Fetal Reduction
Mark I. Evans, MD, and David W. Britt, PhD
Fetal Reduction has been employed over the past two decades as a mechanism to reduce
the morbidity and mortality of multiple pregnancies. Utilization of the procedure has
increased dramatically as IVF has become commonplace but the average starting number
has decreased with the transfer of fewer embryos. Success rates from fetal reduction have
improved as a function of increasing experience, better ultrasound, and lower starting
numbers. Genetic diagnosis prior to reduction can improve the overall outcomes. Reduction of triplets or more clearly improves outcomes, and reduction of twins to a singleton is
now a reasonable consideration.
Semin Perinatol 29:321-329 © 2005 Elsevier Inc. All rights reserved.
I
t will soon be 30 years since the birth of Louise Brown, the
first baby to come from in vitro fertilization (IVF). Since
that event, millions of babies have been born secondary to
infertility therapies, including more than 1,000,000 IVF babies. These incredible success stories, however, have had
corresponding serious side effects. The twin pregnancy rate,
commonly quoted for decades to be 1 in 90, has more than
doubled in the United States to more than 1 in 45. About
70% of all twins in the United States have come from infertility treatments. Some IVF programs create as many multiples as singletons.
All multiple pregnancies have continued to rise, and the
incidence of prematurity and related sequelae clearly correlate with fetal number (Fig. 1; Tables 1 and 2).1 With increasing public, professional, and legal attention, some of the very
high-order multiples have diminished, particularly secondary to lower transfer numbers of embryos in IVF. There are
some suggestions that the incidence of triplets and higher is
slowly diminishing, but the incidence is still very high.
In this arena, as with many others, it is often easier to
appreciate the numerator than the denominator. Published
pregnancy losses in multiple pregnancies are mostly a function of how early in pregnancy one establishes the actual
number of cases.2,3 Some reports by perinatologists are
overly, and we believe inappropriately, optimistic because
these physicians don’t start “counting” until they begin to see
patients in the second trimester, at which time most losses
have already occurred.3,4 Many other articles have addressed
those issues and will not be repeated here.4-6
Twenty years ago, about 75% of multifetal pregnancy pa-
tients seeking reduction had pregnancies initiated with ovulation induction agents such as Pergonal.7 However, even
with the first month of the lowest dose of Clomid, we have
seen quintuplets. Over the years, the proportion of multiples
induced by assisted reproductive technology (ART), such as
IVF, have increased steadily, and currently about 70% of the
patients we see seeking reduction have pregnancies generated by ART.8
Despite the increased utilization of ART, the proportion of
hyperstimulated cases that result in quintuplets or more has
dramatically decreased to less than 10% of all the cases we
see. Regardless, the 2002 report of the Society of Assisted
Reproductive Technologies (SART) published in December
2004 suggested that, of all pregnancies achieved following
ART in the United States, 50.9% are singletons, 37.8% twins,
6.9% triplets or higher, and 4.4% were unknown.8-10 By
birth, the percentages were 57.6% singletons, 39.6% twins,
and 2.8% triplets or higher, reflecting the increased pregnancy loss rate of higher order multiples.10 In our experience
with referred cases of ovulation stimulation, particularly
those using FSH analogues, the proportion of cases that are
quintuplets or more has fallen but not as dramatically.11
Such data continue to reinforce the significant role of vigilance in monitoring infertility therapies. It is our impression
that the vast majority of multifetal cases occur to physicians
with the best of equipment and the best of intentions who
have an unfortunate and reasonably unpredictable or unpreventable maloccurrence. Despite this, clearly some cases
might have been prevented if increased vigilance had been
used.11-13
Demographics
Fetal Medicine Foundation of America.
Address reprint requests to Mark I. Evans, MD, Comprehensive Genetics, 131 E.
65th St., New York, NY 10021. E-mail: EVANS@COMPREGEN.COM
0146-0005/05/$-see front matter © 2005 Elsevier Inc. All rights reserved.
doi:10.1053/j.semperi.2005.10.004
Over the past decade, the pattern of patients seeking multifetal pregnancy reduction (MFPR) has changed consider321
M.I. Evans and D.W. Britt
322
Figure 1 Risks of prematurity as a function of fetal number (2002 United States Centers for Disease Control Data).
Diagonal lines: preterm birth ⬍32 weeks. Shaded area: birth weight ⬍1500 g.
ably.11,12 With the rapid expansion of availability of donor
eggs, the number of “older women” seeking MFPR has increased dramatically. In our experience, over 10% of all patients we see seeking MFPR are over 40 years of age, and
nearly half of them are using donor eggs. As a consequence of
the shift to older patients, many of whom already had previous children, there is an increased desire by these patients to
have only one further child. The number of experienced centers willing to do 2 to 1 reductions is still very limited, but we
believe it can be justified in the appropriate circumstances.11,13
For patients who are “older,” particularly those using their
own eggs, genetic counseling and diagnosis becomes an important part of the process. By 2001, more than 50% of
patients in the United States having ART cycles were over 35
(Table 3).1,9,10,14 In the1980s and early 1990s, the most common approach was to offer amniocentesis at 16 to 17 weeks
on the remaining twins. However, a 1995 paper suggested an
Table 1 Multiple Births in the United States
Year
Twins
Triplets
Quadruplets
Quintuplets &
Higher Multiples
2002
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
1989
% Change from 1989-2002
125,134
121,246
118,916
114,307
110,670
104,137
100,750
96,736
97,064
96,445
95,372
94,779
93,865
90,118
38.9%
6898
6885
6742
6742
6,919
6,148
5,298
4,551
4,233
3,834
3,547
3,121
2,830
2,529
172.8%
434
501
506
512
627
510
560
365
315
277
310
203
185
229
89.6%
69
85
77
67
79
79
81
57
46
57
26
22
13
40
72.5%
Data taken from National Vital Statitics Report, Volume 52, #10, p22, 2003.
Fetal reduction
323
Table 2 Ratio of Observed to Expected Multiples
Births
Observed
Twins
Triplets
Quadruplets
Quintuplets & higher
multiples
125,134
6,898
434
69
Expected
44,686
496
6
0.07
Ratio
2.80:1
13.9:1
72.3:1
985.7:1
Total Births in 2002 - 4,021,726
11% loss rate in these cases, which caused considerable concern.15 Fortunately, the issue was settled by a much larger
collaborative series in 1998 that showed that loss rates were
no higher than comparable controls of MFPR patients who
did not have amniocentesis.16 The collaborative data show a
loss rate of 5%, which was certainly no higher than the group
of patients post MFPR who did not have genetic studies.
Since the centers with the most MFPR experience were also
the ones who had the same accomplishments with chorionic
villus sampling (CVS), combinations of the procedures were
very logical. There are two competing possibilities as to the
best approach to first trimester genetic diagnosis, ie, should it
be before or after the performance of MFPR? Published data
in the early 1990s suggested that performing the CVS first
followed by MFPR resulted in a 1% to 2% error rate as to
which fetus was which, particularly if the entire karyotype
was obtained.17 Therefore, for the first 10 to 15 years, the
approach we used was to generally do the reduction first at
approximately 10.5 weeks in patients reducing to twins or
triplets, followed by CVS approximately 1 week later.11,14
However, in patients going to a singleton pregnancy, essentially putting “all of their eggs in one basket,” we believed the
best approach was to know what was in the basket before
reducing the other embryos.11,12 In these cases we usually
performed CVS on all the fetuses or one more than the intended stopping number, and performed a fluorescent in situ
hybridization (FISH) analysis with probes for chromosomes
13, 18, 21, X, and Y. Whereas about 30% of overall anomalies
seen on karyotype would not be detectable by FISH with
these probes,18,19 the absolute risk of a remaining undetected
anomaly is very small. Given both a normal FISH and a normal ultrasound including nuchal translucency,20 the residual
risk is only about 1/400 to 1/500. We believe that such a risk
is lower than the increased risk from the 2-week wait necessary to get the full karyotype. We have now commonly extended this approach to all patients who are appropriate candidates for prenatal diagnosis regardless of the fetal number
(Fig. 2) Over the past few years, more than 75% our patients
have combined CVS and MFPR procedures. With data now
suggesting increased risks of chromosomal and other anomalies in patients conceiving by IVF and especially with intracytoplasmic sperm injection (ICSI), the utilization of prenatal
diagnosis will likely increase even further.21-26
Clinical Uses
MFPR is a clinical procedure developed in the 1980s where a
small number of clinicians in both the United States and
Europe attempted to reduce the usual and high adverse sequelae of multifetal pregnancies by selectively terminating or
reducing the number of fetuses to a more manageable number. The first European reports by Dumez27 and the first
American report by Evans and coworkers,28 followed by a
further report by Berkowitz and coworkers,29 and later Wapner and coworkers,30 described a surgical approach to improve the outcome in such cases.
Even these early reports appreciated the ethical dilemma
faced by couples and physicians under such difficult circumstances.13 In the mid 1980s, needles were inserted transabdominally and maneuvered into the thorax for the injection
of KCL or mechanical disruption of the fetus by either mechanical destruction, air embolization, or potassium chloride
injections despite relatively mediocre ultrasound visualization. Transcervical aspirations were also initially tried, but
with little success. Some centers also used transvaginal mechanical disruption, but data suggested a significantly higher
loss rate than with the transabdominal route.31 Today virtually all experienced operators perform the procedure by inserting needles transabdominally under ultrasound guidance, although some unpublished data have suggested that
some centers continue to use 6- to 8-week transvaginal reduction procedures despite considerably higher loss rates.
Results
Several centers with the world’s largest experience have collaborated to leverage their their data. In 1993 the first collaborative report showed a 16% pregnancy loss rate through 24
completed weeks.17 Such numbers represented a major improvement for higher order multiple pregnancies. Further
collaborative papers have shown continued dramatic improvements in the overall outcomes of such pregnancies (Table 4).11 The 2001 collaborative data demonstrated that the
outcome of triplets reduced to twins, and quadruplets reduced to twins, now perform essentially as if they started as
twins.11 Even with the tremendous advances in neonatal care
for premature babies, the 95% take home baby rate for those
who start with triplets and the 92% take home baby rate for
those who start with quadruplets clearly represent dramatic
improvements over natural statistics. Not only has the pregnancy loss rate been substantially lowered, but so has the rate
of very dangerous early prematurity. Both continue to be
correlated with the starting number. Data from the past few
years show that the improvements are, not surprisingly,
greatest from the higher starting numbers (Fig. 3).
The lowest pregnancy loss rates are for those cases reduced
Table 3 Maternal Age and ART (SART Data - 2001)
All Cases
Fresh Non Donor
<35
35-37
38-40
41-42
42ⴙ
81,915
60,780
28,778
14,416
11,301
4,365
2,190
M.I. Evans and D.W. Britt
324
Figure 2 CVS in multple pregnancies. CVS catheter inserted transcervically into posterior placenta. Anterior placenta
could be done easily by either the transcervical or transabdominal approach.
Table 4 Multifetal Pregnancy Reduction - Losses by Years
Losses
(weeks)
Deliveries
(weeks)
%
%
%
%
%
%
Total < 24 > 24 25-28 29-32 33-36 37ⴙ
1986-90 508
1991-94 724
1995-98 1356
From Evans et al.11
13.2
9.4
6.4
4.5
0.3
0.2
10.0
2.8
4.3
21.1
5.4
10.2
15.7
21.1
31.5
35.4
61.0
47.4
also suggested that adverse perinatal outcomes are more
common in IVF patients, specifically in singletons.33 There is
disagreement as to whether reduced triplets have better outcomes than those left alone. Yaron and coworkers34 compared triplets to reduced twins to those of unreduced triplets
with two large cohorts of twins. The data show substantial
improvement in patients reduced to twins as compared with
those with triplets. The data from the most recent collaborative series suggest that pregnancy outcomes for cases starting
at triplets or even quadruplets reduced to twins do as well as
starting as twins. Antsaklis and coworkers showed a reduc-
% Losses & Premature Delivery
to twins with increasing losses for those reduced to singletons
followed by reduction to triplets. However, the rate of early
premature delivery has been, not surprisingly, highest with
those left with triplets followed by twins and lowest with
singletons. Mean gestational age at delivery was also lower for
those left with more fetuses. Birth weights following MFPR
decreased, with starting and finishing numbers reflecting increasing prematurity.32
Although data in the literature are conflicting, our experience suggests that triplets reduced to twins do much better in
terms of loss and prematurity than do unreduced triplets. We
believe that, if a patient’s primary goal is to maximize the
chances of surviving children, that reduction of triplets to
twins achieves the best live born results. More recent analyses
suggest that, although mortality is lowest with twins, morbidity is lowest with remaining singletons. Recent data have
MULTIFETAL PREGNANCY REDUCTION
Losses and Very Prematures
by Starting Number
20
18
16 15.4
14
12
10
8
6
3.8
4
2
0
Starting # 6+
< 24 wks
25-28 wks
11.4
9.6
7.3
6.2
4.9
4.5
3.5
5
4
3
0.0
2
Figure 3 Multifetal pregnancy reduction losses and very prematures
by starting number. (Modified from Evans et al.11)
Fetal reduction
325
Table 5 Reduced vs “Unreduced” Triplets Comparison
MFPR Cases
Deliveries (weeks)
Years
Losses <24 wks
1980s
90-94
95-98
98-02
6.7%
5.7%
4.5%
5.1%
98-02(3ⴚ>1)
8.0%
24-28 wk
29-32
33-36
6.1%
5.2%
3.2%
4.6%
Mean GA 35.5
4.0%
Mean GA 39.5
9.1%
9.9%
6.9%
10.8%
36.9%
39.2%
28.3%
41.8%
PMR 10.0/1000)
4.0%
PMR 0/1000
12.0%
37ⴙ
47.9%
45.2%
55.1%
37.6%
72.0%
Non Reduced Triplets
98
99
99
02
(Leondires)
(Angel)
(Lipitz)
(Francois)
9.9%
8.0%
25.0%
8.3%
Mean
Mean
Mean
Mean
GA
GA
GA
GA
33.3
32.3
33.5
31.0
PMR
PMR
PMR
PMR
55/1000
29/1000
109/1000
57.6/1000
From Evans MI, Krivchenia EL, Kaufman M, et al: The optimal management of first trimester triplets. The Central Association of Obstetricians
and Gynecologists. Annual Meeting, Las Vegas, Nevada, October 27-30, 2002.
tion of losses from 15.41% to 4.76% for twins and diminishment of low birth weight fom 28% to 11%.35 These data
therefore support some cautious aggressiveness in infertility
treatments to achieve pregnancy in difficult clinical situations. However, when higher numbers occur, good outcomes
clearly diminish. Luke and coworkers have suggested that, in
twin pregnancies with assisted reproduction, fetal reduction
increased the risks for birth at ⬍30 weeks, very low birth
weight, and slowed midgestational growth.36 This analysis,
however, ignores the starting conditions, ie, how did they do
compared with keeping triplets or quadruplets? Kozinsky
and coworkers showed that the perinatal outcomes of singleton and twin pregnancies following ART were comparable to
spontaneously conceived, matched pregnancies.37 McDonald and coworkers have recently shown in a metaanalysis
that twins from IVF, even when matched to spontaneously
conceived twins, had a somewhat higher risk for preterm
birth but no significant differences in perinatal deaths, congenital malformations, or low birth weight.38 A 2001 paper
suggested that reduced triplets did worse than continuing
ones.39 However, analysis of that series showed a loss rate
following MFPR twice that seen in our collaborative series11
and poorer outcomes in every other category for remaining
triplets Several other recent papers have likewise shown
higher risks for “unreduced” triplets than for reduced
cases.40-43 It is clear that one must use extreme caution in
choosing comparison groups (Table 5). Blickstein has reported that triplets do worse than reduced twins in every
perinatal category in his large database.44
An ever increasing situation involves the inclusion of a
monozygotic pair of twins in a higher order multiple.45 Our
experience suggests that, provided the “singleton” seems
healthy, the best outcomes are achieved by reduction of the
monochorionic twins. Obviously, if the singleton is not
healthy, then keeping the twins is the next choice.
Pregnancy loss is not the only deleterious outcome. Very
early preterm delivery correlates with the starting number.
However, it has not been well appreciated that about 20% of
babies born at less than 750 g develop cerebral palsy.46 In
Western Australia, Peterson and coworkers showed that the
rate of cerebral palsy was 4.6 times higher for twins than
singletons per live births, but 8.3 times higher when calculated per pregnancy.47 Pharoah and Cooke calculated cerebral palsy rates per 1000 first year survivor at 2.3 for singletons, 12.6 for twins, and 44.8 for triplets.48 In a small series in
a report of a questionnaire, Dimitiriou and coworkers
showed no differences between triplets and twins, but there
is not enough power to reach such conclusions.49
In the 2001 collaborative report, the subset of patients who
reduced from two to one (not for fetal anomalies), included
154 patients. These data suggested a loss rate comparable to
three to two, but, in about one-third of the two to one cases,
there was a medical indication for the procedure, eg, maternal cardiac disease, prior twin pregnancy with severe prematurity, or uterine abnormality.11 In recent years, however, the
demographics are changing, and the vast majority of such
cases are from women in their 40s, or even 50s, some who of
whom are using donor eggs and who, more for social than
medical reasons, only want a singleton pregnancy.50-52 New
data suggest that twins reduced to a singleton do better than
remaining as twins.13 Consistent with the above, more
women are desiring to reduce to a singleton. In a recent series
of triplets, we found the average age of outpatients reducing
to twins to be 37 years and to a singleton, 41 years.50 Although the reduction in pregnancy loss risk for three to one is
not as much as three to two (15% to 7% and 15% to 5%,
respectively), the gestational age at delivery for the resulting
singleton is higher, and the incidence of births ⬍1500 g is 10
times higher for twins than singletons.1 These data have
made counseling of such patients far more complex than
previously (Figs. 4 and 5). Not surprisingly, there are often
differences between members of the couple as to the desirability of twins or singleton.52 There are also profound public
health implications to these decisions, as 2000 United States
326
Figure 4 Risk reduction as a function of starting number. Numbers
on left are risks of spontaneous loss without reduction. Numbers on
right are after reduction.
Data show that, of $10.2 billion spent per year on initial
newborn care, 57% of the money is spent on the 9% of babies
born at ⬍37 weeks.53 In 2003, more than $10 billion was
spent on the 12.3% born preterm.54 Data are now also emerging that there are considerably higher neurologic and developmental disabilities in 6-year-olds who survive after being
born at 26 weeks or less. The rates of severe, moderate, and
mild disabilty were 22%, 24%, and 34%, respectively. Significant cerebral palsy was present in 12%.55 Hack et al. have
now shown that, in babies born at less than 1000 g, the rate
of cerebral palsy was 14% as opposed to 0% for controls.
Asthma, poor vision, IQ ⬍85, and poor motor skills were all
also substantially higher.56 As a result of the changing demographics of infertility and MFPR, we believe that reduction of
twins to a singleton is likely to become more common over
the next several years.
M.I. Evans and D.W. Britt
believe this is a frivolous procedure, but see it in terms of the
principle of proportionality, ie, therapy to achieve the most
good for the least harm.13,57-59 In this section, we review a few
studies that have immediate implications for MFPR clinics
and ART clinics by virtue of giving some insight into how
patients frame the decisions they are making and structure
their social environments so as to reduce the risk of hostility
in reaction to these choices.
How patients “hear” and internalize data and make decisions with respect to reduction have been fascinating to us
over the years. Much of the literature on medical decision
making has emphasized a rational choice model that puts
hard data regarding relative risks center stage and treats emotions, feelings, and values as complications that should be
considered only as a second-stage analysis.60,61 Even in the
literature that talks about genuine alternative models of decision making (systematic versus heuristic, for example), a
central assumption is that there are individual differences in
style that can be identified through what people say.62,63
We have approached this problem from a different direction, arguing that where controversial, high-anxiety decisions are concerned, patients treat these decisions as an ongoing part of the social reality that they are creating to live in
and raise a family.64 This reality-construction process is proactive, with couples aware of the potential consequences of
sharing with others what they are going through. In a recent
study of sharing strategies among MFPR patients, we discovered four sharing strategies that varied in how selectively
their situation and choices were shared.65 Strategies for sharing ranged in terms of selectivity from a defended-relationship
approach, in which only the partner and patient knew about
the problems the patient was facing, and the decision to
reduce through a qualified family and friends strategy, in which
information is shared only with those who appear to be trustworthy in terms of their reactions. Two less selective strategies also emerged from our analysis. In the first, both sets of
Societal Issues
MFPR will always be controversial. We believe that the real
debate over the next 5 to 10 years will not be whether or not
MFPR should be performed with triplets or more. A serious
debate will emerge over whether or not it will be appropriate
to offer MFPR routinely for twins, even natural ones for
whom the outcome has been considered “good enough.”50
Our data suggest that reduction of twins to a singleton actually improves the outcome of the remaining fetus.50 No consensus on appropriateness of routine two to one MFPR, however, is ever likely to emerge. We do, however, expect the
proportion of patients reducing to a singleton to steadily
increase over the next several years.
Over the years, much has been written on the subject.
Opinions on MFPR, in our experience, have never followed
the classic “pro-choice/pro-life” dichotomy.2,7,11,14 Opinions
will always vary substantially from outraged condemnation
to complete acceptance. No short paragraph could do justice
to the subject other than to state that most proponents do not
Figure 5 Risks starting with triplets. Reduction of triplets to twins
has lower loss rates but higher incidence of prematurity, low birth
weight, and infant mortality than reducing to a singleton. Numbers
on left are risks with triplets, in the middle risks with twins, and on
the right, risks with a remaining singleton. (Color version of figure is
available online.)
Fetal reduction
327
Table 6 Frame Comparison
Medical Frame
Intensity of Commitment to having
children
Intensity of training in medicine,
dentistry, hard sciences and the
law
Intensity of commitment to belief
that life begins at conception
Intensity of commitment to career
Source of moral authority for
resolution
Fundamentalist Frame
Lifestyle Frame
High
High
High
High
Low
Modest
Modest
High
Modest
High
Relative survivability of
fetuses
Low
Minimization of damage to moral
beliefs though a “barely
sufficient” reduction
High
Having a “normal” life in
a culture that values
both careers and
family for women
parents are privy to what the couple is going through, and
finally, there is an extended, open network strategy of family,
friends, and colleagues being in the loop.
No sharing strategy is completely free of the risk of encountering hostility. Even so, the odds of encountering hostility are significantly greater with the more open, less selective strategies. MFPR and ART clinics will vary in terms of the
cultural style they have for handling patient anxiety and
stress, but these results suggest that some way should be
found to sensitize couples to the fact that selectively sharing
what they are going through is an effective technique for at
least neutralizing some of the hostility that they are at risk of
confronting from family, friends, and others. To the extent
that anxiety and stress have implications for clinic success
rates, such results regarding sharing strategies become doubly important.
The realities people construct— composed of supportive
people and institutions together with complexes of supportive values, norms, and attitudes—are what patients use to
view the data.57-59 The decisions they make and how they
justify those decisions may help resolve incompatible elements in the realities in which they find themselves enmeshed. It may often happen, for example, that parents who
have gone through reduction to two or one live in families
and/or work in communities where having engaged in reduction would be considered as something shameful. The less
control they have over the selection of family, friends, and
workplaces, given the prospect of such stigma, the more
likely they are to simply present their pregnancies to these
publics as if their pregnancies had always involved twins or a
singleton. Where they have more control over the situation—as typically happens with friends versus family—they
may be more likely to selectively share their experiences.
The social realities in which people live, however, involve
more than people: they also involve values, norms, and attitudes. The one thing all MFPR patients have in common is a
very strong desire to have a family (Table 6). But there does
not appear to be a single set of supportive institutions, people, and norms that is conducive to going through the pain,
stress, and resource expenditure of IVF. Rather, there are
three alternative resolutions. The first of these, a rational
Medical Frame, looks superficially like what one would ex-
pect from the rational analysis model. But the commitment to
factual analysis comes from patients’ having selected themselves into the hard sciences, medicine, dentistry, engineering, or the law— disciplines in which an appreciation of and
trust in “facts” form a fundamental part of their disciplinary
identity. Such women will want to see the numbers regarding
the relative risk associated with different reduction choices
and will want to engage in a rigorous discussion of the data
and their implications. And they will be likely to choose a
final number for reduction that maximizes the chances of a
“take-home” baby.
The lens of scientific objectivity is not the only frame
through which women who have gone through IVF to have a
child will examine these data (Table 6). For those who have
immersed themselves in a social reality that has a strong
emphasis on norms against abortion and/or reduction—such
that they themselves have such normative beliefs and are
heavily involved in religious institutions which reinforce similar beliefs—a detached examination of the “facts” is simply
not possible. These “facts” hold no special moral authority
and need not be trusted in and of themselves. Their beliefs
and those of the individuals and social institutions in which
they have selected themselves have a moral authority as well.
The balance that such women will likely seek is one that
reduces their relative risk to acceptable limits. So, unless the
consequences are dire, they will not reduce at all or choose to
reduce only to three. We labeled such a resolution a Conceptionalist Frame.
Finally, there are those for whom the demands of career
and/or existing children constitute powerful elements in their
constructed realities. For such women—and this includes
many of the older patients we encountered—the essential
balance that they seek is a more secular one, a Lifestyle
Frame, one that emphasizes creating a family situation in
which having a family can be balanced with working, though
the commitment to working is less than the intense career
commitment seen among Medical Frame patients. Such
women will more than likely choose reduction to two or even
one depending on the number of other children they have
and the level of resources that the family has.
Clinicians and their counseling staff need to be aware that,
to women who have selected themselves into and/or been
328
trained to accept the legitimacy of rigorously determined statistics regarding relative risk (a Medical Frame), reduction
choices can be straightforward; or at least they can appear to
be relatively straightforward. This is usually not the case,
however, for women who must forge a resolution among
potentially incompatible elements, as for women who are
struggling to reconcile the potentially oppositional elements
of religious beliefs and involvement with risks associated
with higher-level pregnancies (Conceptionalist Frame), or
those who are struggling to reconcile the potentially conflicting identities of home and work (Lifestyle Frame).
Clinics have different styles of dealing with the multisourced anxieties with which patients walk through the door.
The results that we have presented suggest that there is no
“one size fits all” way of counseling and supporting patients.
We expect, however, that successful clinics will have developed ways of understanding better where patients are coming from and what types of information and support will help
them the most.
Summary
Over the last two decades, MFPR has become a well-established and integral part of infertility therapy and the attempts
to deal with sequelae of aggressive infertility management. In
the mid 1980s, the risks and benefits of the procedure could
only be estimated.10-14 We now have very clear and precise
data on the risks and benefits as well as an understanding that
the risks increase substantially with the starting and finishing
number of fetuses in multifetal pregnancies. The collaborative loss rate numbers, ie, 4.5% for triplets, 8% for quadruplets, 11% for quintuplets, and 15% for sextuplets or more,
seem reasonable ones to present to patients when the the
procedure is performed by an experienced operator. Our
own experience and anecdotal reports from other groups
suggest that less experienced operators have worse outcomes.
Pregnancy loss is not the only poor outcome. The other
main issue with which to be concerned is very early preterm
delivery and the profound consequences to such infants.
Here again, there is an increasing rate of poor outcomes correlated with the starting number. The finishing numbers are
also critical, with twins having the best viable pregnancy
outcomes for cases starting with three or more. However, an
emerging appreciation that singletons have prematurity rates
less than twins is making the counseling far more complex.
We continue to hope, however, that MFPR will become obsolete as better control of ovulation agents and assisted reproductive technologies make multifetal pregnancies uncommon.
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