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Patient handout

Cervical Insufficiency (Painless 2nd-Trimester Cervical Dilation)

PRODUCTION

1. Your condition

This handout is for cervical insufficiency (painless 2nd-trimester cervical dilation). Your care team identified this based on: ≥ 1 prior 2nd-trimester pregnancy loss attributable to painless cervical dilation with no other identifiable cause (acog pb 234 history-indicated cerclage substrate).

Other reasons your team may use this plan: tvus cervical length < 25 mm before 24 wk in singleton with prior spontaneous preterm birth (us-indicated cerclage substrate per berghella 2011 pmid 21446209; owen 2009 pmid 19788970); tvus cervical length < 25 mm at 18-24 wk in asymptomatic singleton without prior preterm birth — vaginal progesterone indication per hassan 2011 pmid 21472815; romero 2017 pmid 29630885; painless cervical dilation ≥ 1-2 cm + visible / bulging amniotic membranes on speculum or digital exam at 16+0 to 23+6 wk without contractions or infection (rescue cerclage substrate per cipract althuisius 2003 pmid 14586323; acog pb 234).

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

MedicationStarting doseHowWhenWhat it does
McDonald cerclage (transvaginal purse-string)McDonald purse-string suture at cervico-vaginal junction; placed at 12-14 wk under regional or general anesthesia; outpatient procedure with overnight observation typicaltransvaginal_surgicalsingle placement; remove at 36-37 wk antepartumACOG PB 234 + Cochrane 2017 (Alfirevic PMID 28586127) — elective cerclage reduces recurrent 2nd-trimester loss in history-indicated patients; McDonald is most commonly used; Shirodkar (submucosal) is technically more demanding but comparable outcomes
Shirodkar cerclage (transvaginal submucosal)Shirodkar suture placed submucosally at cervico-vaginal junction; technically more demanding; outcomes comparable to McDonald per modern RCT datatransvaginal_surgicalsingle placement; remove at 36-37 wkComparable outcomes to McDonald per Cochrane 2017; reserved for selected anatomic cases

Plan: Cervical insufficiency management — cerclage (history-, US-, exam-indicated) + vaginal progesterone (asymptomatic short cervix no prior PTB) + pessary alternative (ACOG PB 234 + PB 130 + Berghella 2011 + Owen 2009 + Hassan 2011 + Romero 2017 + Roman 2020 + CIPRACT 2003)

3. When to call your provider

Contact your care team if any of the following happen:

  • New contractions / cramping / decreased fetal movement → return to L&D / ED
  • Painless cervical dilation on routine speculum exam at 16-24 wk → urgent OB consult for rescue cerclage decision
  • TVUS CL < 25 mm with prior PTB → cerclage decision per Berghella 2011
  • New mental health crisis (PHQ-9 ≥ 15 or PCL-5 with suicidal ideation) → urgent mental health referral

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

  • Prior spontaneous preterm birth + current singleton pregnancy + TVUS cervical length < 25 mm before 24 wk → cerclage placement between 16+0 and 23+6 wk (Berghella Obstet Gynecol 2011 PMID 21446209; Owen Am J Obstet Gynecol 2009 PMID 19788970). Reduces preterm birth before 35 wk (RR 0.70), previable birth, and perinatal mortality + composite morbidity. Pre-procedural infection screen + treat. Post-procedural observation 24-48 h. Serial TVUS surveillance q1-2 wk.
  • Cervical dilation ≥ 1-2 cm + visible / bulging amniotic membranes 16+0 to 23+6 wk WITHOUT contractions, infection, or bleeding → emergent rescue cerclage with pre-procedural antibiotics + indomethacin tocolysis (if < 32 wk) per CIPRACT Althuisius 2003 PMID 14586323 + ACOG PB 234. Efficacy controversial; observational + case-series data suggest GA prolongation 4-6 wk. Informed consent essential.
  • Cerclage in situ + complication emergence: (a) regular contractions / PTL refractory to tocolysis → emergent cerclage REMOVAL to avoid cervical laceration; (b) maternal fever + Higgins 2016 criteria → CHORIO → MANDATORY cerclage removal + ampicillin + gentamicin empirics + expedite delivery; (c) PPROM at < 37 wk → case-by-case removal usually within 24-48 h given ascending infection risk; (d) significant vaginal bleeding → case-by-case observation vs removal depending on abruption ddx. Routes to ob.preterm-labor.v1 or ob.chorioamnionitis.v1 or ob.placental-abruption.v1 with cerclage carryover state.
  • Recurrent 2nd-trimester loss after prior transvaginal cerclage → workup uterine anomaly (3D US / saline-infusion sonohysterogram) + connective-tissue (Ehlers-Danlos) + autoimmune; consider transabdominal cerclage (laparoscopic or laparotomy) pre-conception or first-trimester placement in next pregnancy. Transabdominal cerclage mandates cesarean delivery and is left in situ for future pregnancies.
  • PPROM at < 37 wk in patient with cerclage in situ → case-by-case decision regarding cerclage removal — usually within 24-48 h of PPROM diagnosis given high ascending infection risk (cerclage = foreign body). Concurrent corticosteroids (24+0 - 33+6 wk + delivery anticipated < 7 d) + latency antibiotics (ampicillin 2 g IV q6h × 48 h then amoxicillin 250 mg PO q8h × 5 d + erythromycin 250 mg IV q6h × 48 h then 333 mg PO q8h × 5 d per NICHD-MFMU 1997) + magnesium neuroprotection if < 32 wk per ob.preterm-labor.v1 PPROM branch. Close chorio surveillance.

5. Follow-up

6-week postpartum visit + CI-specific anticipatory guidance: recurrence ~ 15-30 % in subsequent pregnancy; preconception MFM consult for next pregnancy planning (cerclage indication review; uterine-anomaly workup with 3D US / saline-infusion sonohysterogram if recurrent loss despite cerclage; connective-tissue / autoimmune review). Mental health screen (EPDS for postpartum depression; PCL-5 for peripartum PTSD especially after mid-trimester loss or extreme preterm). Contraception counseling + interpregnancy interval ≥ 18 mo. Immunization audit (Tdap, flu, COVID per ACIP). Newborn outpatient peds follow-up if delivery occurred preterm.

6. Sources

Guideline: ACOG Practice Bulletin 234 (2014, reaffirmed 2021) Cerclage for the Management of Cervical Insufficiency + ACOG PB 130 (2012, reaffirmed) Prediction and Prevention of Preterm Birth + SMFM Consult Series #20 (2020) Cervical Insufficiency + Berghella Obstet Gynecol 2011 (PMID 21446209) IPD meta-analysis cerclage for short cervix singleton + Owen Am J Obstet Gynecol 2009 (PMID 19788970) NICHD MFMU RCT cerclage in prior PTB + short cervix + Hassan Ultrasound Obstet Gynecol 2011 (PMID 21472815) vaginal progesterone short cervix + Romero AJOG 2018 (PMID 29630885) vaginal progesterone IPD meta-analysis + Roman Am J Obstet Gynecol 2020 (PMID 32592693) twin rescue cerclage RCT + CIPRACT Althuisius 2003 (PMID 14586323) cerclage RCT + Goya PECEP 2012 (PMID 22475493) cervical pessary RCT + Alfirevic Cochrane 2017 (PMID 28586127) cerclage Cochrane meta-analysis

  1. pubmed.ncbi.nlm.nih.gov/21446209
  2. pubmed.ncbi.nlm.nih.gov/19788970
  3. pubmed.ncbi.nlm.nih.gov/21472815