In The Name Of God

Laleh Eslamian MD Prof of Obstetrics & Gynecology Perinatologist, TUMS CERCLAGE Laleh Eslamian MD Prof of Obstetrics & Gynecology Perinatologist, TUMS

Cerclage is performed to reduce pregnancy loss/preterm birth in women with cervical insufficiency. Cervical insufficiency based on multiple prior 2nd trimester losses and/or preterm births are potential candidates for a ‘history-indicated’ cerclage: best placed at 12 to 14 w. Singleton pregnancy and a short cervical length (eg, <25 mm) on TVS exam at 16 to 23 w are potential candidates for an ‘ultrasound-indicated’ cerclage. Cervical insufficiency based on a dilated cervix on a digital or speculum examination at 16 to 23 w are potential candidates for a ‘physical exam-indicated’ cerclage.

The Role of US in women with Hx of CI Most patients at risk of CI can be safely monitored with TVS in the 2nd trimester. Unnecessary cerclage can be avoided> 50% of cases. Duration of surveillance should begin @16w & ends @ 24w.

Normal cervix

Short cervix

Cervical incompetence

WHO ARE CANDIDATES FOR CERCLAGE ? -Women with Hx of early PTB & TVS evidence of CL shortening <24w, CL < 15 mm : recommend cerclage. -Dilated cervix with visible membranes <24w. -Classic Hx of mid pregnancy birth without other causes.

WHEN WE SHOULD AVOID CERCLAGE? -Short cervix on TVS with out Hx of PTB, marker of PTB but not a specific marker of CI ( Progestrone Tx is recommended unless progressive shortening occurs). Prior PTB when CL remains >10th centile (25mm) in current pregnancy. Twin pregnancy & short cervix (no prior PTB).

Major contraindications to cerclage Fetal anomaly incompatible with life Intrauterine infection Active bleeding Active preterm labor PPROM Fetal demise The presence of fetal membranes prolapsing through the external cervical os: a relative contraindication, because the risk of iatrogenic ROM may exceed 50%. Placenta previa on ultrasound is not an absolute contraindication to cerclage placement.

When Cerclage should be performed? No consensus about the lower and upper limits of GA to perform. In general not performed< 12 weeks of gestation : 1)most miscarriages due to aneuploidy occur in the early and mid-first trimester. 2)waiting permits US evaluation for fetal anomalies and screening and diagnosis of trisomy 21. A cerclage is generally not placed in the 3rd trimester because a delivery ≥ 28 week is likely to have a reasonably good outcome. Cerclage placement at 24 to 28 w, a period characterized by high neonatal morbidity and mortality, is controversial. (individualized)

Preoperative assessment Fetal evaluation: FHR+, GA, R/O aneuploidy & abnormality. Screening for infection: when high risk for STD, amniocentesis? Excluding membrane rupture and preterm labor. Antibiotic prophylaxis: not recommended, ACOG. Perioperative tocolytic drugs: Indomethacin 48h for physical-exam indicated cerclage @ 2nd trimester. Progesterone: continue if previously started.

Preoperative assessment (continued) Anesthesia: regional preferred but both acceptable. Patient preparation: emptying bladder, vaginal prep? Replacement of prolapsedmembranes:Foley,amnioreduction. Surgical goals : 1)The object of cerclage placement is to reinforce the cervix at the level of the internal os; lengthening the cervix is a secondary effect. 2)Upper cervical length ≥10 mm after cerclage & 3)Cerclage height >2 cm: reduced PTD.

McDonald versus Shirodkar procedure The Shirodkar cerclage is placed as close as possible to the level of the internal os after surgically reflecting the bladder anteriorly and the rectum posteriorly. The McDonald cerclage is a purse-string suture that does not involve any dissection (thus, theoretically, it cannot be placed as close to the internal cervical os as the Shirodkar). No significant differences in pregnancy outcome between the two procedures. Higher birth weight when Shirodkar rather than McDonald cerclage was performed for the 2nd procedure (3020 and 2470 g).

Shirodkar Procedure

Shirodkar Procedure

Shirodkar Procedure

Mc Donald Procedure

Mc Donald Procedure

Abdominal Cerclage When trans vaginal approach has failed or anatomical limitations exists: Late 1st trimester Early 2nd trimester( 10-14w) Non pregnant state Much greater risk of hemorrhage( can be life threatening)

Abdominal Cerclage

Number of cerclages One cerclage is usually adequate, if placed well. In some cases, an inadequate initial cerclage is used for traction, and then a 2nd cerclage is placed in a more optimal position closer to the internal os. A 2nd cerclage may be needed to achieve adequate closure of the cervix when the procedure is performed on a widely dilated cervix with prolapsed membranes.   Although some clinicians routinely place a 2nd cerclage, this practice did not improve outcome.

POSTOPERATIVE CARE AND FOLLOW-UP Cerclage is an outpatient surgery procedure. Discharge after being able to ambulate & void. A longer period of in-hospital observation may be indicated for some women who undergo physical exam-indicated cerclage because of their increased risk of complications. **Fetal viability and AF volume should be documented prior to discharge in these cases. Acetaminophen alone provides adequate analgesia for most women. Patients are told to report any leakage of fluid and expect some spotting, cramps, and dysuria (due to minor muscle injury from the vaginal wall retractors) which will abate within a few days. Women who have undergone cerclage placement have an increased frequency of uterine contractions, but the presence of uterine irritability is not predictive of an increased risk of preterm birth.

POSTOPERATIVE FOLLOW-UP Pelvic rest for at least one week after an elective procedure, and to use condoms thereafter. Women who have had a non-history-indicated cerclage: limit physical activity and coitus until a favorable GA usually 32 to 34w. (although there is no high quality evidence that decreasing physical activity improves outcome.) Weekly or biweekly visits for cervical checks to identify patients at highest risk for preterm birth.( ACOG, no) Cervical shortening >23 weeks may prompt administration of antenatal corticosteroids for fetal lung maturation and magnesium sulfate for cerebral palsy prophylaxis.

Cerclage removal The cerclage is removed electively @ 37 w. If a CS delivery is planned: not< 39w. Upon onset of progressive premature labor( clinical judgement). A McDonald cerclage usually can be cut and removed in the office without analgesia. A Shirodkar cerclage often requires a return to the operating room for removal. Patients are generally sent home after cerclage removal to await the onset of labor, which generally occurs within two weeks; only about 10% of women deliver spontaneously within 48 hours of elective cerclage removal. A Shirodkar cerclage does not have to be removed if: 1) Cesarean delivery is anticipated or 2) Future pregnancies are planned.

CERCLAGE & PROM Cerclage should be left in place : 1- in absence of infection 2- <32 w ** prolonged antibiotic Tx > 7d is not recommended **

COMPLICATIONS Uncommon,< 6%. Higher with increasing GA & cervical dilatation. ROM: 2% vs 65% with advanced cervical dilation and/or prolapsed fetal membranes. Intra amniotic infection: 2% vs 25%, severe maternal sepsis. Suture migration: 3-13%, often late in gestation. Cervical dystocia & cervical trauma in labor <5%.

PREGNANCY OUTCOME Viable birth rate of 70 to 90% after history-indicated cerclage, as compared with 10 to 30% prior to the procedure, is subject to bias. The timing of cerclage also affects outcome, emergency cerclage has the worst outcome. An emergency procedure may convert a previable birth to a VLBW premature birth (24 to 27 w) with the potential for serious long-term neurodevelopmental disability.

Vaginal Pessary for CI Smith- Hodge pessary: To alter the axis of the cervical canal & displace the weight of the uterine contents away from the cervix. By changing the angle of the cervix in relation to the uterus, also obstructs the internal os and thus may provide protection against ascending infection. In 2012, a multicenter trial randomly assigned 385 pregnant women with cervical length ≤25 mm at 20 to 23w to use of a cervical pessary or expectant management. 89% had no Hx of previous PTB and none were treated with progestogens or cerclage. Significant in spontaneous preterm <28 w 2 vs 8%, OR: 0.23 <34 w 6 vs 27%, OR: 0.18 Arabin pessary

Thank You

HOW SHOULD WE MEASURE CERVICAL LENGTH? CL CUT OFF? The most reproducible technique for CL assessment is TVS. No management should be done on TAS results.

CL CUTOFF Risk of PTB is inversely related to CL. The risk increases exponentially when CL <15mm. CL <15mm  in 1% of pregnant women including 30% of PTB <34w . CL <25mm  cut off for exponential risk for PTB in multiple pregnancies.