Cervical Cerclage – Professional Recommendations

CLINICAL ACTIONS:

Cervical insufficiency is defined by ACOG as “the inability of the uterine cervix to retain a pregnancy in the absence of signs and symptoms of labor in the second trimester.” In addition, the indication for cerclage is separated out into 3 categories

• History: Suggestive of cervical insufficiency
  • Second trimester pregnancy losses related to painless cervical dilation and no history of labor or abruption
• Physical Examination: Also known as ‘physical examination–indicated cerclage’, ‘rescue cerclage’ and ‘emergency cerclage’
  • Patient presents with painless second trimester cervical dilation
• Ultrasound: Cervical length shortening and history of preterm birth
  • Singleton pregnancy
  • Prior spontaneous preterm birth
  • Cervical length: <25 mm | measured between 16w0d to 24w0d

Timing of Cerclage Placement

• History-indicated cerclage
  • Place between 12w0d and 14w6d after confirmation of pregnancy viability
• Ultrasound-indicated cerclage
  • Place between 16w0d and 24w0d
• Exam-indicated cerclage
  • Place ≤24w0d 0/7
  • Not advised in the setting of intra-amniotic infection or labor

Risk Factors

• Prior PTB
• Cervical procedures (including cone and LEEP)
• Cervical laceration
• Congenital Müllerian anomalies

Note: Risk factors are not an indication for cerclage

Twin Gestation

• Examination-indicated cerclage
  • Recommended for cervical dilation in the second trimester without evidence of intra-amniotic infection or labor
  • Same as singleton gestations
• Ultrasound-indicated cerclage
  • Not recommended for cervical shortening <25 mm in twin gestations
• Prophylactic (“twin-only”) cerclage
  • Not advised in the absence of cervical dilation or shortening

SYNOPSIS:

Clinically, cervical insufficiency is painless dilation and recurrent mid-trimester losses without signs of preterm labor (PTL), PPROM, or infection. Patient history may include superimposed symptoms (i.e. bleeding, pressure), therefore a judicious review of records is advised.  Those with a history of prior preterm birth can benefit from cervical length screening to appropriate guide selected patients for cerclage..

KEY POINTS:

Ultrasound Indicated Cerclage <24 weeks

• With history of preterm birth
  • Decreased preterm birth 
  • Improved neonatal outcomes  
• No history of preterm birth
  • For CL <10 mm without prior PTB, evidence remains insufficient to recommend for or against cerclage 
• Evidence from research studies
  • There is no demonstrated difference in efficacy of McDonald versus Shirodkar techniques

‘Emergency’ Cerclage (Exam indicated)

• Evidence supports ’emergency’ or ‘rescue’ cerclage
• Rule out uterine activity or intraamniotic infection

Alternative Therapies (Singleton Gestations)

• Vaginal progesterone
  • Reasonable alternative to ultrasound-indicated cerclage for singleton pregnancies with prior spontaneous preterm birth and cervical shortening
• Cervical pessary
  • Not recommended as an alternative to cerclage

Transabdominal Cerclage

• Indicated after one history- or ultrasound-indicated transvaginal cerclage resulting in spontaneous birth <28 weeks of gestation
• Minimally invasive approach (laparoscopic or robotic-assisted) preferred over laparotomy when available
• May be placed prepregnancy or in the first trimester (generally 9 to 18 weeks if placed during pregnancy)

Additional Interventions

• Evidence does not support use of the following after cerclage placement
  • Serial cervical length measurements
  • Reinforcing (“second”) cerclage for cervical shortening on follow-up – not shown to improve outcomes and may increase risk of preterm birth
  • Antibiotics (routine use outside of exam-indicated cerclage)
  • Prophylactic tocolysis (routine use outside of exam-indicated cerclage)
• Perioperative indomethacin plus cefazolin may be considered specifically for exam-indicated cerclage – increases likelihood of prolonging pregnancy ≥28 days, though neonatal benefit is not established

Cerclage Removal

• Remove vaginal cerclage at 36w0d to 37w6d
  • Removal up to 39w6d may be considered in select circumstances (e.g., planned delivery) absent an earlier indication for removal
• Cesarean delivery planned for ≥39 weeks
  • May be removed at time of delivery
  • Consider possibility of spontaneous labor between 37 and 39 weeks
• Vaginal cerclage may be removed in the office
• PPROM
  • Removal or retention must balance risks vs benefits (e.g., infection vs prematurity)
  • Prolonged antibiotic prophylaxis >7 days not recommended if suture is retained

Learn More – Primary Sources:

ACOG Practice Guideline 12: Obstetric Cerclage

Physical Examination–Indicated Cerclage: A Systematic Review and Meta-analysis

SMFM Consult Series 65: Transabdominal cerclage – SMFM Publications and Clinical Guidelines