Download الشريحة 1

• Condition in which the cervix fails
to retain the conceptus during
pregnancy.
• There are arguments about the
occurrence and incidence of
incompetent cervix
Affects around
1% of pregnant
patients
Cervical incompetence has
long been recognized as a
potential cause of preterm
delivery & recurrent mid
trimister abortionns.
It is believed that cervical
incompetence is the
cause of 20 - 25 % of all
second trimester losses
1. Idiopathic (most cases).
2. Congenital disorders (congenital mullerian duct
abnormalities eg. Septate uterus, Bicornuate uterus).
3. DES exposure in utero.
4. Connective tissue disorder (Ehlers- Danlos
syndrome).
5. Surgical trauma :
 Conization,( resulting in substantial loss of connective tissue) or
 Traumatic damage to the structural integrity of the cervix :
(repeated forced cervical dilatation associated with D&C).
The cervical competence is an active, not
passive, phenomenon, and it is a
specific entity involving not just an
abnormality or defect of cervical
collagen, but is also due to either:
1. Absence of the usual cervical musculature in
cases of congenital cervical incompetence, or
2. Injury or damage to the cervical musculature
caused by previous trauma.
Women with incompetent cervix
typically present with "silent"
cervical dilatation (i.e., with
minimal uterine contractions)
between 16 and 28 weeks of
gestation.
• Patient present with significant
cervical dilatation (2 cm or more)
and minimal symptoms.
• When the cervix reaches 4 cm or
more, active uterine contractions
or rupture of membranes may
occur.
• The function of the cervix during
pregnancy depends on the regulations
of connective tissue metabolism.
• Collagen is the principal component in
the cervical matrix, others are:
(proteoaminoglycans, elastin and
glycoproteins, like fibronectin).
The biochemical events implicated
in the cervical ripening are:
1. Decrease in total collagen content,
2. Increase in collagen solubility and
3. Increase in collagenolytic activity.
• It is a clinical diagnosis marked by gradual, painless
dilatation and effacement of the cervix with
membranes visible through the cervix.
• This history establishes the diagnosis, eventually,
women with this cervical status may develop
membrane rupture & labor.
• Short labors with the delivery of an immature fetus
or loss of the pregnancy at progressively earlier
gestational ages in successive pregnancies is
characteristic of reduced competence.
– Historical factors
1.History of painless cervical dilatation with preterm
delivery
2.History of forceful cervical dilatation and evacuation
3.History of obstetric trauma: cervical lacerations,
prolonged second stage followed by cesarean
4.Prior cervical surgery: cone, loop
5.DES exposure in utero
– Cervical sonography
6.Short cervical length
7.Cervical funneling
• The diagnosis is at present largely subjective and
retrospective.
• If possible, an objective (i.e. measurable)
diagnosis, made before pregnancy or in the early
stages (first or early second trimester) would
provide :
1. An accurate incidence of cervical incompetence,
2. Allow treatment to be targeted appropriately and
3. Also provide the basis for definitive trials of
treatment.
• Dilators or balloons to determine cervical
resistance and/or hysterosalpingograms to
measure the width of the cervical canal
between pregnancies are neither sensitive nor
specific.
• Digital examination of the cervix is highly
subjective.
• Sonography has provided a reproducible
method of evaluating the cervix.
• Initial use of ultrasound to observe the cervix
was transabdominal but the necessity for a full
bladder to visualize the cervix elongates the
cervix to such a degree as to make objective,
reproducible measurements difficult.
• The development of transvaginal scanning
(TVS) allowed for accurate cervical
measurements with an empty bladder and no
distortion .
'funneling' or 'breaking' of the
internal cervical os
( at rest or particularly in response
to transabdominal pressure on the
uterine fundus )
is the ultrasonographic appearance
of cervical incompetence .
Cervical measurements
• Provide a significant advance in the
diagnosis of cervical incompetence
• In contrast to the hysteroscopic
evaluation of the cervix, it is :
non-invasive, repeatable over time and
can be performed during pregnancy.
1. Funneling of the cervix with the changes
in forms T, Y, V, U (correlation between
the length of the cervix and the changes
in the cervical internal os). (Trust Your
Vaginal Ultrasound)
2. Cervix length < 25 mm
3. Protrusion of the membranes.
4. Presence of fetal parts in the cervix or
vagina
2 images of the same cervix, 20 seconds
apart, without and with applying pressure:
Sonographic serial evaluation
( every two weeks) of the cervix for
funneling and shortening in
response to transfundal pressure
has been found to be useful in the
evaluation of incompetent cervix.
Am J Obstet Gynecol 1997;177:660-5.
• Surgical repair of the cervix using a
vaginal or abdominal approach.
• Other alternatives that have been
considered have included :
1. Bed rest, for which no trial has been
conducted and for which little evidence
of effectiveness exists, and
2. The use of vaginal pessaries to elevate
and close the cervix.
The initial descriptions of cervical
cerclage for cervical
incompetence came with
Shirodkar and McDonald in the
1950s, when both developed
techniques for physical support for
what was presumed to be a
structurally weak cervix.
Cerclage is not
indicated solely based
on risk factors or prior
cerclage placed for
doubtful indications.
Am J Obstet Gynecol 1982 Mar 1;142(5):506-12 ,Obstet Gynecol
1989 Feb;73(2),Am J Obstet Gynecol 1993 Nov;169(5):11259 PMID: 8238171,J Reprod Med 1994 Nov;39(11):880-2 PMID:
Cerclage
Prophylactic
Emergency
• Prophylactic cerclage sutures (Shirodkar, McDonald
)may be placed at 12 to 16 weeks' gestation.
• Do not use tocolytics at the time of prophylactic
cerclage, but give perioperative antibiotics.
• Intercourse, prolonged standing (>90 minutes), and
heavy lifting are omitted following cerclage.
• Follow these patients with periodic vaginal
sonography to assess stitch location and funneling.
• No additional restrictions are recommended as
long as the stitches remain within the middle
or upper third of the cervix without the
development of a funnel, and the length of the
cervix is greater than 25 mm.
• For patients who have not been successful
with a vaginal suture despite aggressive care
and sonographic surveillance, a
transabdominal cerclage may be appropriate.
• Care of the patient with newly detected reduced
cervical competence in the second trimester is
both difficult and controversial.
• When the diagnosis is made before cervical
dilatation has occurred and when there is still
10 to 15 mm or more of cervical length, admit
the patient for 24 hours of treatment with
perioperative indomethacin and broad-spectrum
antibiotics before placing the cerclage sutures,
and observe the patient for 48 to 96 hours
postoperatively.
• However, if the cervix has dilated to allow
visualization of the membranes, the patient
may remain hospitalized for several days after
cerclage placement.
• The prognosis for these patients is better than
generally expected, with many women
delivering a "viable" (usually defined as >1,000
g) infant, but aggressive therapy may be
required to achieve these results.
• The prognosis is influenced by the gestational
age at the time when the suture is placed.
In the case of advanced dilatation with bulging
membranes, several techniques may be helpful:
1. Pre cerclage amniocentesis to remove sufficient fluid to
reduce the bulging membranes can be helpful.
2. Overfilling the bladder with 1,000 ml of saline may help by
elevating the membranes out of the operative field, but may
also obstruct the surgeon's view.
3. Place a Foley catheter balloon inside the cervix, and overfill it
with at least 50 ml of saline to gently push the membranes
out of the lower segment.
The cerclage suture can then be placed and tied as the
balloon fluid is evacuated.
• Cerclage is rarely performed after 24 to 25
weeks of pregnancy.
• The great risk of inducing PROM or
preterm labor and the ability to prolong
gestation with bed rest and suppressive
medications argue against surgical
intervention in such cases.
• The cerclage is removed at 37 weeks'
gestation or at the onset of labor.
1. History compatible with incompetent
cervix AND
2. Sonogram demonstrating funneling OR
3. Clinical evidence of extensive obstetric
trauma to cervix
ACOG Criteria Number 17 October 1996, ACOG
Criteria Number 18 October 1996
1.Uterine contractions.
2.Uterine bleeding
3.Chorioamnionitis
4.Premature rupture of membranes
5.Fetal anomaly incompatible with
life
There are five different techniques for performing the
cerclage:
1. McDonald procedure
2. Shirodkar operation
3. Wurm procedure (Hefner cerclage)
4. Transabdominal cerclage
5. Lash procedure
The two most common are the McDonald and
Shirodkar.
• The McDonald procedure is done with a 5 mm
band of permanent suture is placed high on the
cervix.
• This is indicated when there is significant
effacement of the lower portion of the cervix.
• It is generally removed at 37 weeks, unless
there is a reason to remove it earlier, like
infection, preterm labor, premature rupture of
the membranes, etc.
• It is also shown that this has very little impact of
the chance for vaginal delivery.
• The McDonald technique requires
no bladder dissection, and the
cervix is closed using four or five
bites with the needle to create a
purse string around the cervix.
• The Shirodkar is also a frequently used
technique.
• However, this was previously a permanent
purse string suture that would remain intact for
life.
• There are physicians performing modified
techniques, where the delivery does not
necessarily have to be by cesarean, nor the
suture left intact.
• Place the suture as near the internal os as,
opening the anterior fornix and dissecting
away the adjacent bladder, before placing the
suture submucosally, tied anteriorly and the
knot buried by suturing the anterior fornix
mucosal opening.
• The original intention with the Shirodkar
method was to leave the suture in place and
aim for delivery by caesarean section.
• Both initially started suturing with catgut,
but Shirodkar turned to fascia lata and
McDonald turned to ( 0 )silk as they
realized the importance of a permanent
cervical support.
• One significant difference since then has
been the present day use of Mersilene
tape as the suture material.
• Both the McDonald and Shirodkar
cervical sutures are equally effective
as a vaginal approach to cervical
cerclage.
• McDonald suture is generally easier to
perform with no major difference in
success.
• The Hefner cerclage, also known as
the Wurm procedure, is used for later
diagnosis of the incompetent cervix.
• It is usually done with a U or mattress
suture, and is of benefit when there is
minimal amounts of cervix left.
One further development in the 1960s was
the description of the transabdominal
cerclage by Benson and Durfee in 1965 a
technique now largely used after the
failure of vaginal cerclage procedures or
in the presence of congenital anomalies,
particularly those produced by
diethylstilboestrol exposure.
The original intention with the
transabdominal approach was that the
suture was inserted between pregnancies
or in early pregnancy, and left in situ for
the rest of the woman's reproductive life,
delivery being undertaken by caesarean
section for each pregnancy.
• In this method, a midline or Pfannenstiel abdominal
incision allows access to the vesicouterine fold of
peritoneum, which is divided and the bladder
reflected caudally.
• The uterine vessels are then identified and a
Mersilene tape suture is passed through the broad
ligament below the uterine vessels in the potential
'free space' between the uterine vessels and the
ureter, with the suture tied anteriorly or posteriorly
(anterior being reported as surgically easier) and
the bladder replaced.
• The last procedure, the Lash, is
performed in the non-pregnant
state.
• It is typically done after cervical
trauma that has caused an
anatomical defect.
• Lash described techniques aimed at
the repair of a specific anterior cervical
structural defect.
The cervical mucosa was opened
anteriorly, the bladder reflected and the
cervical defect repaired with interrupted
transverse sutures before closing the
vaginal mucosa.
1. Ultrasound for anomaly and viability
2. MS-AFP( Alpha Fetopritein) if
appropriate
3. Wet mount.( For vaginal infections).
4. G Beta Streptococci, Gonococci, and
Chlamydia cultures.
Treat appropriately for infection.
•
•
•
•
•
•
Admit for cerclage
NPO after midnight
Bed rest.
Trendelenberg if cervix is effaced or dilated.
Surgical consent
A 100-mg dose of indomethacin may be given
per rectum during the operative period,
followed by a 50-mg oral dose every 6 hours
• McDonald cerclage
• Postop. ,Transfer to postpartum for
observation
• Regular diet
• Bed rest 12-24 hours
• May discharge if no uterine contractions,
vaginal bleeding, or rupture of
membranes during observation.
1. Premature rupture of membranes (1-9%)
2. Chorioamnionitis (Infection of the amniotic sac, 1-7%) (This risk
increases as the pregnancy progresses and is at 30% for a
cervix that is dilated more than 3 cms.)
3. Preterm Labor
4. Cervical laceration or amputation (This can be at the procedure
or at the delivery, from scar tissue that forms on the cervix.)
5. Bladder Injury (rare)
6. Maternal hemorrhage
7. Cervical dystocia
8. Uterine rupture
• For elective cerclage at the beginning of
the second trimester, the risk of infection is
small, estimated at less than 1 percent.
• Later in the pregnancy, displacement of the
suture also can occur (3 to 12 percent).
• A second cerclage has a much lower
success rate.
• Late complications of cerclage
include PROM or preterm labor
and chorioamnionitis.
• When fluid leakage occurs in a
patient with a cerclage, removal of
the suture, to reduce the risk of
infection is controversial.
• Finally, even though cerclage placement is
considered a benign procedure, a maternal
death secondary to sepsis in a patient with
retained cerclage has been reported.
• The liberal use of this surgical procedure
should be carefully balanced against potential
harm, in particular for patients in whom the
indications for cerclage are not clear.
• Cerclage seems to be a very
effective treatment for
incompetent cervix.
• The success rates can be very
high (80-90%), particularly when
done earlier in a pregnancy.
• Cervical incompetence is often over-diagnosed as a
cause of mid-trimester miscarriage.
• Cervical cerclage should only be considered when
the history of miscarriage is preceded by
spontaneous rupture of membranes or painless
cervical dilatation.
• The MAC/RCOG trial of the use of cervical cerclage
reported a small decrease in preterm birth, but no
significant improvement in fetal survival.
(Grade B recommendation)
• Transabdominal cerclage performed
preconceptually has been advocated as a
treatment for second trimester miscarriage
and the prevention of early preterm
labour.
• The reported improvement in pregnancy
outcome is difficult to assess in the
absence of a control group.