﬁts of ER. So what ethical considerations are there
other than medical evidence?
Most authors start their discussion of ethical considerations
by emphasising the importance of preventative ethics. So, in
the case of ART, the incidence of multifetal pregnancy can
be reduced by restricting the number of embryos trans-
ferred, or by careful monitoring of ovulation induction
agents and avoidance of fertilisation. Such restrictions need
to follow careful discussion during the informed consent
process, including ethical reasoning and decision-making, as
well as consideration to the woman’s wishes regarding the
possibility of ER, in order to avoid conﬂicts between the
woman and her physician. Importantly, over the last few
years there has been both voluntary and statutory regulation
of treatment regimes. It is thought that implementation of
such regulations, coupled with reﬁnements to ART, have
been responsible for the reduction in the rate of triplet- and
higher-order multifetal pregnancies that has been observed
The moral foundation of modern biomedical ethics is based
upon four prima facie principles: respect of autonomy,
beneﬁcence, non-maleﬁcence, and justice. These can be
summarised as follows:
Autonomy: The patient has free will and accord, has the
right to information and self-determination. The patient
can chose to intentionally participate or decline treat-
Beneﬁcence: The patient’s welfare is the ﬁrst considera-
tion, so do what clinically beneﬁts the patient.
Non-maleﬁcence: First do no harm—but remember there
can be a balance between risk and beneﬁt.
Justice: Do not discriminate (for example on the basis of
age, sex, and race), be consistent, accountable and
respect the law.
These principles obviously apply to the pregnant mother,
but do all of them also apply to the fetus? And in the case of
multifetal pregnancy, do they apply to each fetus, or to the
pregnancy as a whole? In order to answer this question we
must ﬁrst consider the moral status of the fetus.
Moral status of a fetus
Persons have rights, for example the right to life, to thrive
and to be protected from harm. In considering the issue of
termination of pregnancy, Hope and colleagues discuss the
number of possible views on the moral status of the fetus:
(i) Identity as a human organism: According to this view
there are no good grounds for according a different
moral status to the human being at different stages in
its development. Most supporters of this position put
the moment at when the embryo attains full moral
status as conception. Before conception neither the egg
nor the sperm can be said to have the same identity as
the later child, but once conception has taken place the
organism that will be the child has come into existence.
(ii) The potential to be a person: This differs from the
argument of human identity (above) in that it does not
accord fetuses and embryos moral status for what they
are but because of what they have the potential to
become. According to the argument from human
identity, killing the fetus is wrong because you are
killing something that has the right to live. According to
the argument from potential, killing the fetus is wrong
because it involves carrying out an act that will have
the effect of preventing a future person from existing.
(iii) Identity as a person: This view is that a person is a
human being that has certain characteristics. An
embryo or fetus (or baby) is a moral entity only at the
point when it becomes a person. Most proponents of
this approach hold that being a person must involve
some degree of consciousness, and on most forms of this
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view, fetuses less than 24 weeks do not have moral
(iv) Conferred moral status: This states that moral status
need not be based only on intrinsic properties of the
entity (position 3 above), but that it can be conferred
by others. Thus, conferring moral status at birth can be
justiﬁed in terms of the consequences for others and in
terms of fostering concern, warmth and sympathy for
The authors go on to suggest that each of the four views
faces problems: while the ﬁrst two positions appear to give
too much moral protection to very early embryos, the third
position may give too little protection to infants and people
with severe learning difﬁculties. The fourth position seems
to many to exaggerate the importance of others at the
expense of the individual.
McCullough and Chervernak argue that there are irrecon-
cilable differences among philosophic and theological
methods that have been deployed over the centuries of
debate about the independent moral status of the fetus.
Their suggested line of argument is that the moral status of
the fetus depends on whether it is reliably expected later to
achieve the moral status of becoming a child and later that
of being a person. There are two possible links between a
fetus and child (and then person). In the case of a
potentially viable fetus this is being presented to a physician
and involves medical interventions that can result in ex-
utero life. The viable fetus, when the pregnant woman
presents herself for medical care, is therefore a patient.
However, it is important to stress that obligations to the
fetus must be considered along with beneﬁcence-based and
autonomy-based obligations to the pregnant woman. In the
case of the pre-viable fetus, technological factors cannot
result in the fetus becoming a child. The link is therefore
being presented to a physician and the decision of the
pregnant woman to continue a pre-viable pregnancy to
viability and, subsequently, to term. Thus, the pre-viable
fetus is a patient solely as a function of the pregnant
woman’s decision to confer the status on the fetus and
present herself for care, and the fetus has no claim to the
status of being a patient independently of the pregnant
woman’s autonomy: the pregnant woman can withhold,
confer and withdraw previously conferred moral status of
being a patient according to her own values and beliefs.
Ethics in ER
Using this background Chervernak and McCullough go on to
suggest that in high-order multifetal pregnancy, were the
pregnant mother to confer the same status on all fetuses
this would jeopardise the whole pregnancy. In fact, for some
of the fetuses to become patients she withholds conferring
this status on others, thus justifying fetal reduction.
Another argument that is commonly put forward is that
the medical justiﬁcation for the procedure is philosophically
similar to the ‘lifeboat analogy’—some drowning people can
legitimately be denied access to a dangerously full lifeboat
if bringing them aboard would cause it to sink and result in
the loss of additional lives. In the case of multifetal
pregnancy, this translates into the argument that it is
justiﬁable to sacriﬁce some normal fetuses in order to
increase the chances of survival, or decrease the risk
morbidity, in the remaining fetuses.
Religious considerations differ. In the catholic faith the
embryo is considered and treated as a human person from
the ﬁrst moment of conception, having fundamental human
rights, including (and foremost) that of the right to life.
From this viewpoint,
‘‘ythe moral prohibition remains even in the case where
the continuation of the pregnancy involves a risk to the
life or to the health of the mother and of the other
Conversely in Judaism, fetuses have no independent
moral status, and most Rabbinic decisors agree that ER is
permitted in certain circumstances. Some permit this only in
situations where the continuation of the pregnancy threa-
tens the mother’s life; others allow it in multifetal
pregnancy as in this case the pregnancy itself is threatened.
Muslim law is relatively lenient with regard to the abortion
of disadvantaged fetuses. In the case of ER it is permitted
only if the prospect of carrying the pregnancy to viability is
very small, or if the mother’s health or life is threatened.
The European Society of Human Reproduction and Embryol-
ogy (ESHRE) Task Force on Ethics and Law Ethical published
guidance on issues related to multifetal pregnancies.
Regarding ER, they comment that ethical dilemmas are
closely connected to the problem of abortion, but with the
main difference being that that the intention not to
terminate the pregnancy but to increase the chance of
development of the remaining fetuses. They go on to
comment that, especially in higher-order pregnancies, not
performing a reduction will increase the risk of losing the
pregnancy and all the fetuses, and that in a sense the
reduction is medically indicated. Prevention of multifetal
pregnancies should be preferred because the decision to
reduce the number of embryos is psychologically and
morally demanding, as well as carrying detrimental effects
(higher incidence of prematurity) on the development of the
remaining fetuses. They conclude that reduction
‘‘yis morally acceptable if the physician has acted
according to the rules of good clinical practice and has
tried to minimise the risk of a multifetal pregnancy. The
beneﬁts for the remaining embryos of reducing a higher-
order multifetal pregnancy exceed the disadvantages of
carrying the pregnancy to term or risking miscarriage.
With triplets, opinions vary according to personal
experience and access to neonatal care. The reduction
of twins to a singleton is acceptable in cases of maternal
disease, poor obstetric outcome and compelling social
and psychological reasons of the woman.’’
The Committee on Ethics of the American College of
Obstetrics and Gynecology also points out that there is a
distinction between ER reduction and selective termination
of an abnormal fetus and that therefore its ethical rationale
is different; that the ﬁrst approach should be prevention;
and that there is a need for careful counselling beginning
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Ethical considerations in embryo-reduction 183
before treatment for subfertility starts and continuing
throughout a patient’s care. They conclude that
‘‘yno physicians need participate in any activities that
they ﬁnd morally unacceptable, [but that] all physicians
should be aware of the medical and ethical issues in these
complex situations and be prepared to respond in a
professional, ethical manner to patient requests for
information and procedures.’’
These points are also highlighted by the French National
Consultative Ethics Committee for Health and Life Sciences.
In addition they advise that ‘Physicians using such techni-
ques must be adequately trained y’ and that ‘The
possibility of resorting to embryo or foetal reduction cannot
excuse or justify lack of caution in the use of these
The constant and dramatic rise in the incidence of multifetal
pregnancy has been slowed over the last few years, and this
is likely to be due to regulations as well as reﬁnements to
ART. From a preventative ethics point of view, this is a
positive outcome as choosing ER is psychologically and
morally demanding and carries detrimental effects. High-
order multifetal pregnancy carries such high risks to the
mother and the pregnancy itself that ER can be ethically
justiﬁed on the consideration of beneﬁcence (a balance of
greater clinical good over clinical harm). It can be argued
that the fetus can be considered not to have an independent
moral status, unless such a status is conferred upon it by the
mother. In view of this, ER can also be justiﬁed on the
principle of respect for the autonomy of the pregnant
mother (a balance of greater good over harm as deﬁned by
the patient’s perspective). This justiﬁes ER in cases where
the issue of beneﬁcence is not as clearly documented, such
as in triplet pregnancy.
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