Cervical Cerclage (Cervical Stitch) - Complete Procedure Guide

Indications

Contraindications

• Non-viable pregnancy
• Undiagnosed vaginal bleeding
• Ruptured membranes
• Active preterm labor
• Acute cervical or intrauterine infection

• Known or suspected abnormal (chromosomally abnormal) pregnancy
• Prolapsed fetal membranes through the external os (higher risk of iatrogenic membrane rupture)
• Placenta previa with cervical dilation (controversial)

Equipment

• Bladder catheter
• Weighted vaginal speculum
• Deaver or right-angle retractor
• Ring forceps
• No. 5 Mersilene band (nonabsorbable suture) with curved needle - do not confuse with 5-0 suture, which is much smaller
• Pickups (Russian forceps)
• Metzenbaum scissors
• Needle driver

Pre-Procedure Work-Up

1. Confirm intrauterine viability by ultrasound
2. Rule out cervical infection (screen for gonorrhea/chlamydia)
3. Consider amniocentesis for ultrasound-indicated or exam-indicated cerclage (to rule out subclinical chorioamnionitis)
4. Fetal monitoring pre- and post-procedure
5. Obtain informed consent

Step-by-Step Procedure (McDonald Technique)

1. Obtain informed consent and document intrauterine viability.
2. Anesthesia: General or regional (spinal). Local/paracervical block is avoided due to concerns about uterine blood flow alteration.
3. Position the patient in dorsal lithotomy; prep and drape in sterile fashion.
4. Drain the bladder (Foley catheter not required - one-time drain is sufficient).
5. Place a weighted speculum in the posterior vagina.
6. Place a Deaver or right-angle retractor anteriorly for bladder protection; hold carefully to avoid bladder trauma.
7. Grasp the anterior lip of the cervix with ring forceps and displace it superiorly to expose the posterior cervix.
8. Begin the stitch at 6 o'clock (posterior position) in the mid-portion of the cervix, equidistant between the ectocervix and the cervicovaginal junction - i.e., at the level of the internal os. Pass the needle through the mid-cervical stroma - not too shallow (will tear out when tightened) and not through the canal.
9. Proceed counterclockwise (right-handed surgeons): pass the suture to 3 o'clock, exit, immediately re-enter the cervix in the same area, pass to 12 o'clock, exit, re-enter, pass to 9 o'clock, exit, re-enter, finally exit at 6 o'clock.
10. Cinch down the suture like a purse-string - do not draw too tightly - and tie, leaving the ends long enough to grasp with ring forceps for later removal (typically 3 knots).
11. A second cerclage lower than the first is sometimes placed but has no documented improvement in outcome and increases risk of membrane rupture and bladder perforation.
12. Transfer to recovery on a fetal monitor to confirm fetal viability post-procedure.
13. Discharge after adequate observation. Routine antibiotics and tocolytics are NOT routinely recommended.

Common Error: Placing the suture too shallowly so that it pulls through the tissue when cinched tight. Always pass the needle through the mid-cervical stroma.

Post-Procedure Care

• Acetaminophen is usually adequate for pain
• Expect significant vaginal discharge for several weeks
• Pelvic rest: limit physical activity for at least 1 week; abstain from vaginal intercourse for at least 1 week (often for the remainder of pregnancy)
• Increased frequency of prenatal visits
• Bed rest is NOT routinely recommended

Removal

1. Place in examination position, insert speculum
2. Grasp the knot with Russian pickups
3. Elevate and cut the suture with Metzenbaum scissors
4. Remove the stitch

Risks and Complications

Evidence Summary

• Overall cerclage reduces risk of early and late preterm birth (average RR = 0.77; 95% CI 0.66-0.89) per Cochrane review
• Benefit of HIC is primarily seen in women with 3 or more second-trimester losses; evidence is weaker for those with fewer prior losses
• Transabdominal cerclage is superior to transvaginal in patients with prior failed HIC (RCT evidence)
• No evidence supports cerclage in multiple gestations for primary preterm birth prevention
• 2025 meta-analysis (PMID 40829743, Berghella et al.): cerclage for short cervix ≤20 mm before 24 weeks in singleton gestations without prior spontaneous PTB decreases preterm birth

• Pfenninger and Fowler's Procedures for Primary Care, 3rd Ed., pp. 932-933
• Creasy & Resnik's Maternal-Fetal Medicine: Principles and Practice, pp. 889-891
• Berghella V et al., Am J Obstet Gynecol MFM, 2025 [PMID 40829743]
• Mudrik A et al., Am J Obstet Gynecol MFM, 2025 [PMID 40541862] - guidelines on cerclage placement