Review
article
Outcome
of
cesarean
scar
pregnancy
according
to
gestational
age
at
diagnosis:
A
systematic
review
and
meta-analysis
Ilan
Timor-Tritsch
a,
Danilo
Buca
b,
Daniele
Di
Mascio
c,
Giuseppe
Cali
d,
Alice
D
’Amico
b,
Ana
Monteagudo
e,
Sara
Tinari
b,
Maddalena
Morlando
f,
Luigi
Nappi
g,
Pantaleo
Greco
h,
Giuseppe
Rizzo
i,j,
Marco
Liberati
b,
Jose-Palacios-Jaraquemada
k,
Francesco
D
’Antonio
b,*
a
DepartmentofObstetricsandGynecology,DivisionofMaternal-FetalMedicine,NewYorkUniversitySOM,NewYork,NY,USA
b
CenterforFetalCareandHigh-RiskPregnancy,DepartmentofObstetricsandGynecology,DepartmentofObstetricsandGynecology,UniversityofChieti,
Chieti,Italy
c
DepartmentofMaternalandChildHealthandUrologicalSciences,SapienzaUniversityofRome,Italy
d
DepartmentofObstetricsandGynecology,AziendaOspedalieraVillaSofiaCervello,Palermo,Italy
e
DepartmentofObstetrics,GynecologyandReproductiveScience,IcahnSchoolofMedicineatMountSinai,NewYork,NY,USA
fDepartmentofWoman,Child,andGeneralandSpecializedSurgery,UniversityofCampania"LuigiVanvitelli",Naples,Italy
g
DepartmentofMedicalandSurgicalSciences,InstituteofObstetricsandGynaecology,UniversityofFoggia,Italy
h
DepartmentofMorphology,SurgeryandExperimentalMedicine,InstituteofObstetricsandGynaecology,UniversityofFerrara,Italy
i
UniversitàdiRomaTorVergata,DivisionofMaternalFetalMedicine,OspedaleCristoRe,Rome,Italy
j
TheFirstI.M.SechenovMoscowStateMedicalUniversity,DepartmentofObstetricsandGynecology,Moscow,Russia
k
CentreforMedicalEducationandClinicalResearch(CEMIC),UniversityHospital,BuenosAires,Argentina
ARTICLE INFO Articlehistory: Received1September2020 Accepted11November2020 Keywords: CSP
Cesareanscarpregnancy
PAS
Placentaaccreta
Placentaaccretaspectrumdisorders
Hemorrhage
Uterinerupture
Hysterectomy
ABSTRACT
Objective:Theassociationbetweenthemostseveretypesofplacentaaccretaspectrumdisordersand caesareanscarpregnancy(CSP)posesthequestionofwhetherearlydiagnosismayimpacttheclinical outcomeoftheseanomalies.Theaimofthisstudyistoreporttheoutcomeofcesareanscarpregnancy (CSP)diagnosedintheearly(9weeks)versuslate(>9weeks)firsttrimesterofpregnancy. Studydesign:Medline,EmbaseandClinicaltrail.govdatabasesweresearched.Studiesincludingcasesof CSPwithanearly(9weeksofgestation)comparedtoalate(>9weeks)firsttrimesterdiagnosisofCSP, followedbyimmediatetreatment,wereincludedinthissystematicreview.Theprimaryoutcomewasa compositemeasureofseverematernalmorbidityincludingeitherseverefirsttrimesterbleeding,need forbloodtransfusion,uterineruptureoremergencyhysterectomy.Thesecondaryoutcomeswerethe individualcomponentsoftheprimaryoutcome.Random-effectmeta-analyseswereusedtocombine data.
Results:Thirty-sixstudies(724womenwithCSP)wereincluded.Overall,compositeadverseoutcome complicated5.9%(95%CI3.5 9.0)ofCSPdiagnosed9weeksand32.4%(95%CI15.7 51.8)ofthose diagnosed>9weeks.Massivehemorrhageoccurredin4.3%(95%CI2.3 7.0)ofwomenwithearlyandin 28.0%(95%CI14.1 44.5)ofthosewithlatefirsttrimesterdiagnosisofCSP,whilethecorresponding figuresfortheneedforbloodtransfusionwere1.5%(95%CI0.6 2.8)and15.8%(95%CI5.5 30.2) respectively.Uterineruptureoccurredin2.5%(95%CI1.2 4.1)ofwomenwithaprenataldiagnosisof CSP9 weeksand in7.5% (95% CI2.5 14.9) of thosewithCSP>9 weeks,while anemergency interventioninvolvinghysterectomywasrequiredin3.7%(95%CI2.2 5.4)and16.3%(95%CI5.9 30.6) respectively.Whencomputingtherisk,earlydiagnosisofCSPwasassociatedwithasignificantlylower riskofcompositeadverseoutcome,(OR:0.14;95%CI0.1 0.4p<0.001).
Conclusions:EarlyfirsttrimesterdiagnosisofCSPisassociatedwithasignificantlylowerriskofmaternal complications,thussupportingapolicyofuniversalscreeningfortheseanomaliesinwomenwithaprior cesareandeliveryalthoughthecost-effectivenessofsuchpolicyshouldbetestedinfuturestudies.
©2020PublishedbyElsevierB.V.
*Correspondingauthorat:CenterforFetalCareandHigh-RiskPregnancy,DepartmentofObstetricsandGynecology,UniversityofChieti,ViadeiVestini31,66100Chieti,
Italy.
E-mailaddress:[email protected](F.D’Antonio).
https://doi.org/10.1016/j.ejogrb.2020.11.036
0301-2115/©2020PublishedbyElsevierB.V.
Contents
lists
available
at
ScienceDirect
European
Journal
of
Obstetrics
&
Gynecology
and
Reproductive
Biology
Contents
Introduction ... 54
Materialandmethods ... 54
Protocol,eligibilitycriteria,informationsourcesandsearch ... 54
Studyselection,datacollectionanddataitems ... 54
Visualizationofanemptyuterinecavity ... 54
Aclosedcervixandemptyendocervicalcanal ... 54
Statisticalanalysis ... 55
Results ... 55
Studyselectionandcharacteristics ... 55
Synthesisoftheresults... 56
Discussion ... 56
Mainfindings ... 56
Strengthsandlimitations ... 56
Implicationsforclinicalpractice ... 57
Conclusions ... 58
Funding ... 58
DeclarationofCompetingInterest ... 58
Acknowledgments ... 58
References ... 58
Introduction
The
rise
in
the
cesarean
delivery
(CD)
rate
over
the
last
three
decades
has
led
to
a
massive
increase
in
the
incidence
of
peculiar
iatrogenic
complications,
including
placental
accreta
spectrum
(PAS)
disorders
and
cesarean
scar
pregnancy
(CSP)
as
its
precursor.
[
1
–12
]
Prenatal
diagnosis
of
these
anomalies
at
any
gestational
age
is
associated
with
improved
maternal
outcome,
by
allowing
treatment
in
centers
with
high
expertise
in
surgical
management.
[
13
–21
]
The
recent
reported
association
between
the
most
severe
types
of
PAS
and
cesarean
scar
pregnancy
(CSP)
poses
the
question
of
whether
early
diagnosis
may
impact
the
clinical
outcome
of
these
anomalies.
[
22
–25
]
CSP
is
commonly
diagnosed
on
ultrasound
as
the
gestational
sac
or
trophoblast
within
the
dehiscence/niche
of
the
previous
cesarean
section
scar
or
implanted
on
top
of
it,
associated
with
the
visualization
of
an
empty
uterine
cavity,
a
closed
cervix
and
empty
endocervical
canal
[
4
–6
,
8
].
Gestational
age
at
diagnosis
of
CPS
may
represent
another
peculiar
issue,
since
early
diagnosis
of
CSP
appears
to
be
fundamental,
as
the
volumeof
the
mass,
its
vascularity
and
gestational
age
at
diagnosis
are
among
the
main
determinants
of
the
pregnancy
outcome.
[
3
,
6
,
11
,
20
]
More
importantly,
recent
evidences
highlight
the
role
of
early
first
trimester
ultrasound,
not
only
in
detecting
the
most
severe
complication
arising
from
a
CSP
-
the
occurrence
of
PAS
-
but
also
in
predicting
their
surgical
outcome
[
22
].
We
have
recently
proposed
that
a
policy
of
early
(5 7
weeks)
transvaginal
ultrasound
screening
of
women
with
a
prior
CD
would
allow
a
prompt
and
timely
detection
and
treatment
of
a
possible
CSP,
potentially
minimizing
the
burden
of
surgical
morbidities.
[
22
]
However,
the
above
observation
was
based
upon
collective
authors
’
experience
that
early
first
trimester
diagnosis
of
CSP
is
associated
with
a
lower
risk
of
sever
maternal
symptoms
requiring
emergency
intervention,
including
hemorrhage
and
uterine
rupture.
Thus,
the
aim
of
this
systematic
review
was
to
report
the
incidence
of
maternal
morbidity
in
women
with
early
(
9
weeks)
compared
to
late
(
>9
weeks)
first
trimester
diagnosis
of
CSP.
Material
and
methods
Protocol,
eligibility
criteria,
information
sources
and
search
This
review
was
performed
according
to
a
protocol
designed
a
priori
and
recommended
for
systematic
review
[
26
–28
]
Medline,
Embase
and
ClinicalTrials.gov
databases
were
searched
electroni-cally
on
July
2020
utilizing
combinations
of
the
relevant
medical
subject
heading
(MeSH)
terms,
key
words,
and
word
variants
for
“cesarean
scar
pregnancy
”
and
“outcome.”
Reference
lists
of
relevant
articles
and
reviews
were
hand
searched
for
additional
reports.
PRISMA
guidelines
were
followed
[
29
,
30
].
Study
selection,
data
collection
and
data
items
Inclusion
criteria
were
studies
including
cases
of
CSP
with
early
(
9
weeks
of
gestation)
compared
to
late
(
>9
weeks)
first
trimester
diagnosis
of
CSP,
followed
by
immediate
treatment
The
primary
outcome
was
a
composite
measure
of
severe
maternal
morbidity
including
Severe
first
trimester
bleeding,
de
fined
as
an
estimated
blood
loss
>
500
mL
Need
for
blood
transfusion
Uterine
rupture
Emergency
hysterectomy
Emergency
surgical
treatment
The
secondary
outcomes
were
the
individual
component
of
the
primary
outcome.
CSP
was
de
fined
as
the
gestational
sac
or
trophoblast
within
the
dehiscence/niche
left
behind
by
the
previous
CD
scar
or
implanted
on
top of
the
scar and
diagnosed
according to the
following criteria [
11
]:
Visualization
of
an
empty
uterine
cavity
1
Detection
of
the
placenta
and/or
a
gestational
sac
embedded
in
the
hysterotomy
scar.
2
A
triangular
gestational
sac
that
fills
the
niche
of
the
scar
(usually
before
7
weeks).
3
A
thin
(1 3
mm)
or
absent
myometrial
layer
between
the
gestational
sac
and
the
bladder.
A
closed
cervix
and
empty
endocervical
canal
4
The
presence
of
embryonic/fetal
pole
and/or
yolk
sac
with
or
without
heart
activity.
5
The
presence
of
a
prominent
and
at
times
rich
vascular
pattern
at
or
around
the
chorionic
sac
and
the
placenta
Two
authors
(DB,
FDA)
reviewed
all
abstracts
independently.
Agreement
regarding
potential
relevance
was
reached
by
consen-sus
with
a
third
reviewer
(FDA);
full
text
copies
of
those
articles
were
obtained,
and
the
same
two
reviewers
independently
extracted
relevant
data
regarding
study
characteristics
and
pregnancy
outcome.
Inconsistencies
were
discussed
and
consen-sus
was
reached
or
the
dispute
was
resolved
by
discussion
with
another.
If
more
than
one
study
was
published
for
the
same
cohort
with
identical
endpoints,
the
report
containing
the
most
compre-hensive
information
on
the
population
was
included
to
avoid
overlapping
populations.
Only
full
text
articles
were
considered
eligible
for
the
inclusion.
Conference
abstracts
and
single
case
reports
were
excluded
to
avoid
publication
bias.
Studies
published
before
the
year
2000
were
not
included,
as
we
considered
that
advances
in
prenatal
imaging
techniques,
improvements
in
the
diagnosis
and
manage-ment
of
CSP
make
these
less
relevant.
Quality
assessment
of
the
included
studies
was
performed
using
the
Newcastle-Ottawa
Scale
(NOS).
[
31
]
According
to
NOS,
each
study
is
judged
on
three
broad
perspectives:
the
selection
of
the
study
groups;
the
comparability
of
the
groups;
and
the
ascertainment
outcome
of
interest.
Assessment
of
the
selection
of
a
study
includes
the
evaluation
of
the
representativeness
of
the
exposed
cohort,
selection
of
the
non-exposed
cohort,
ascertain-ment
of
exposure
and
the
demonstration
that
outcome
of
interest
was
not
present
at
start
of
study.
Assessment
of
the
comparability
of
the
study
includes
the
evaluation
of
the
comparability
of
cohorts
on
the
basis
of
the
design
or
analysis.
Finally,
the
ascertainment
of
the
outcome
of
interest
includes
the
evaluation
of
the
type
of
the
assessment
of
the
outcome
of
interest,
length
and
adequacy
of
follow-up.
According
to
NOS,
a
study
can
be
awarded
a
maximum
of
one
star
for
each
numbered
item
within
the
Selection
and
Outcome
categories.
A
maximum
of
two
stars
can
be
given
for
Comparability
[
31
].
Statistical
analysis
For
the
quanti
fication
of
the
incidence
of
outcomes
explored,
meta-analyses
of
proportions
using
random
effects
model
were
used
to
combine
data.
Funnel
plots
displaying
the
outcome
rate
from
individual
studies
versus
their
precision
(1/standard
error)
were
carried
out
with
an
exploratory
aim.
Tests
for
funnel
plot
asymmetry
were
not
used
when
the
total
number
of
publications
included
for
each
outcome
was
less
than
ten.
In
this
case,
the
power
of
the
tests
is
too
low
to
distinguish
chance
from
real
asymmetry.
Between-study
heterogeneity
was
explored
using
the
I
2statistic,
which
represents
the
percentage
of
between-study
variation
that
is
due
to
heterogeneity
rather
than
chance.
[
32
–34
]
All
analyses
were
performed
using
StatsDirect
Ltd.
StatsDirect
statistical
software
(England:
StatsDirect
Ltd.
2013).
Results
Study
selection
and
characteristics
A
total
of
865
articles
were
identi
fied,
96
were
assessed
with
respect
to
their
eligibility
for
inclusion
(Supplementary
Table
S1)
and
37
studies
included
in
the
systematic
review
(
Table
1
,
Fig.
1
).
Table1
Generalcharacteristicsofthestudiesincludedinthepresentsystematicreview.
Author Year Country Studydesign Periodanalyzed(y) GAdiagnosis Cases(n)
Lopez-Giron[35] 2020 Colombia Retrospective 2010 2019 5 16.5w 12
Li[36] 2019 China Retrospective 2007 2018 <9w 101
Naeh[37] 2019 Israel Retrospective 2014 2018 6 10w 12
Orhan[38] 2019 Turkey Retrospective 2011 2017 5 10w 31
Tanaka[39] 2019 Australia Retrospective 2008 2017 5 13w 28
Grechukhina[40] 2018 US Retrospective 2013 2018 36 56d 30
Jachymski[41] 2018 Poland Retrospective 2010 2017 6 12w 24
Karahasanoglu[42] 2018 Turkey Retrospective 2009 2013 <8w 13
Kim[43] 2018 Korea Retrospective 2003 2015 6.5+/-1.1w 58
Kim(2)[44] 2018 Korea Retrospective 2009 2015 4.8 8.5w 49
Monteagudo[45] 2018 USA Retrospective NS 5 10w 36
Sel[46] 2018 turkey Retrospective 2015 2018 <8w 12
Shafqat[47] 2018 Pakistan Retrospective 2002 8,612w 3
Hong[48] 2017 China Retrospective 2014 2016 5128+\ 9,19d 152
Washburn[49] 2017 USA Retrospective 2000 2012 4.6 11.1w 23
Gao[50] 2016 China Retrospective 2009 2012 7.3(5.4 12)w 9
Boza[51] 2016 Turkey Retrospective 2013 2014 5.3 7.3w 4
Ouyang[52] 2015 China Retrospective 2011 2015 (5+3–7+0)w 6
Riaz[53] 2015 UnitedStates Retrospective 2008 2015 (5+2 10+0)w 20
Rheinboldt[54] 2015 USA Retrospective NS 7 12w 3
Wang(2)[55] 2015 China Retrospective 2009 2013 6 11w 11
Yang[56] 2014 SouthKorea Retrospective NS 6.7(6 7)w 3
Zhang[57] 2013 China Retrospective 2005 2011 5 8w 10
Uysal[58] 2013 Turkey Retrospective NS 6 12w 7
Zhang(2)[59] 2013 China Retrospective 2005 2010 6.6(6.2 13.7)w 17
He[60] 2011 China Retrospective 2009 2010 7 9w 6
Sadeghi[61] 2010 UnitedStates Retrospective 2007 2008 6/9w 4
deVaate[62] 2010 TheNetherlands Retrospective NS 5+1 6+6w 4
Muraij[63] 2009 Japan Retrospective NS 5w 3
Michener[64] 2009 Australia Retrospective 2002 2007 6.8(5.5 11.5)w 9
Yan[65] 2007 China Retrospective NS 7.5(5 10)w 4
Wang[66] 2006 Taiwan Retrospective 1999 2004 6 11w 11
Sugawara[67] 2005 Japan Retrospective NS 5 7w 3
Maymon[68] 2004 Israel Retrospective 1995 2002 7(6 9)w 8
Seow[69] 2004 Taiwan Retrospective 1995 2002 5.5 12.4w 6
Seow(2)[70] 2004 Taiwan Retrospective 1995 2000 5 12w 12
Jurkovic[71] 2003 UnitedKingdom Retrospective NS 4 23w 18
[
35
–71
]
These
37
studies
(724
pregnancies)
reported
the
occur-rence
of
maternal
outcome
in
women
with
early
(
9
weeks)
compared
to
late
(
>9
weeks)
first
trimester
diagnosis
of
CSP.
Quality
assessment
of
the
included
studies
performed
using
Newcastle-Ottawa
Scale
(NOS)
for
cohort
studies
is
shown
in
Table
2
.
Most
of
the
included
studies
showed
an
overall
good
rate
about
the
selection
and
comparability
of
the
study
groups.
The
main
weaknesses
of
these
studies
were
their
retrospective
design,
small
sample
size,
lack
of
strati
fication
of
the
analysis
and
position
and
a
large
heterogeneity
in
gestational
age
at
diagnosis,
outcomes
observed
and
management
protocols.
Synthesis
of
the
results
Overall,
composite
adverse
outcome
complicated
5.9
%
(95
%
CI
3.5 9.0;
I
2:
47.7
%)
of
CSP
diagnosed
9
weeks
and
32.4
%
(95
%
CI
15.7 51.8;
I
2:
63.1
%)
of
those
diagnosed
>9
weeks.
Massive
hemorrhage
occurred
in
4.3
%
(95
%
CI
2.3 7.0;
I
2:
31.7
%)
of
women
with
early
and
in
28.0
%
(95
%
CI
14.1 44.5;
I
2:
49.8
%)
of
those
with
late
first
trimester
diagnosis
of
CSP,
while
the
corresponding
figures
for
the
need
for
blood
transfusion
were
1.5
%
(95
%
CI
0.6 2.8;
I
2:
0%)
and
15.8
%
(95
%
CI
5.5 30.2;
I
2:
28.8
%)
respectively.
Uterine
rupture
occurred
in
2.5
%
(95
%
CI
1.2 4.1;
I
2:
6.4
%)
of
women
with
a
prenatal
diagnosis
of
CSP
9
weeks
and
in
7.5
%
(95
%
CI
2.5 14.9;
I
2:
0%)
of
those
with
CSP
>
9
weeks,
while
an
emergency
intervention
involving
hysterectomy
was
required
in
3.7
%
(95
%
CI
2.2 5.4;
I
2:
0%)
and
16.3
%
(95
%
CI
5.9 30.6;
I
2:
45.3
%)
respectively.
Early
diagnosis
of
CSP
was
associated
with
a
signi
ficantly
lower
risk
of
composite
adverse
outcome,
(OR:
0.14;
95
%
CI
0.1 0.4
p
<
0.001,
I
2:
1.6
%).
Discussion
Main
findings
This
systematic
review
shows
that
CSP
diagnosed
in
the
early
stages
of
the
first
trimester
is
associated
with
a
lower
incidence
of
adverse
maternal
outcome,
including
massive
hemorrhage,
need
for
blood
transfusion,
uterine
rupture
and
emergency
hysterecto-my.
Conversely,
about
30
%
of
women
with
CSP
diagnosed
after
9
weeks
experienced
adverse
outcome.
Strengths
and
limitations
To
our
knowledge,
this
is
the
first
meta-analysis
assessing
the
role
of
gestational
age
at
diagnosis
of
CSP
on
maternal
outcome.
The
strengths
of
this
study
are
its
robust
methodology
for
identifying
all
possible
studies
for
inclusion,
assessing
data
quality
and
synthesizing
all
suitable
data
(
Table
3
).
The
small
number
of
cases
in
the
majority
of
the
included
studies,
their
retrospective
non-randomized
design,
different
periods
of
follow-up,
lack
of
strati
fication
of
the
analysis
according
to
the
serum
beta-hCG
levels,
size
and
position
of
the
gestational
sac
represent
the
main
limitations
of
the
present
systematic
review.
The
assessment
of
the
potential
publication
bias
was
also
problematic,
both
because
of
the
nature
of
outcome
(rates
with
the
left
side
limited
to
the
value
zero)
which
limits
the
reliability
of
funnel
plots,
and
because
of
the
scarce
number
of
individual
studies,
which
strongly
limits
the
reliability
of
formal
tests.
The
level
of
evidence
for
these
types
of
studies
is
very
low.
Another
limitation
is
the
selection
bias
in
the
studies,
as
in
most
of
the
included
studies
selection
of
the
patients
was
not
performed
in
a
controlled
or
randomized
manner.
Despite
this,
the
present
review
represents
the
best
published
estimate
of
the
occurrence
of
adverse
outcome
in
women
with
CSP
according
to
gestational
age
at
diagnosis,
that
is
an
extremely
important
issue,
as
counselling
of
parents
based
on
small
studies
that
are
subject
to
publication
bias
may
be
inadequate.
Implications
for
clinical
practice
Prenatal
diagnosis
of
PAS
and
CSP
is
fundamental,
as
it
is
associated
with
better
maternal
outcomes
mainly
by
allowing
referral
to
center
with
high
expertise
in
surgical
management
of
these
anomalies.
[
3
–7
,
12
,
13
,
21
]
The
overall
diagnostic
accuracy
of
ultrasound
in
detecting
such
anomalies,
especially
PAS,
has
been
reported
to
be
high
in
the
published
literature
but
with
a
large
heterogeneity
among
the
different
countries
[
4
,
14
–
16
,
22
,
24
,
25
,
72
].
Unfortunately,
detection
rate
of
these
anomalies
in
Scandinavia
is
low
with
less
than
30
%
of
cases
diagnosed
prenatally
according
to
a
recent
large
population
study
carried
out
in
the
Nordic
countries
[
73
].
This
low
detection
rate
highlights
the
need
for
a
proper
risk
strati
fication
and
introduction
of
better
screening
policies
aimed
at
identifying
women
at
higher
risk
of
these
anomalies.
The
recent
reported
association
between
CSP
and
both
the
most
severe
types
of
PAS
and
adverse
pregnancy
outcomes
in
a
subsequent
pregnancy
poses
the
question
of
whether
early
diagnosis
may
impact
the
clinical
outcome
of
these
anomalies.
[
10
,
11
,
74
]
Timely
first
trimester
diagnosis
of
CSP
is
fundamental,
since
it
might
be
misdiagnosed
as
miscarriage
or
simply
intrauterine
pregnancies
[
3
,
4
,
25
].
Such
misdiagnoses
occur
especially
when
women
are
scanned
in
the
late
first
trimester
of
pregnancy,
as
after
7
weeks
the
sac
slowly
“moves”
towards
the
uterine
cavity
and
gradually
changes
shape
and
assumes
an
intra-cavitary
position
that
may
lead
to
its
misdiagnosis
as
an
intrauterine
pregnancy.
Unfortunately
many
overlook
that
the
placenta
stays
anchored
in
the
niche
or
on
the
scar
giving
resulting
in
the
clinical
picture
of
PAS.11].
More
importantly,
recent
evidences
highlight
the
role
of
early
first
trimester
ultrasound
not
only
in
detecting
the
most
severe
complication
arising
from
a
CSP,
the
occurrence
of
PAS,
but
also
in
predicting
the
surgical
outcome
of
these
anomalies
[
22
].
This
growing
body
of
evidence
of
the
role
of
early
first
trimester
assessment
in
predicting
the
presence
and
the
outcome
of
the
Table2
QualityassessmentoftheincludedstudiesaccordingtoNewcastle-OttawaScale
(NOS)astudycanbeawardedamaximumofonestarforeachnumbereditem
withintheSelectionandOutcomecategories.Amaximumoftwostarscanbegiven
forComparability.
Author Year Selection Comparability Outcome
Lopez-Giron[35] 2020 $$ $ $$ Li[36] 2019 $ $ $$ Naeh[37] 2019 $$ $ $$ Orhan[38] 2019 $ $ $$ Tanaka[39] 2019 $$ $ $$ Grechukhina[40] 2018 $$ $ $$ Jachymski[41] 2018 $ $ $ Karahasanoglu[42] 2018 $$ $$ $$ Kim[43] 2018 $$ $ $$ Kim(2)[44] 2018 $$ $ $ Monteagudo[45] 2018 $$ $ $ Sel[46] 2018 $$$ $$ $$ Shafqat[47] 2018 $$ $ $$ Hong[48] 2017 $$ $ $$ Washburn[49] 2017 $$ $ $$ Gao[50] 2016 $ $ $$ Boza[51] 2014ì6 $$ $ $$ Ouyang[52] 2015 $ $ $$ Riaz[53] 2015 $$ $ $$ Rheinboldt[54] 2015 $ $ $$ Wang(2)[55] 2015 $$ $ $$ Yang[56] 2014 $$ $ $$ Zhang[57] 2013 $$ $ $$ Uysal[58] 2013 $$ $ $ Zhang(2)[59] 2013 $$ $$ $$ He[60] 2011 $ $ $$ Sadeghi[61] 2010 $$ $ $ deVaate[62] 2010 $$ $ $ Muraij[63] 2009 $$$ $$ $$ Michener[64] 2009 $$ $ $$ Yan[65] 2007 $$ $ $$ Wang[66] 2006 $ $ $$ Sugawara[67] 2005 $$ $ $$ Maymon[68] 2004 $ $ $$ Seow[69] 2004 $$ $ $$ Seow(2)[70] 2004 $ $ $$ Jurkovic[71] 2003 $$ $ $$ Table3
pooledproportionfortheoutcomesexploredinthepresentsystematicreviewinwomenwithanearly(<9weeks)andinthosewithalate(>9weeks)diagnosisofCSP.
Outcome Studies(n) Pregnancies
(n/N) RawProportions (95%CI) I2 (%) PooledProportions (95%CI)
CSPdiagnosed9weeksofgestation
Compositeadverseoutcome 36 32/724 4.4%(3.1 6.2) 47.7 5.94%(3.5 9.0)
Massivehemorrhage 31 16/581 2.7(1.6 4.5) 31.7 4.32(2.3 7.0)
Needforbloodtransfusion 21 6/445 1.3(0.5 3.1) 0 1.52(0.6 2.8)
Uterinerupture 33 11/537 2.0(1.1 3.7) 6.4 2.46(1.2 4.1)
Emergencyintervention 35 14/523 2.7(1.5 4.6) 0 3.65(2.2 5.4)
CSPdiagnosed>9weeksofgestation
Compositeadverseoutcome 22 19/61 31.1(20.2 44.4) 63.1 32.39(15.7 51.8)
Massivehemorrhage 21 16/59 27.1(16.7 40.5) 49.8 28.00(14.1 44.5)
Needforbloodtransfusion 13 6/41 14.6(6.1 29.9) 28.8 15.82(5.5 30.2)
Uterinerupture 21 1/58 1.7(0.1 10.5) 0 7.52(2.5 14.9)
Emergencyintervention 21 8/55 14.55(6.9 27.2) 45.3 16.33(5.9 30.6)
most
severe
iatrogenic
complications
of
CSP
questions
whether
a
screening
policy
aimed
at
diagnosing
these
anomalies
early
in
pregnancy
should
be
undertaken
in
order
to
improve
maternal
outcome.
In
the
last
decades,
introduction
of
different
screening
policies,
including
those
for
fetal
aneuploidies,
pre-eclampsia
and
preterm
birth,
has
demonstrated
that
early
pregnancy
assessment
may
translate
in
more
accurate
diagnosis
and
improved
maternal
outcomes.
[
75
,
76
]
However,
there
is
a
little
debate
of
whether
we
should
screen
for
CSP
and
PAS
anomalies,
despite
their
signi
ficant
impact
on
women
’s
health,
especially
when
undiagnosed.
The
World
Health
Organization
(WHO)
states
that,
in
order
to
apply
a
screening
program
to
a
speci
fic
population,
several
criteria
should
be
accomplished.
Such
criteria
include,
among
the
others,
the
knowledge
of
the
natural
history
of
the
disease,
the
presence
of
an
accepted
treatment
and
the
availability
of
a
test
with
high
level
of
accuracy
for
the
diagnosis
of
a
given
disorder.
[
77
]
Although
not
all
these
points
can
be
entirely
applicable
to
CSP
and
PAS
disorders,
recent
published
studies
highlight
that:
1
Prenatal
diagnosis
of
CSP
is
easier
in
the
early
compared
to
late
first
trimester
of
pregnancy
[
22
,
25
]
2
Early
diagnosis
would
allow
parents
to
make
a
more
conscious
decision
about
their
pregnancy.
3
Early
identi
fication
of
CSP
and
PAS
would
allow
prompt
referral
to
center
with
high
expertise
in
prenatal
diagnosis
and
surgical
management.
[
13
,
21
]
The
findings
from
this
systematic
showed
that
early
first
trimester
diagnosis
is
associated
with
a
decreased
risk
of
adverse
maternal
outcome,
thus
strengthening
the
authors
beliefs
based
upon
daily
clinical
practice.
In
view
of
all
these
issues,
it
is
collective
authors
’
opinion
that
every
woman
with
a
prior
CD
should
be
offered
an
early
(ideally
at
5 7
weeks
and
before
9
weeks
of
gestation)
first
trimester
transvaginal
ultrasound
assessment
in
order
to
rule
out
CSP.
As
highlighted
above,
the
screening
should
be
performed
in
the
early
first
trimester
and
not
at
the
time
of
the
11
–14
weeks
scan
in
view
of
the
high
rates
of
false
negative
diagnosis
of
CSP
in
this
gestational
age
interval.
[
25
]
Despite
this,
several
potential
limitations
on
the
practical
application
of
such
screening
policy
should
be
acknowledged.
Early
first
trimester detection
of
CSP
might
pose
ethical
issues,
since
it
is
still
challenging
to
differentiate
between
women
affected
by
CSP
who
will
experience
acute
life-threatening
conditions
in
the
first
or
second
trimester,
such
as
uterine
rupture
or
severe
hemorrhage,
and
those
who
will
progress
to
the
third
trimester
developing
PAS
disorders,
which
can
be
amenable
of
treatment.
Therefore,
such
practice
may
lead
to
a
higher
rate
of
unnecessary
termination
of
pregnancy.
More
importantly,
a
screening
policy
for
early
first
trimester
assessment
of
women
with
a
prior
CD
would
require
the
introduction
of
an
additional
scan,
which
would
mean
additional
costs
for
patients
and/or
national
health
systems,
thus
highlighting
the
need
for
a
careful
evaluation
of
its
cost-ef
ficacy.
Of
note,
there
is
still
a
lack
of
consensus
of
how
to
manage
CSP
in
early
gestation
and
the
findings
from
this
systematic
review
are
not
based
on
randomized
trials
comparing
early
versus
late
intervention.
Alongside
these
unsettled
questions,
the
results
from
this
systematic
review
highlight
the
need
for
future,
large
studies
aimed
at
elucidating
the
role
of
early
ultrasound
assessment
in
pregnancies
with
a
prior
CS
and
its
impact
on
women
’s
health.
Conclusions
Early
first
trimester
diagnosis
of
CSP
is
associated
with
a
lower
risk
of
adverse
maternal
outcome.
The
findings
from
this
systematic
review
support
the
clinical
effectiveness
of
a
policy
of
screening
of
all
women
with
a
prior
CD
in
order
to
promptly
detect
and
treat
CSP,
although
the
cost-effectiveness
of
such
policy
should
be
tested
in
future
studies.
Funding
No
speci
fic
funding
was
obtained.
Declaration
of
Competing
Interest
The
authors
declare
that
they
have
no
known
competing
financial
interests
or
personal
relationships
that
could
have
appeared
to
in
fluence
the
work
reported
in
this
paper.
Acknowledgments
None.
Appendix
A.
Supplementary
data
Supplementary
material
related
to
this
article
can
be
found,
in
the
online
version,
at
doi:
https://doi.org/10.1016/j.ejogrb.2020.11.036
.
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