Simulation
Materials and Preparation
- Purchase the simulation model
- The full model can be purchased, if desired, but not necessary
- Complete model (limbsandthings.com) with "membranes" ~$1000
- At minimum, you only need the closed cervix model and dilated cervix model
- Closed Cervix (limbsandthings.com) - $125 (Figure 1)
- Dilated Cervix (limbsandthings.com) - $125 (Figure 2)
- Craft based alternatives include:
- Foam cylinders (Amazon) for closed cervix
- Foam pads (Amazon) for closed cervix (can cut cylinders) and for dilated cervix (can cut circles with holes, or role into a dilated cervix)
- Cardboard rolls (Amazon) (can also use old toilet paper rolls, paper towel rolls) for dilated cervix
- The full model can be purchased, if desired, but not necessary
- Plastic liners for hospital water pitchers (Figure 3)
- This serves as a “clear” vagina to insert the cervix model into, and mimics operating in a small space (Figure 4)
- Additionally, the transparency gives faculty easy visualization to supervise surgical technique.
- Ziploc bags with rubber bands, to fill with water to simulate amniotic sac.
- Alternative, clear balloons
- Needle drivers (both straight and Heaney®)
- Ring forceps
- Long pick ups
- Suture scissors
- Kelly® clamps
- Hemostats
- Cook balloon® and/or 30 cc foleys
- Syringes and water to inflate Cook balloon® and/or foleys
- Sutures – recommend V37 needle Ethibond, Mersilene
Set Up
1. Make a quarter size hole in the bottom of the water pitchers using scissors.

2. Place cervix model in the created hole.
3. Pour water into the Ziploc bags and place rubber band around it to create a “sac”. This can be placed inside the dilated cervix model to mimic the amniotic sac.
4. Ensure each station has:
- Sutures
- Ring forceps x 2
- Needle drivers (both straight and Heaney®)
- Long pick ups
- Suture scissors
- Kelly® clamps
- Hemostats
- For the dilated model, a Cook balloon® and/or 30 cc foleys and syringes and water to inflate them
Figures
Figure 1: Closed Cervix Model
Figure 2: Dilated Cervix Model
Figure 3: Plastic liners for hospital water pitchers
Figure 4: Cervix model inside Figure 3
Sequence of Lab/Checklist for Faculty
- Position the cervix-vagina model on any surface that mimics an operating table. Ensure that learner and faculty are on the same side.
- The necessary equipment should be at each station, as described in the “set up” portion of the simulation exercise
- The learner discusses preop management options (depends on cerclage indication and gestational age): doptones, antibiotics, anesthesia, positioning, etc.
- The learner will call for and identify the instruments used in the simulation: sutures, ring forcep, needle driver, long pick ups, suture scissors, Kelly® clamps, Hemostats, Cook balloon® and/or foleys
- The learner describes the method upon he/she/they would start the cerclage placement
- The learner describes key surgical anatomy.
- The learner grasps and positions the cervix, and the learner practices suturing steps of the cerclage on the model, with feedback from the instructor.
- The learner identifies and discusses the proper technique to use to avoid injury to the vagina, cervix, amniotic sac, nearby structures.
- The learner describes securing hemostasis
- The learner discusses post op management for the patient (depends on cerclage indication and gestational age): doptones, antibiotics, pain medications, tocolytics.
- The learner discusses timing of and indications for cerclage removal.
- The learner practices removing the cerclage stitch they placed into the cervical model.
- The learner discusses possible follow up if concern for retained cervical cerclage stitch.
Competency Assessment
The resident should be able to:
- Identify, select, and correctly use the appropriate instruments
- Describe and practice on the model the steps of a cerclage (both dilated and nondilated cervix)
- Discuss timing, indications, management of pre and post-operation of cerclage management for patients
- Complete a cerclage placement and cerclage removal
The CREOG Surgical Skills Task Force created this simulation as part of a standardized surgical skills curriculum for use in training residents in obstetrics and gynecology.