THE PERINATAL OUTCOME IN SAUDI WOMEN WITH EMERGENCY
CERCLAGE – A PROSPECTIVE STUDY
Taher Al Jishi, MD
Department of Obstetrics, Gynecology And Newborn Care,
University of Ottawa
ABSTRACT
Objective: To evaluate perinatal outcome after placement of
emergency cerclage, in Saudi women who present with a
dilated cervix and bulging or ’hour-glass’ membranes in the
absence of labor. To compare the perinatal outcome in Saudi
women with emergency cerclage with the results published in
the peer reviewed international literature.
Methods: Prospective data collection on perinatal and
maternal outcomes of Saudi women who had an emergency
cerclage placed by operators at the Riyadh Central
Maternity Hospital in the Kingdom of Saudi Arabia from
April 2005 to October 2005. For comparison of the local
outcome with the published experience, a literature review
was conducted with the terms ‘cerclage’, ‘cervix’,
’emergency or emergent cerclage’, ’rescue cerclage’ and
‘incompetent cervix’, using an OVID interface to access
MEDLINE records. The mean values and standard deviations or
range were calculated for the following outcomes of
interest: gestational age and cervical dilatation at the
time of emergency cerclage, gestational age at delivery,
latency of pregnancy from cerclage placement to delivery,
birth weight of the infant. Adverse maternal and perinatal
outcomes were tabulated.
Results: In the specified time frame, 14 women underwent
emergency cervical cerclage at the Riyadh Central Maternity
Hospital. The average time between cerclage placement and
delivery was 7 weeks and 3 days, which allowed for 12 of 14
neonates to be born at 28 weeks or later. 3 neonates had a
birth weight under 1000 g. The average neonatal survival
was 93%. Histological data are available for 12 placentas.
2 placentas demonstrated a histological diagnosis of
chorioamnionitis, although none of the blood cultures from
the neonates revealed septicemia. The PPROM rate was 14%.
The literature review from 1993 to 2005 identified 24 peerreviewed publications, which described the perinatal
outcome of 638 women who underwent emergency cerclage for
the same indications as the present cohort study of Saudi
women.
The average prolongation of the pregnancy was 7 weeks and 1
day. The average neonatal survival exceeded 70% (range
47.2% to 96%) and 60% of the neonates (range 26% to 80%)
were born after 28 weeks gestation. Chorioamnionitis was
reported in 5% to 80% of pregnancies and preterm premature
rupture of the membranes complicated an average of 29% of
gestations (range 1% to 58%).
Conclusion: The results of this prospective study as well
as the data available in the medical literature suggest
that emergency cerclage can significantly prolong pregnancy
and increase the likelihood of fetal viability. These
therapeutic benefits have to be considered in light of the
increased risk of chorioamnionitis and associated fetal
inflammatory brain insult as well as the risk of extending
pregnancy from previability to severe prematurity.
INTRODUCTION
Prematurity is the single largest factor in neonatal
mortality and is responsible for half of all neonatal death
(1). Furthermore, preterm birth generates a significant
financial burden for the health care system and the society
at large, because of the need for intensive neonatal care
for several weeks as well as the continuing, often
lifelong, support necessary after discharge from hospital.
Cervical incompetence represents a component of the
heterogenous etiology of prematurity. In current practice,
cervical incompetence is associated with a history of
passive, painless dilatation of the cervix, which
ultimately results in midtrimester pregnancy loss or
premature delivery.
The etiology of cervical incompetence is unknown in most
instances. Traumatic cervical injury, congenital
abnormalities, and inadequate collagen or elastin have been
suggested as possible causes (2,3).
Women with poor pregnancy outcome attributed to cervical
incompetence are identified clinically based on the finding
of a partly dilated cervix in the absence of labor or by
transvaginal sonographic measurement of cervical length.
There is controversy whether cervical incompetence is an
all-or-none phenomenon. When cervical length, assessed
sonographically, is correlated with duration of gestation,
cervical competence proves to be a spectrum of performance
rather than a dichotomy and the term cervical incompetence
becomes a misnomer (4).
The placement of a prophylactic cerclage, based on either a
history of poor cervical performance in a previous
pregnancy or decreased cervical length identified by
transvaginal ultrasound, has not been supported by results
from randomized trials (1, 5). However if the pregnant
woman presents with premature dilatation of the cervix and
bulging or ‘hour-glassing’ membranes in the absence of
uterine activity, an emergency or rescue cerclage may be
indicated. There is debate about the efficacy of this
intervention in terms of pregnancy prolongation and longterm outcomes related to severe prematurity.
The goal of this study was to review the experience with
rescue cerclage in a large maternity hospital in Saudi
Arabia and to compare the perinatal outcome in the Saudi
population with the published experience in the medical
literature. The present study, as well as the review, focus
exclusively on emergency cervical cerclage placed in
patients with either bulging or hour-glassing membranes in
the absence of labor.
METHODS
The study was conducted at the Riyadh Maternity Hospital,
a tertiary care facility with an average of 10,000
deliveries annually.
Data Collection:
Following departmental approval, a database was set up in
April 2005 to collect prospectively information on all
women with singleton pregnancies, who underwent emergency
cerclage over a six months period. The database included
antenatal and obstetrical history and perinatal/neonatal
outcomes.
Inclusion Criteria:
The diagnosis of incompetent cervix relied on clinical
criteria: finding of a dilated cervix and/or bulging or
hour-glassing membranes in the absence of labor. The
decision to place a rescue cerclage, the selection of the
cerclage technique, the method for replacing the bulging
membranes, the decision to confine the women to bed rest in
hospital after cerclage placement, the use of antibiotics
and tocolytics, were left to the discretion of the
obstetricians, who were unaware of the ongoing prospective
data collection project. The author of this study was not
involved in the care of patients with rescue cerclage, his
role was limited to accurate data collection.
Data Interpretation & Analysis:
The efficacy of the rescue cerclage was determined by
examining the following outcomes: latency interval from
cerclage placement to delivery, gestational age (GA) at
delivery, adverse neonatal outcomes related to prematurity,
and maternal procedure related complications.
Data analysis was accomplished with the Sigmastat 2.0
statistical software program (SYSTAT Software Inc., Point
Richmond, California).
Mean values and the corresponding range or standard
deviations were calculated for the following variables: GA
at placement of the emergency cerclage, dilatation of the
cervix, GA at delivery, latency of pregnancy from cerclage
to delivery and birth weight (BW) of the neonates.
Significant adverse perinatal/neonatal and maternal events
were recorded as secondary outcomes: perinatal mortality,
respiratory distress syndrome (RDS), chronic lung disease,
necrotizing enterocolitis (NEC), retinopathy of
prematurity, neurologic complications of prematurity and
sepsis. Chorioamnionitis was considered when clinically
suggestive findings were supported by the histologic
diagnosis of the placenta. Neurologic complications of
prematurity were defined as severe intraventricular
hemorrhage (IVH) (grade III or IV)(6), cystic
periventricular leukomalacia (7), blindness and deafness.
Brain ultrasonographic or magnetic resonance imaging (MRI)
was performed when it was considered clinically indicated
by the treating neonatologist. Brain ultrasonography was
routinely performed twice in the first two weeks of life
for all neonates delivered prior to 32 weeks gestation and
MRI whenever the clinical examination, ultrasonography or
both were suggestive of an abnormality. Newborns free of
any of the above complications at 6 months of age were
reported to be ‘alive without major neurological
morbidity’.
Comparing the results with the published literature:
In order to compare the local experience with the published
medical literature, an electronic MEDLINE search, without
language restrictions, was performed, using the following
key words and medical subject heading (MESH) terms:
’cerclage’, ‘cervix’, ‘emergent or emergency cerclage’,
‘rescue cerclage’ and ‘incompetent cervix’. The articles
retrieved were cross-referenced in order to enhance the
thoroughness of the search. Articles, using ultrasound to
diagnose cervical incompetence or shortening, were excluded
because the available evidence does not support cerclage
for a sonographically shortened cervix (8, 9). The
literature search was limited to the period between January
1, 1993 and December 31, 2005, because a preceding
exhaustive review on cervical cerclage, related to articles
published from 1980 to 1992 inclusive (10). After
completing the literature search, each article was screened
and the eligibility for inclusion in the review was
determined.
Data Abstraction:
Data were abstracted using a standard collection form
developed at the beginning of this project. Key
characteristics of the studies, antenatal and obstetrical
history, perinatal/neonatal and maternal outcomes were
abstracted. As it is controversial to perform a
standardized quality evaluation on observational studies
(11), the quality of the studies included in the literature
review was described using the US Preventive Services Task
Force guidelines (12).
RESULTS
Between April 1, 2005 and October 1, 2005, 6087 patients
were delivered at the Riyadh Maternity Hospital. During the
same period fourteen (0.22%) pregnant women with singleton
pregnancies, underwent an emergency cerclage. All relevant
antenatal, obstetrical and pregnancy outcome data for these
14 patients are presented in Table 2. The average GA at the
time of cerclage placement was 23 weeks plus 2 days and the
average latency to delivery was 7 weeks and 4 days.
11 of 14 neonates (78%) were born at 28 weeks gestation or
later. A histologic diagnosis was available for 10
placentas. Two of 4 cases of clinical chorioamnionits
failed to be confirmed histologically. One stillborn
neonate was delivered 5 days after cerclage placement and
the remaining 13 neonates were born alive. The birth weight
was under 1000 grams in 2 newborns born at 27 weeks
gestation. The 11 remaining live born neonates weighed over
1000 grams at birth (average weight x grams, range 1090 to
2780 grams). 10 of the 13 surviving infants (77%) were
admitted to NICU and had an average duration of stay of 32
days. Three infants born after 36 weeks’ gestation were
discharged home with their mother one day after delivery.
Two neonates developed RDS and one neonate had IVH grade
III, PVL and retinopathy of prematurity, but no cases of
NEC or sepsis were noted. Twelve infants were reported at
six months as ‘alive without major neurological morbidity’.
The McDonald cerclage technique was employed in all
patients. None of the patients had preoperative
amniocentesis for amnioreduction or to rule out
chorioamnionitis. Preterm premature rupture of the
membranes (PPROM) complicated the pregnancies of two woman
and occurred at 7 and 14 days after placement of the
cervical cerclage.
Prior to cerclage placement, a soaked sponge stick was used
in four women to replace the amniotic membranes, which were
protruding into the vagina. A 24 hours course of
antibiotics but no tocolytics were used in all women. Nine
pregnant women (64%), who underwent cerclage placement,
were confined to bed rest as inpatients for up to 8 weeks
and four women had lifestyle changes, with reduced
physicial activity, implemented as outpatients. Ten women
received a course of antenatal corticosteroids for
enhancement of fetal lung maturity when delivery appeared
imminent.
The literature search from 1993 to 2005, identified 72
publications reviewing institutional or individual
experience with cervical cerclage. In studies reviewing the
experience with all types of cerclage (prophylactic and
emergent), only data pertaining to emergency cerclage were
abstracted. 48 publications were found unsuitable for the
review because they were pertaining only to prophylactic
cerclage. 24 studies (10, 13-35) with a total of 638
pregnant women undergoing emergency cerclage, were included
in the literature review. With the exception of one
randomized controlled study (34) and one prospective case
series (35), the selected publications include mostly
retrospective case reviews. These studies reflect obstetric
practice from North America (13, 16, 21, 35), Latin America
(29, 33), Europe (10, 19 22, 27, 28), the Middle East (18,
30) and the Far East (17, 20, 23, 24). The abstracted data
from the 24 studies are summarized in Tables 3 and 4.
The average gestational age at cerclage was 22 weeks plus 5
days with an average prolongation of pregnancy of 7 weeks
plus 1 day. This resulted in 60% of neonates being born
after 28 weeks’ gestation, a mean gestational age at
delivery of 29 weeks and 6 days and an average neonatal
survival of over 70%. PPROM complicated 29% of pregnancies,
and chorioamnionitis was reported in 14% to 80% of
pregnancies.
DISCUSSION
This is the first prospective study in the Kingdom of Saudi
Arabia which reviews a single institution experience with
rescue cerclage. The earlier publication of a clinical
epidemiologic review about emergency cerclage in the Assir
region of Saudi Arabia, fails to provide data on perinatal
outcomes, which are the focus of the present case series
(30).
The current understanding of the efficacy and complications
of rescue cerclage is based mostly on retrospective case
series or studies of small sample size, from countries that
may have dissimilar obstetric practice patterns.
The present prospective study and the examination of the
literature generated four important findings.
First and foremost, emergency cerclage can significantly
prolong pregnancy and increase the chance for a good
neonatal outcome in women presenting with cervical
dilatation and bulging or hour-glassing membranes. One
recent randomized controlled trial of emergency cerclage
versus bed rest for a small number of women (N=23) supports
the published observational data and the findings of the
present study from Saudi Arabia (34). The mean latency from
randomization to delivery in the cerclage group was 7 weeks
plus 5 days with a mean gestational age at delivery of 30
weeks, which was significantly different from the bed rest
group (mean latency 2 weeks and 6 days and mean GA at
delivery 26 weeks).
Notwithstanding the beneficial effect of pregnancy
prolongation for the majority of women with emergency
cerclage, the inherent risks of extending the pregnancy
from previability to severe prematurity have to be
considered when counseling patients about emergency
cerclage. Forty percent of pregnant women in the literature
review and 22% in the present study delivered prior to 28
weeks’ gestation, when prematurity has the most serious
consequences.
The second finding of the study and the literature review
is an increase in the incidence of PPROM associated with
emergency cerclage placement. In the present prospective
study from Saudi Arabia, PPROM complicated 14% of
pregnancies, which is lower than the average incidence in
all reviewed studies (29%) and significantly lower than the
52% incidence reported in the largest case series (31). The
reason for the increased association of PPROM with
emergency cerclage placement is unknown but may be related
to a local inflammatory response to the cerclage material
itself or to subclinical chorioamnionitis (35). The lower
incidence of sexually transmitted disease in the more
conservative Saudi society could explain the decreased
frequency of PPROM in the present study (44, 45).
The third finding is that of an increased frequency of
histological chorioamnionits associated with rescue
cerclage. Chorioamnionitis has potential long-term sequelae
for the newborn: cerebral palsy (36, 37) and neurological
morbidity (38) due to inflammatory fetal brain injury and
bronchopulmonary dysplasia (39).
The fourth finding of the review study is that several
outcome variables and the frequency of complications
associated with emergency cerclage differed significantly
between countries and with the size of the study cohort.
Within the same time frame, the mean latency period from
cerclage placement to delivery was reported as 7 weeks
(35), 8 weeks and 4 days (31) and 4 weeks (26) respectively
in studies from Canada (35), Sweden (31) and Italy (26).
This could be due to differing population characteristics
and obstetric practices in various countries and settings.
The present literature review relies on publications in 4
different languages in order to ensure completeness of
information retrieval and to avoid publication bias. No
difference in the quality of studies published in English
versus other languages has been demonstrated (40). It has
been shown that authors are more likely to report in an
international English-language journal if results are
positive, whereas negative findings are more often
published in local journals (41, 42).
The fact that a single author abstracted the key
characteristics of the studies and the perinatal/neonatal
outcomes should not be considered detrimental, as it has
been shown that multiple abstractors do not improve the
quality of a review (43).
There are several inherent weaknesses of the prospective
study and of the literature review.
First, the limited size of the study cohort did not allow
for the performance of subanalysis of different outcome
variables.
The second shortcoming is the limited neonatal follow-up
period. As rescue cerclage often prolongs the pregnancy
from previability to borderline survival and given the
possibility of long-term adverse outcome related to severe
prematurity, the 6 months infant follow-up is inadequate
(35).
A summary article is as good as the published reports it
relies on for data. Of the 24 studies that met the
inclusion criteria for the review, there was only one small
randomized trial (34) and a single prospective study (35).
A shortcoming of this review is that data were derived from
reports that encompassed obstetric practices in 9 different
countries over a span of 12 years.
Difficulties in reviewing the studies included the absence
of standardized terminology for emergency cerclage, the use
of various cerclage techniques (McDonald, Shirodkar, or
Wurm), the variable performance of amnioreduction, the
different methods used to replace the protruding amniotic
membranes (urinary bladder filling, inflated Foley catheter
bulb, soaked sponge stick), the varying use of antibiotics,
tocolytics and mandatory postoperative bed rest.
Although the McDonald technique was most frequently
employed for rescue cerclage placement (16, 17, 18, 19, 24,
25, 34, 35), in several studies the techniques described by
Shirodakar or Wurm (10, 13, 22, 31) were used. However,
there are no data to show the superiority of one of these
three technique. Amnioreduction was inconsistently
performed in several studies (13,28,35) to allow for
greater ease in reduction of the amniotic membranes and to
rule out subclinical chorioamnionitis. In the absence of
sound data to support the use of amnioreduction, clinical
judgement should apply.
The use of broad spectrum antibiotics and/or tocolytics and
the practice of mandating bed rest after cerclage placement
are further examples where the review offers insufficient
data to clarify the management. In addition, it is
uncertain what should be done in case of PROM with a rescue
cerclage in place. Some authors (10, 13, 35) suggest that
the cerclage should be left in place if rupture of the
amniotic membranes occurs at a gestational age when fetal
survival is low. Cerclage removal should be considered when
signs of infection or concerns regarding fetal well-being
develop. A similar approach was used in the management of
two patients who developed this complication during the
present prospective study. Others (31, 32, 33) have
justified the approach of immediate cerclage removal, by
the fact that maternal and fetal risks associated with
chorioamnionitis may outweigh any benefit gained from
further prolongation of pregnancy. The previously
documented differences have contributed to clinical
heterogeneity, which might have prevented the current
review from identifying clinically important benefits of
certain interventions. However, heterogeneity may actually
be viewed as the strength rather than a weakness of this
report. Indeed, rescue cerclage is employed only rarely and
the rate of associated complications is dependent on the
country from which the report originated, the sample size
and the year of publication. Ideally, there would be large
studies from a variety of practice and venue situations
from which clinicians could choose to cite for their own
unique practice environments and populations.
Because cervical rescue cerclage is not commonly employed,
it is unlikely that there will be high quality
investigations that are available for each imaginable
clinical situation. Thus, clinicians have to accept
recommendations that are derived from less than ideal
reviews, such as the present one.
The last weakness is that, by limiting studies to those
published after 1992, potentially useful information may
have been eliminated. The intent was, however, the analysis
to reflect recent practice patterns in obstetrics.
The present prospective study and the literature review
point to two areas of needed future research.
Given the wealth of case series and retrospective data, the
question is no longer whether an emergency cerclage should
be placed but, rather, what the optimal circumstances
surrounding its placement should be.
Although maternal and neonatal complications associated
with rescue cerclage are well known, further studies that
address methods to prevent or decrease morbidities are
needed.