Learning objectives

• Describe the indications and risks for cervical cerclage
• Manage patients presenting for cervical cerclage

Background

• Cervical cerclage is performed as an attempt to prolong pregnancy in women who are at high risk of preterm delivery due to cervical insufficiency
• Suturing of the cervix to prevent rupture of fetal membranes

Risk factors for cervical insufficiency

• Prior cervical procedures or trauma:
  • Loop electrode excisional procedure
  • Cone biopsy
  • Prior cervical lacerations
  • Repetitive cervical dilation and/or pregnancy terminations 
• Maternal connective tissue diseases or abnormalities
• Congenital Mullerian anomalies
• Maternal exposure in utero to diethylstilbestrol

Indications

• History-indicated: One or more second-trimester pregnancy losses related to painless cervical dilation and in the absence of labor or abruptio placentae, or prior cerclage placed due to cervical insufficiency in the second trimester
• Ultrasound-indicated: History of spontaneous loss or preterm birth at less than 34 weeks if the cervical length in a current singleton pregnancy is less than 25 mm before 24 weeks of gestation
• Rescue cerclage: Singleton pregnancy at less than 24 weeks with advanced cervical dilation in the absence of contractions, intraamniotic infection, or placental abruption 
• Not recommended in pregnancies of multiple gestations

Technique

• Transvaginal
  • McDonald method: Simple purse-string suture at the cervicovaginal junction
  • Shirodkar method: Suturing anterior-posterior and posterior-anterior after an incision of the mucosa of the anterior cervix, with the aid of an Allis clamp
• Transabdominal
• Remove sutures between weeks 36-38 in women anticipating vaginal delivery: 
  • McDonald cerclage requires no anesthesia
  • Shirodkar requires anesthesia (spinal, epidural)
  • Highly epithelialized sutures may require Cesarean section

Risks

• Rupture of fetal membranes
• Infection or sepsis
• Lacerations at the surgical site
• Anesthesia-related complications

Management

Suggested reading

• Bieber KB, Olson SM. Cervical Cerclage. [Updated 2022 Aug 1]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK560523/
• Shennan, A, Story, L, Jacobsson, B, Grobman, WA; the FIGO Working Group for Preterm Birth. FIGO good practice recommendations on cervical cerclage for prevention of preterm birth. Int J Gynecol Obstet. 2021; 155: 19– 22.