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Ethical considerations of early (first vs. second trimester) risk assessment disclosure for trisomy 21 and patient choice in screening versus diagnostic testing

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American Journal of Medical Genetics Part C (Seminars in Medical Genetics) 145C:99 – 104 (2007)
A R T I C L E
Ethical Considerations of Early (First vs. Second
Trimester) Risk Assessment Disclosure for
Trisomy 21 and Patient Choice in Screening
Versus Diagnostic Testing
GEETA SHARMA,* LAURENCE B. MCCULLOUGH, AND FRANK A. CHERVENAK
We discuss the clinical implications regarding disclosure of risk assessment for trisomy 21 screening results in the
first versus second trimester. Based on the ethical principles of respect for autonomy, beneficence, and justice, we
argue that routinely offering first trimester risk assessment in centers qualified to provide it is ethically obligatory
and routinely withholding the results of first trimester risk assessment is ethically unjustified. As risk for trisomy
21 occurs along a continuum, no pregnant woman is without risk; thus, offering diagnostic testing to all women is
ethically justified. Informed consent and personal choice regarding diagnostic testing and termination of
pregnancy shape patients’ decisions to undergo first trimester risk assessment for trisomy 21. Appropriate
counseling is required to allow for individual choice regarding timing of disclosure. ß 2007 Wiley-Liss, Inc.
KEY WORDS: ethics; screening; risk assessment
How to cite this article: Sharma G, McCullough LB, Chervenak FA. 2007. Ethical considerations of early
(first vs. second trimester) risk assessment disclosure for trisomy 21 and patient choice in
screening versus diagnostic testing. Am J Med Genet Part C Semin Med Genet 145C:99–104.
INTRODUCTION
Ethical principles provide action guides
for physician’s clinical judgment, deci-
sion making, and behavior in patient
care. The basic ethical principles of
respect for autonomy, beneficence, and
justice and are integral to patients’
Geeta Sharma, M.D., is an Assistant Professor of Obstetrics and Gynecology in the Department
of Obstetrics and Gynecology, Division of Maternal Fetal Medicine at the New York Presbyterian
Hospital, Weill Medical College of Cornell University.
Laurence B. McCullough, Ph.D., is a philosopher who serves as Professor of Medicine and
Medical Ethics, in the Center for Medical Ethics and Health Policy, Baylor College of Medicine,
Houston, Texas. His research interests focus on ethics in obstetrics and gynecology, surgical
ethics, and the history of medical ethics.
Frank A. Chervenak, M.D., currently serves as the Given Foundation Professor and Chairman of
the Department of Obstetrics and Gynecology, as well as Obstetrician and Gynecologist-in-Chief
and the Director of Maternal Fetal Medicine at the New York Presbyterian Hospital, Weill Medical
College of Cornell University. He has published over 200 papers in peer review literature and has
co-authored or co-edited 18 textbooks. Research interests include ultrasound and ethics in
obstetrics and gynecology and leadership.
Dr. Chervenak has served on the Board of Governors of the American Institute in Ultrasound
and Medicine and the Society of Perinatal Obstetricians. He has served as President of the
International Fetal Medicine in Surgery Society, the New York Perinatal Society and the New York
Academy of Medicine Section of Obstetrics and Gynecology, and the New York Obstetrical
Society. Currently, Dr. Chervenak serves as President of the International Society of the Fetus as a
Patient, President-elect of the World Association of Perinatal Medicine, Vice-president of the
International Academy of Perinatal Medicine, and Co-director of The Ian Donald Inter-University
School of Medicine and Ultrasound. He serves on the March of Dimes Bioethics Advisory
Committee and National Children’s Study Federal Advisory Committee. He is an honorary
member of the Italian Society of Obstetrics and Gynecology, Barcelona Society of Obstetrics and
Gynecology and the Texas Society of Obstetrics and Gynecology, and a Corresponding Member
of the Academy of Medical Science of Croatia.
*Correspondence to: Geeta Sharma, M.D., Department of Obstetrics and Gynecology, Weill
Medical College of Cornell University, 525 East 68th Street, J-130, New York, NY 10021.
E-mail: gsharma@med.cornell.edu
DOI 10.1002/ajmg.c.30118
ß 2007 Wiley-Liss, Inc.
choices regarding individual risk assessment for trisomy 21. These ethical
principles have important clinical
implications for risk assessment for
trisomy 21 via available screening and
diagnostic tools and management of
individual pregnancies. The purpose of
this paper is to identify those implications. First, we describe these ethical
principles and their implementation in
the informed consent process. Second,
we identify the ethics of routinely
offering first trimester risk assessment
or diagnostic testing in centers that
are qualified to do so and the ethical
flaws of withholding the results of first
trimester risk assessment until the second trimester.
THREE ETHICAL
PRINCIPLES
Beneficence and its corollary, nonmaleficence can be simply described as
the responsibility of physicians, acting
with integrity, to do good and to
avoid harm. The ethical principle of
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AMERICAN JOURNAL OF MEDICAL GENETICS PART C (SEMINARS IN MEDICAL GENETICS): DOI 10.1002/ajmg.c
Beneficence and its corollary,
nonmaleficence can be
simply described as the
responsibility of physicians,
acting with integrity, to do
good and to avoid harm.
beneficence directs the physician to
identify and implement clinical management that is reliably expected, on the
basis of the best available evidence, to
result in a greater balance of clinical
goods over clinical harms (risks) for the
patient [Chervenak and McCullough,
2005; ACOG, 2002].
Respecting a patient’s autonomy,
maintains her right to refuse or choose
recommended treatments or tests. The
ethical principle of respect for autonomy
directs the physician to identify and
implement clinical management that
is reliably expected in the patient’s
judgment to result in a greater balance
of clinical and other goods that are
important to the patient over clinical
and other harms (risks) that the
patient wants to avoid [ACOG, 2002;
Chervenak and McCullough, 2005].
Justice relates to the fair distribution
of the benefits and burdens of screening.
Put more precisely, the ethical principle
of justice directs the physician to prevent
exploitation, that is, an outcome in
which only a very few have access to
significant benefit and the many experience only burden without the opportunity to experience off-setting benefit.
The obligation to avoid exploitation
shapes the ethics of the informed consent process and appropriate counseling
[ACOG, 2002; Chervenak and McCullough, 2005].
Implications of Beneficence
for Risk Assessment
Physicians are obligated by the ethical
principle of beneficence to seek a greater
balance of clinical goods over clinical
harms for patients. Using sound clinical
judgment and professional integrity,
physicians should identify and offer
clinical treatments and screening tests
in the general population that can
achieve such a balance.
In order to engage in a discussion
with a patient regarding first trimester
risk assessment, the first clinical ethical
question to ask is whether it is medically
reasonable. If it were not, physicians
would have no ethical obligation to offer
it to pregnant women.
Conversely, if first trimester risk
assessment is medically reasonable,
which has been proven in international
studies, [Nicolaides et al., 1992; Snijders
if first trimester risk assessment
is medically reasonable,
which has been proven in
international studies,
et al., 1998; Wald et al., 2003; Wapner
et al., 2003; Nicolaides, 2004;
Malone et al., 2005] then the reasonable person standard requires disclosure of it to pregnant women in the
informed consent process for the
then the reasonable person
standard requires disclosure
of it to pregnant women in
the informed consent process
for the management of
their pregnancies
management of their pregnancies
[Chervenak et al., 2005].
These studies demonstrated that
first trimester risk assessment, using
ultrasound and biochemistry in highquality centers, is medically reasonable,
[Nicolaides et al., 1992; Snijders et al.,
1998; Wald et al., 2003; Wapner et al.,
2003; Nicolaides, 2004; Malone et al.,
2005] especially if provision of its results
reduces the incidence of invasive tests
and thus unnecessary pregnancy loss. It
follows from the ethics of informed
consent that obstetricians have an ethical
obligation to offer pregnant high-quality
first trimester risk assessment as a
ARTICLE
medically reasonable component of the
management of their pregnancies.
Many authors have described the
benefits of first trimester screening.
Chasen and Skupski [2003] noted
potential benefits and harms of first
trimester risk assessment. Benefits with
early disclosure of results included
improved aneuploid screening compared to age alone, for multiple gestations, association with cardiac and other
congenital malformations, gestational
age dating, and establishment of chorionicity in multiple gestations. The risks
stem from poor information from poor
technique and lack of quality control,
which would also affect integrated
and sequential screening, too, by means
of propagation of error [Chasen and
Skupski, 2003]. Since these risks can be
reduced by limiting risk assessment to
centers of excellence, the ethical principle of beneficence requires that risk
assessment be performed in such centers.
The American College of Obstetricians and Gynecologists and the
American College of Medical Genetics
both still recommend invasive diagnostic
testing for aneuploidy in women aged
35 or older at time of delivery. However,
offering first trimester risk assessment to
all pregnant women, even those 35 years
and older, is supported by the American
College of Obstetricians and Gynecologists and the National Institute of Child
Health and Human Development, provided that adequate training and quality
are assured [ACOG, 2004; Reddy and
Mennuti, 2006. Alternatively, patients
could choose no screening test or
proceed directly to an invasive test.
First trimester risk assessment with
immediate disclosure is a medically reasonable choice for aneuploidy screening
in beneficence-based clinical judgment
First trimester risk assessment
with immediate disclosure is
a medically reasonable choice
for aneuploidy screening in
beneficence-based clinical
judgment
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AMERICAN JOURNAL OF MEDICAL GENETICS PART C (SEMINARS IN MEDICAL GENETICS): DOI 10.1002/ajmg.c
[ACOG, 2004; Chervenak and McCullough, 2005; Nicolaides et al., 2005;
Reddy and Mennuti, 2006]. The integrated screen offers a marginal increase
in sensitivity and a decrease in false
positive screens. However, the benefits
of second trimester disclosure are offset
by later reassurance or later decision
making for invasive testing and possible
termination of pregnancy, at a time
when fetal kicks may be felt and
the termination may not be performed
as discretely. As first trimester risk
assessment is an acceptable means of
aneuploidy screening and integrated
screening is not clearly overall clinically
superior, nondirective counseling of
patients desiring screening requires
the physician to present all options to
patients and allow the best test for
that individual to be selected by the
individual [Berkowitz et al., 2006].
According to the American College
of Obstetricians and Gynecologists:
‘‘although first-trimester screening for
Down syndrome and trisomy 18 is an
option, it should be offered only if the
following criteria can be met:
‘‘Appropriate ultrasound training
and ongoing quality monitoring
programs are in place. Sufficient
information and resources are
available to provide comprehensive counseling to women regarding the different screening options
and limitations of these tests. Access
to an appropriate diagnostic test is
available when screening test results
are positive.’’ [ACOG, 2004].
These standards must be upheld in all
first trimester risk assessment schemes
involving nuchal translucency measurement, that is, integrated and sequential
screening programs, too.
In addition, offering aneuploidy
detection via invasive diagnostic procedures such as CVS and amniocentesis
to all pregnant women is ethically
justifiable. As women under the age of
35 constitute the larger population having children—more neonates with T21
are born in this population. Thus, not
offering a diagnostic test to these women
negates their autonomy and exploits
them based on their age, while ignoring
that all women do carry some risk of
carrying an affected child [Druzin et al.,
1993].
It is important to recognize that
aneuploidy screening and detection
involves sensitive personal beliefs and
perceived societal benefit should not
completely overpower individual choice.
Implications of Respect for
Autonomy for Risk Assessment
In the context of Down syndrome
screening, this is clearly an era of
women’s choice. Previously, a woman’s
a priori risk for fetal Down syndrome
was solely based on her age, a screening
strategy with only 30% sensitivity. The
American College of Obstetricians and
Gynecologists recommends invasive
diagnostic testing for all women over
the age of 35 [ACOG, 2001]. Recent
recommendations are to offer first trimester risk assessment where available,
to women of advanced maternal age
[ACOG, 2001]. The credibility of first
trimester combined screening has been
supported by large international trials
[Nicolaides et al., 1992; Snijders
et al., 1998; Wald et al., 2003; Wapner
et al., 2003; Nicolaides, 2004;
Malone et al., 2005]. However, the ideal
triaging of first trimester screening
results and timing of disclosure lacks
consensus.
Similar to second trimester serum
screening permutations, which evolved
into improved screening efficacy, first
trimester risk assessment programs
are effective, evolving, and medically
reasonable screening tools. As practitioners debate the relative merits of
integrated, sequential, step-wise, and
contingent screening protocols, the
absence of clear clinical superiority of
any one of them means that patient
opinions cannot be ignored and
should be factored into these discussions.
It would therefore be paternalistic to
assume all patients would desire the
integrated test, despite its slight incremental increased sensitivity and
ability to reduce the false-positive rate
[Berkowitz et al., 2006]. In a competent
individual, autonomy encompasses a
patient’s values, beliefs, interests, social
101
constructs, and medical and nonmedical
issues [Chervenak and McCullough,
In a competent individual,
autonomy encompasses a
patient’s values, beliefs,
interests, social constructs, and
medical and nonmedical issues
1992]. Implicit in respecting a patient’s
autonomy is recognition of her negative
rights to noninterference, that is, the
right to refuse offered or recommended
clinical management. Thus, offering only
Implicit in respecting a
patient’s autonomy is
recognition of her negative
rights to noninterference,
that is, the right to refuse
offered or recommended
clinical management.
integrated screening or a screening
triage that leads to a default-integrated
pathway does not integrate a patient’s
individual wishes. In addition, patients
may decline screening and/or move
directly to invasive diagnostic testing,
which are options in autonomy and
beneficence-based clinical judgement
[Druzin et al., 1993].
There is evidence that many
women who desire aneuploidy screening desire earlier availability of results
and that first trimester risk assessment
influences their decision regarding invasive diagnostic testing. In a survey of
Dutch women who were undergoing
second trimester serum screening, the
majority (76%) stated that first trimester
screening would have been preferable
due to facilitation of pregnancy termination and earlier reassurance. Additionally, 44% of women who underwent
CVS stated that results of first trimester
testing would have influenced their
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AMERICAN JOURNAL OF MEDICAL GENETICS PART C (SEMINARS IN MEDICAL GENETICS): DOI 10.1002/ajmg.c
decision to undergo an invasive diagnostic test [Kornman et al., 1997].
Similarly, Nicolaides et al. [2005]
demonstrated that women were able to
make an informed choice based on first
trimester risk assessment results. Invasive
testing was chosen and performed in
proportion to the degree of aneuploidy
risk predicted. First trimester risk assessment can contribute to a reduction in
invasive diagnostic procedures. Zoppi
et al. [2001] compared two groups of
women of advanced maternal age before
and after first trimester risk assessment
was introduced. In this high-risk
population, first trimester risk assessment significantly reduced the number
of invasive diagnostic procedures
and increased the number of aneuploid
cases detected in the first trimester.
Zoppi et al. compared two
groups of women of advanced
maternal age before and after
first trimester risk assessment
was introduced. In this
high-risk population, first
trimester risk assessment
significantly reduced the
number of invasive diagnostic
procedures and increased the
number of aneuploid cases
detected in the first trimester.
Wray et al. [2005] also showed a
significant reduction in invasive testing
after the introduction of first trimester
screening in patients of advanced
maternal age. Chasen et al. [2004]
similarly demonstrated that first
trimester risk assessment disclosure
reduced the frequency of diagnostic
testing which could be extrapolated to
fewer procedure-related miscarriages.
In England, Spencer and Aitken
[2004] presented women with different
options regarding first trimester risk
assessment disclosure. The majority,
75%, chose early disclosure within 2–
3 days. In Australia, Mulvey and Wallace
[2003] interviewed 100 women at their
first antenatal visit after receiving counseling regarding the natural history of
Down syndrome pregnancies and the
abilities and limitations of prenatal
screening and diagnostic testing. They
found that 74 patients preferred first
trimester over second trimester screening, even with the understanding that
the fetuses that were identified as
abnormal could miscarry naturally. In a
later study from the same center, women
undergoing prenatal genetic counseling
were assessed by a questionnaire and
older women stated that a higher detection rate was more important than a low
screen-positive rate. These women did
not wish to miss a diagnosis of Down
syndrome and preferred the potential
loss of a normal fetus [Mulvey et al.,
2003].
De Graaf et al. [2002] showed that
76% of patients who received pre-test
counseling desired first trimester risk
assessment with ultrasound and biochemistry. These patients were older
and found the risk of miscarriage more
acceptable than the risk of delivering a
baby with trisomy 21. These findings are
consistent with those in our study, in
which a preference for early disclosure,
69.3% of patients undergoing first trimester ultrasound and biochemistry, was
associated with both older age and a
greater likelihood of terminating a fetus
with trisomy 21 [Sharma et al., 2005].
The studies from Mulvey et al.
[2006] in Australia and de Graaf et al.
[2002] from The Netherlands both
demonstrate an association between
background knowledge of screening
and diagnostic tests and Down syndrome
and preference for early disclosure.
These studies in conjuction with the
United States studies by Wray et al.
[2005] and Sharma et al. [2005] and
Spencer and Aitken [2004] in England,
display a common significant preference,
by at least 70% of women, for early
disclosure of first trimester aneuploidy
risk assessment results.
Management of a pregnancy
could involve a decision to continue
or terminate one’s pregnancy—an
autonomy-based decision. A woman’s
ARTICLE
decision is also influenced by her values
and beliefs, including religious and
upbringing, economic and family
circumstances, and the views of those
whose judgments she values. Physicians
do not have special competence with
regard to such decisions because they
involve not just clinical concerns but
broader human and social concerns.
Medically and ethically, physicians do
play an important role in the enhancement of women’s autonomy by providing them the best available information
about medically reasonable alternatives
[Chervenak et al., 2005].
Offering first trimester risk assessment supports women’s autonomy and
we dispute the routine withholding of
first trimester risk assessment. Withholding this information is paternalistic,
denies women critical information, and
conflicts with the principle of justice as
withholding exploits pregnant women.
They are then denied the benefit of early
decision about invasive testing and
possible termination, without offsetting
benefit, because the incremental
improvement in the integrated scheme
is small.
Implications of Justice for
Risk Assessment
The ethical principle of justice refers to
fairness to the individual and physician
and the impact on society. Justice is a
population-based ethical principle, in
contrast to the individual-patient focus
of respect for autonomy and beneficence. Justice obligates the physician not
to exploit a population of patients.
Exploitation in a patient population
occurs when a small number benefit
but the great majority bear the iatrogenic
burden with no off-setting benefit.
Given the fact that first trimester risk
assessment with ultrasound and biochemistry provides acceptable detection
rates at a 5% false-positive rate and
permits earlier reassurance or allows
individuals to proceed with timely
invasive diagnosis and safer termination
of pregnancy procedures, justice-based
considerations support the use of this
screening modality and are violated
when women are denied this option.
ARTICLE
AMERICAN JOURNAL OF MEDICAL GENETICS PART C (SEMINARS IN MEDICAL GENETICS): DOI 10.1002/ajmg.c
Given the fact that first
trimester risk assessment with
ultrasound and biochemistry
provides acceptable detection
rates at a 5% false-positive rate
and permits earlier reassurance
or allows individuals to
proceed with timely invasive
diagnosis and safer termination
of pregnancy procedures,
justice-based considerations
support the use of this screening
modality and are violated when
women are denied this option.
Broadly applying routine use of
the integrated screen and withholding
results of first trimester information is
not ethically sound, as doing so exploits
pregnant women by violating the
principle of justice. Although a marginal
increase in precision in risk assessment
with a lower false-positive rate can be
achieved with this strategy, it should not
be applied without patient choice. It can
no longer be assumed that the integrated
risk assessment is the only medically
reasonable form risk assessment [Wald
et al., 2003; Malone et al., 2005;
Nicolaides et al., 2005; Wenstrom,
2005; Berkowitz et al., 2006; Reddy
and Mennuti, 2006] as the other strategies are also acceptable, such as the
combined first trimester risk assessment,
integrated serum screen, second trimester quadruple screen, and sequential
first and second trimester screening
either performed in a step-wise or
contingent fashion. If a woman prefers
more precise risk assessment by incorporating first and second trimester
screening results, she should be provided
the first trimester risk assessment, and
then she is certainly free to postpone
a decision about invasive testing
pending second trimester results. Even
certain proposed formats of contingent
screening would allow for first trimester
disclosure with an option to obtain
second trimester integrated results.
Informed consent requires that patients
are aware of the choices available to them
and the possible risks of an increased
false-positive screen and the benefits
of earlier disclosure of results for reassurance, pregnancy management, or
consideration of invasive diagnostic testing. Withholding first trimester results as
a routine practice violates the ethical
principle of informed consent and substitutes paternalism.
As pointed out above in our consideration of the implications of respect
for autonomy, the majority of patients
across different geographic regions
expressed a preference towards earlier
disclosure of results. Although the
screening efficacy of the integrated
screen (8 pregnancy losses per 100,000
patients screened) is numerically better
than that of the combined first trimester
risk assessment and second trimester
maternal serum quadruple screen (each
is 66 pregnancy losses per 100,000
patients screened), [Wenstrom, 2005]
the emotional and personal preferences
can not be quantified as easily.
The principle of justice also requires
nondirective counseling about alternatives for risk assessment, as well as
invasive testing. Patients should therefore be presented with options for
screening and invasive testing and
allowed to select the best choice for
their needs. Withholding this choice
exploits women.
Implications for the Informed
Consent Process
Appropriate counseling is necessary for
patients to choose what they judge to be
the best screening paradigm for their
individual situation. The informed consent process is the clinical tool that
implements the ethical principles of
beneficence and respect for autonomy
in the decision-making process with
patients about the clinical management
of their pregnancies.
As Spencer and Aitken [2004]
showed, 24% of patients desired integrated screening. Physicians ethically
should acknowledge competent adults
103
or alternatively an appointed surrogate as
able to make an informed choice based
on discussion of risks, benefits and
alternative treatments, and ability to
decline treatment. Patients’ understanding of Down syndrome and screening
versus diagnostic testing are important
aspects to address in the informed
consent process. Our data demonstrated that educated patients in the United
States can develop a good understanding
of both screening and Down syndrome,
which is critical to the informed
consent process [Sharma et al., 2005].
In addition, both de Graaf et al. [2002]
and Mulvey and Wallace [2006]
studies showed an association with pretest counseling and patient-informed
choice.
In the first step of the informed
consent process, the ethical principle of
beneficence directs the physician to
identify all medically reasonable alternatives for the management of the
patient’s pregnancy, that is, those alternatives for which there is an evidencebased expectation that they will, on
balance, clinically benefit the patient.
This involves expert clinical judgment
that conforms to the discipline of
evidence-based clinical reasoning.
In the second step of the informed
consent process, the ethical principle of
respect for autonomy directs the physician to present all of the medically
reasonable alternatives to the patient,
along with information about their
clinical benefits and risks. The rule of
thumb is that clinically salient information should be provided to the patient.
Doing so meets the ethically accepted reasonable person standard for
disclosure.
In the third step of the informed
consent process, the patient exercises
her autonomy by understanding this
information, especially the nature
and expected outcomes of different
alternatives (cognitive understanding),
appreciating that the outcomes described could happen to her (appreciation), and assessing information on the
basis of her values and beliefs (evaluative
understanding). All adult patients should
be presumed to have these capacities.
The burden of proof is on the physician
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AMERICAN JOURNAL OF MEDICAL GENETICS PART C (SEMINARS IN MEDICAL GENETICS): DOI 10.1002/ajmg.c
to establish that the patient’s decisionmaking capacity in one or more of these
domains is significantly impaired.
In the fourth step of the informed
consent process, the physician may make
a recommendation of an alternative,
when evidence-based reasoning supports it as clearly clinically superior
(directive counseling). In the absence
of such evidence-based clinical evaluation of alternatives, the physician should
refrain from making a recommendation
(non-directive counseling).
In the fifth step of the process, the
patient exercises her autonomy by
expressing her preference from among
the alternatives presented or rejects them
all. The ethical principle of respect for
autonomy directs the physician to protect the patient from substantially controlling or coercive influences on the
patient’s expression of her preference.
CONCLUSION
The ethical principles of respect for
patient autonomy, beneficence, justice,
and the informed consent are essential
components of first trimester risk assessment for trisomy 21. These principles
support the routine counseling and
offering of first trimester risk assessment
in centers that are qualified to provide it.
These standards also rule out as ethically
unacceptable techniques of risk assessment that routinely fail to disclose the
results of first trimester risk assessment
when they become available to women
who desire early disclosure of results.
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second, disclosure, patients, trimester, diagnostika, early, testing, ethical, trisomy, screening, first, choice, versus, considerations, assessment, risk
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