When should a cervical pessary be placed and where can I buy one, such as an Arabin (cervical pessary) or Donut (cervical pessary)?

Cervical Pessary Placement: Timing and Availability

Based on the most recent 2024 Society for Maternal-Fetal Medicine guidelines, cervical pessary should NOT be routinely placed for prevention of preterm birth in singleton pregnancies with short cervix, as the evidence does not support its use (GRADE 1B recommendation). 1

Current Guideline Recommendations

For Singleton Pregnancies

• The Society for Maternal-Fetal Medicine explicitly recommends AGAINST cervical pessary placement for prevention of preterm birth in individuals with singleton gestation and short cervix 1
• This represents a reversal from earlier practice, as conflicting trial results have failed to demonstrate consistent benefit 1
• Vaginal progesterone is the preferred first-line treatment for singleton pregnancies with cervical length ≤20 mm diagnosed before 24 weeks (GRADE 1A) 1

For Twin/Multiple Gestations

• Routine use of pessary is NOT recommended for twin gestations with cervical shortening outside of clinical trials (GRADE 1B) 1
• Large randomized trials in unselected twin populations showed no benefit 1

When Pessary Placement Was Previously Considered

Historical Timing Parameters (No Longer Recommended)

If pessary were to be placed (which current guidelines advise against), the historical approach was:

• Gestational age window: 18-24 weeks of gestation 1
• Cervical length threshold: ≤25 mm on transvaginal ultrasound 1
• Removal timing: 36-37 weeks of gestation or earlier if complications develop 1

Why Guidelines Changed

The evidence is conflicting and ultimately negative:

• One Spanish trial showed 82% reduction in preterm birth <34 weeks (6% vs 27%) 1
• However, a larger multinational trial of 932 women found NO benefit (12.0% vs 10.8% preterm birth rate) 1
• An Italian trial showed benefit, but 85% of patients also received vaginal progesterone, confounding the results 1

Trade Names and Availability

Arabin Pessary

• The Arabin pessary is NOT FDA-approved for sale in the United States for any indication 1
• It can only be used under an investigational device exemption in the U.S. 1
• This is a silicone ring-shaped pessary specifically designed to encircle the cervix 1

Alternative Pessaries

• Other pessaries (ring devices, Smith-Hodge lever design) are FDA-approved for pelvic organ prolapse and incontinence 1
• Use during pregnancy for preterm birth prevention is OFF-LABEL for all FDA-approved pessaries 1

Where to Obtain

• In the United States: Cannot purchase Arabin pessary commercially; requires investigational device exemption 1
• Outside the United States: May be available through medical device suppliers in countries where approved
• Given current guidelines recommend against use, procurement is not clinically indicated 1

What to Do Instead

Recommended Evidence-Based Approach

1. Screen with transvaginal ultrasound at 18-24 weeks in high-risk patients 1
2. If cervical length ≤20 mm: Prescribe vaginal progesterone 200 mg nightly (GRADE 1A) 1
3. If cervical length 21-25 mm: Consider vaginal progesterone based on shared decision-making (GRADE 1B) 1
4. If cervical length <10 mm: Cerclage can be considered even without cervical dilation, based on shared decision-making 1

Common Pitfalls to Avoid

• Do not place pessary based on older 2017 guidelines—the 2024 SMFM guidelines supersede previous recommendations 1
• Do not use 17-OHPC (hydroxyprogesterone caproate) for short cervix treatment—this is explicitly not recommended (GRADE 1B) 1
• Do not place cerclage routinely for short cervix 10-25 mm without cervical dilation (GRADE 1B) 1

Side Effects (If Pessary Were Used)

Historical data shows:

• 100% of patients report increased vaginal discharge 1
• 11-14% require pessary repositioning 1
• Serious adverse events (cervical ischemia) are rare 1
• No increased infection, premature rupture of membranes, or bleeding 1