POP-Q Staging and Pessary Selection: A Clinical Reference for OB/GYNs

POP-Q staging gives every clinician the same anatomical language — but the number alone does not tell you which pessary to place. A patient with a stage II cystocele and a 3 cm genital hiatus has a very different fitting trajectory than a patient with the same stage II classification and a 5 cm hiatus. This reference maps all nine POP-Q measurement points, the five ICS/AUGS stages, and the selection variables that actually drive shape choice — compartment, GH, TVL, prior hysterectomy, and patient self-management capacity — into a single clinical decision framework your team can consult at the fitting table.

In this reference:

• POP-Q system: all nine measurement points with clinical interpretation
• Stages 0–4 verbatim from the ICS/AUGS standard
• Why GH >4 cm overrides stage-based selection logic
• Comprehensive algorithm table: stage × compartment × pessary shape
• Fitting decision tree, escalation protocol, and special-scenario reference card
• Quick-reference product and fitting kit links

What Is the POP-Q System? The Nine Measurement Points Explained

The Pelvic Organ Prolapse Quantification (POP-Q) system was developed under joint agreement by the International Continence Society (ICS), the American Urogynecologic Society (AUGS), and the Society of Gynecologic Surgeons (SGS) in 1996. It replaced the Baden-Walker halfway system as the current international standard for prolapse staging. All measurements are taken at maximum Valsalva strain with the patient in lithotomy or standing position; reference plane is the hymen (0 cm). Points above the hymen are negative (normal); points below the hymen are positive (prolapsed). The AUGS interactive POP-Q tool provides a digital reference for clinicians in training or for documentation audit purposes.

Anterior compartment points

• Aa — Anterior wall, fixed point: Midline anterior vaginal wall, 3 cm proximal to the external urethral meatus (i.e., 3 cm above the hymen on the anterior wall). By definition, Aa ranges from −3 to +3 cm. A value of −3 cm is normal; +3 cm indicates full anterior wall descent at this fixed reference point.
• Ba — Anterior wall, most distal point: The most distal (dependent) position of any part of the upper anterior vaginal wall between Aa and the vaginal cuff or anterior fornix. Ba ranges from −3 cm (normal, equal to Aa at −3 when there is no prolapse) to a positive value equal to TVL in complete eversion. Ba is the key severity indicator for anterior wall (cystocele) prolapse.

Apical compartment points

• C — Cervix or vaginal cuff: The most distal edge of the cervix (in a patient with uterus) or the leading edge of the vaginal cuff (post-hysterectomy). Normal value: C is typically more than −TVL/2 above the hymen. C at or beyond the hymen = stage III or IV apical prolapse depending on TVL.
• D — Posterior fornix: The location of the posterior fornix (only recorded in patients with an intact uterus; omitted post-hysterectomy). A significantly more positive D relative to C may suggest uterine elongation rather than true apical descent. D provides context for distinguishing apical from cervical elongation in uterine prolapse.

Posterior compartment points

• Ap — Posterior wall, fixed point: Midline posterior vaginal wall, 3 cm proximal to the hymen. Ranges from −3 to +3 cm, analogous to Aa for the posterior wall.
• Bp — Posterior wall, most distal point: Most distal position of the upper posterior vaginal wall between Ap and the vaginal cuff or posterior fornix. Analogous to Ba for the posterior compartment. Key indicator for rectocele / posterior wall prolapse severity.

Anatomical landmarks (not prolapse measurement points)

• GH — Genital hiatus: Measured from the middle of the external urethral meatus to the posterior midline hymen. Normal range approximately 2–3.5 cm. GH ≥3.75–4 cm is a clinically significant threshold: an enlarged genital hiatus predicts apical support failure and is an independent predictor of support pessary expulsion regardless of POP-Q stage. GH >4 cm is the single most important override variable in pessary selection — see Section 4 below.
• PB — Perineal body: Measured from the posterior midline hymen to the midanal opening. Reflects perineal body integrity. A short PB (<2.5 cm) combined with wide GH indicates significant posterior compartment support loss.
• TVL — Total vaginal length: Maximum vaginal depth with the prolapse fully reduced. Normal range 7–10 cm. TVL <6 cm significantly constrains pessary options — smaller-diameter devices only, and the Cube may be the only space-filling shape that achieves adequate wall contact in very short vaginas.

POP-Q Stages 0–4: Verbatim ICS/AUGS Definitions

The following stage definitions are reproduced from the ICS/AUGS POP-Q standard. Stage is determined by the most advanced portion of the prolapse. All measurements taken at maximum Valsalva. Reference the Physiopedia POP-Q reference and the StatPearls POP overview for additional measurement guidance.

Stage	Definition (ICS/AUGS)	Clinical correlate
Stage 0	No prolapse demonstrated. Points Aa, Ba, Ap, Bp are all at −3 cm; C or D is between −TVL and −(TVL − 2) cm.	Normal pelvic support. All points well above hymen. Incidental finding on pelvic exam in an asymptomatic patient.
Stage I	The most distal portion of the prolapse is more than 1 cm above the level of the hymen (most distal prolapse quantification point is <−1 cm).	Mild support loss, generally asymptomatic. Leading edge does not reach the hymen. Most patients do not report vaginal bulge at this stage.
Stage II	The most distal portion of the prolapse is between 1 cm above and 1 cm below the hymen (−1 cm to +1 cm, inclusive).	Leading edge at or just past the hymen. Patients frequently begin reporting a sensation of vaginal pressure or bulge, particularly with prolonged standing or Valsalva. Symptomatic prolapse typically correlates with stage ≥II (leading edge at or beyond hymen).
Stage III	The most distal portion of the prolapse protrudes more than 1 cm below the hymen but no further than 2 cm less than the total vaginal length [i.e., the quantification value is >+1 cm but <+(TVL − 2) cm].	Leading edge beyond the hymen by >1 cm. Vaginal bulge typically visible, often reducible. Stage III is the most common presentation at initial clinical evaluation for symptomatic POP. Multicompartment involvement common.
Stage IV	Essentially complete eversion of the total length of the lower genital tract is demonstrated. The distal quantification point is at least (TVL − 2) cm.	Near-complete or complete vaginal eversion (procidentia when all compartments involved). Patients typically cannot reduce the prolapse manually at rest. Constant bulge, voiding difficulty, constipation, and mucosal ulceration are common presentations. Fitting is most challenging at this stage.

Takeaway: Stage III and IV prolapse and a genital hiatus >4 cm each, independently, shift pessary selection away from support devices toward space-filling shapes (Gellhorn, Cube, Donut). When both are present simultaneously, a support pessary trial is rarely productive and delays definitive fitting.

The Core Pessary Selection Variables — Beyond Stage Number

POP-Q stage establishes the severity of prolapse but does not, by itself, determine which pessary to use. The following variables must be assessed at every initial fitting encounter. Each one can override or modify what stage-based logic would otherwise suggest.

Genital hiatus (GH) — the most consequential single measurement

GH >4 cm is the primary override signal in the selection algorithm. A support pessary (ring, ring with support, dish) rests against the pubic symphysis anteriorly and the posterior vaginal fornix posteriorly. When the hiatus is wide, there is insufficient introital resistance to retain a support pessary under Valsalva or ambulation — regardless of stage. In clinical practice:

• GH <3.5 cm: Ring or Ring with Support is likely adequate for stage I–II; trial ring before escalating.
• GH 3.5–4.0 cm: Ring with Support as first attempt; anticipate possible expulsion; have Gellhorn ready as next step.
• GH >4.0 cm: Begin directly with space-filling pessary (Gellhorn preferred). Do not waste appointment time on support pessary trials that anatomy predicts will fail.

Total vaginal length (TVL)

• TVL <6 cm: Significantly restricts options. Smaller diameter Gellhorn (2.0–2.25 inch), smaller Cube sizes, or Mar-Land pessary. Ring with Support may be limited in effectiveness. Thoroughly document TVL so subsequent clinicians understand the anatomical constraint.
• TVL 6–8 cm: Standard sizing range for all shapes.
• TVL >8 cm: May require larger pessary sizes or long-stem Gellhorn.

Prior hysterectomy

The cervix provides a natural posterior support for ring-type pessaries seating against the posterior fornix. Post-hysterectomy, that anatomical anchor is absent. Ring pessaries frequently expel in vaginal vault prolapse patients even when GH is not excessively wide. For any patient with prior hysterectomy and symptomatic apical prolapse, initiate with Gellhorn rather than ring. This is a categorical override, not a size adjustment.

Dominant prolapse compartment

• Anterior dominant (cystocele, high Ba): Ring with Support or Dish pessary as first line. Mechanism: support membrane bridges the anterior defect and elevates the bladder base against the pubic symphysis.
• Posterior dominant (rectocele, high Bp): Gehrung pessary (dual anterior–posterior arch support) or Hodge pessary (lever action, mild posterior descent). Standard ring does not adequately address posterior wall prolapse in isolation.
• Apical dominant (high C, vault prolapse, uterine descent): Gellhorn first line; Donut for stage II–III with uterus present and spacious vault; Cube for stage III–IV after Gellhorn and Donut have been tried.
• Multicompartment: Gellhorn handles combined apical + anterior most effectively; Gehrung addresses combined anterior + posterior without significant apical.

Patient self-management capacity

• Ring with Support: self-management teachable at first or second visit; preferred when patient has good dexterity, tolerates vaginal manipulation, and wants independence.
• Gellhorn: most patients require clinician insertion and removal; build scheduled removal visits into the care plan from the outset.
• Cube: retrieval string enables self-removal; nightly removal strongly recommended due to discharge accumulation; assess patient dexterity and willingness before selecting.
• Donut: difficult for most patients to self-manage; requires clinician visits.
• Gehrung / Hodge: can sometimes be managed by patients with instruction, but fitting is technically demanding for the clinician.

Explore the full range of pessary fitting sets at Minerva Health to systematically trial shapes by compartment.

Sexual activity

• Ring with Support: compatible with sexual intercourse in most patients.
• Gellhorn, Donut, Cube: sexual intercourse is not possible with the device in situ; document this in counseling.
• Dish / Gehrung / Hodge: generally compatible but individual anatomy determines comfort.

Concurrent stress urinary incontinence (SUI)

A cystocele mechanically kinks the urethra, masking latent SUI. After pessary fitting corrects the prolapse, occult SUI frequently unmasks. Perform a cough stress test with the pessary in place before the patient leaves the clinic. If SUI is unmasked, consider adding a knob variant or switching to a Ring with Knob pessary or Dish with Knob. This is not a secondary concern — de novo SUI is one of the most common reasons patients discontinue pessary use within the first 3 months.

The Comprehensive Algorithm Table: POP-Q Stage × Compartment × Pessary Shape

The table below maps POP-Q stage against the dominant prolapse compartment to give a structured starting point for pessary selection. Read the table as a starting framework, not a protocol: GH measurement, TVL, prior hysterectomy, and patient variables all modify the selection, as described in sections above and the clinical notes below the table.

POP-Q Stage	Anterior (Cystocele / Ba)	Posterior (Rectocele / Bp)	Apical (Uterine / Vault / C)	Multicompartment / Mixed
Stage 0–I	Ring pessary (no support plate needed). Consider expectant management if asymptomatic.	Ring or Hodge; manage symptomatically. Many stage I posterior presentations are asymptomatic.	Ring pessary; observe for progression. Reassess in 3–6 months if symptomatic.	Ring pessary; watchful waiting acceptable in asymptomatic patients.
Stage II	Ring with Support (first line). Dish as alternative if broader support platform preferred. GH <4 cm required for support pessary retention.	Gehrung (combined A+P support arch) or Hodge (lever, mild posterior + retroverted uterus). Ring with Support if anterior compartment is co-dominant.	Ring with Support. If uterus present and large GH, trial Donut. Post-hysterectomy: proceed directly to Gellhorn.	Ring with Support if GH ≤4 cm. Gehrung if posterior component is significant. Gellhorn if GH >4 cm.
Stage III	Ring with Support if GH ≤4 cm. Gellhorn if GH >4 cm or ring expelled. Gellhorn provides apical anchoring that also reduces anterior wall descent.	Gehrung (first line for posterior dominant). Gellhorn if Gehrung fails or significant apical component present. Donut if uterine prolapse co-exists with wide posterior descent.	Gellhorn (first line). Gellhorn pessary — suction disc + stem; resists expulsion at wide GH. Donut: uterus present + spacious vault + stage II–III. Post-hysterectomy: Gellhorn default.	Gellhorn (manages all three compartments via apical anchoring). If GH >4 cm and stage III: do not trial ring — start with Gellhorn directly.
Stage IV	Gellhorn (first line). Cube if Gellhorn expelled or anatomically not feasible. Active ulceration: local estrogen 4–6 weeks before any fitting attempt.	Gellhorn (apical anchor reduces posterior pressure). Cube if Gellhorn fails. Surgical consultation if no space-filling pessary achieves retention.	Gellhorn (standard or long-stem). Cube if Gellhorn fails. Donut as alternative to Gellhorn when uterus is present and vault is spacious (no hysterectomy). Surgical consultation when all shapes fail.	Gellhorn → Cube escalation path. Manual reduction required before fitting attempt. TVL <6 cm: smaller Gellhorn diameter or Cube only option in some patients.
Post-hysterectomy (any stage)	Ring with Support → Gellhorn (cervical anchor absent; ring expulsion common)	Gehrung → Gellhorn (posterior support without cervical anchor)	Gellhorn (first-line default). Cube if Gellhorn fails. No role for standard Ring — vault prolapse without cervix is a categorical Gellhorn indication.	Gellhorn → Cube. Do not waste fitting session on ring trial in post-hysterectomy vault prolapse.

GH Override Rule — applies at every stage and every compartment: When GH >4 cm is confirmed on examination, escalate directly to a space-filling pessary (Gellhorn preferred) regardless of what the stage column above indicates. This single measurement predicts support pessary failure more reliably than POP-Q stage alone. Do not trial a Ring or Ring with Support when GH >4 cm — it delays fitting and erodes patient confidence in pessary management.

Additional table notes: TVL <6 cm limits to smaller diameter devices — use smaller Gellhorn sizes or Cube. Concurrent SUI: add knob variant (Ring with Knob or Dish with Knob) to selected shape when SUI is the primary concurrent complaint. Posterior-dominant prolapse without significant anterior or apical involvement: Gehrung is the most anatomically targeted option; a standard ring does not adequately address isolated posterior wall prolapse.

Takeaway: POP-Q stage provides the starting framework; GH measurement, TVL, compartment dominance, prior hysterectomy, and patient self-management capacity refine the selection to the specific shape. Of these variables, GH >4 cm is the most actionable single override.

Fitting Decision Tree: Step-by-Step Logic

The following sequence reflects the clinical workflow for pessary fitting in a patient with symptomatic POP. Use this alongside the algorithm table above.

Step 1 — Pre-fitting measurements: Measure and document GH, PB, and TVL. Identify the dominant prolapse compartment by assessing Aa/Ba (anterior), Ap/Bp (posterior), and C/D (apical). Record the POP-Q stage.

Step 2 — TVL screen: Is TVL <6 cm? If yes — inform the clinical decision immediately. Options are limited to smaller-diameter devices. Proceed with smaller Gellhorn sizes (2.0–2.25 inch) or Cube. Skip Ring with Support as a first-line option. If TVL ≥6 cm, proceed to Step 3.

Step 3 — GH override screen: Is GH >4 cm? If yes — initiate with a space-filling pessary (Gellhorn first). Do not trial a support pessary. The anatomy will not retain it. If GH ≤4 cm, proceed to Step 4.

Step 4 — Compartment-based selection: Using GH ≤4 cm as the precondition, apply compartment logic. Anterior dominant → Ring with Support (use the Ring with Support Fitting Set for systematic sizing). Posterior dominant → Gehrung or Hodge. Apical dominant or post-hysterectomy → Gellhorn.

Step 5 — Trial fitting: Insert the selected pessary. Test retention with Valsalva, coughing, and brief ambulation. Confirm approximately 1 cm of circumferential space between the pessary rim and vaginal wall for comfort and mucosal integrity. If retained and comfortable: proceed to Step 6. If expelled: increase size one increment before changing shape. If two size increments fail: change shape (see Escalation Protocol below).

Step 6 — Cough stress test: With the pessary in situ, perform a standing cough stress test. SUI unmasked? If yes: consider adding a Ring with Knob or switching to a Ring with Knob pessary or Dish with Knob variant. Document the finding and the plan.

Step 7 — Schedule follow-up: First follow-up at 1–2 weeks to confirm comfort, retention, voiding, and inspect mucosa. Thereafter: every 3–6 months depending on pessary type and patient self-management ability. Patients who cannot self-remove (most Gellhorn users) require scheduled clinician removal visits — build this into the care plan at the initial encounter.

Escalation Protocol: When the First Shape Fails

A systematic escalation approach reduces unnecessary device costs, minimizes patient discomfort from failed attempts, and documents the clinical rationale for each successive choice. Size before shape: always attempt one to two size increments within the same shape family before switching to a different device.

First choice — outcome	Next step	Clinical rationale
Ring with Support expelled on first sizing	Ring with Support, one size larger	Sizing before shape. Most expulsions at first fitting are a size mismatch, not a shape mismatch.
Ring with Support expelled at maximum appropriate size	Gellhorn pessary — use Gellhorn Fitting Set	Wide hiatus or advanced POP that support pessary mechanism cannot overcome. Space-filling suction mechanism required.
Gellhorn expelled at initial size	Gellhorn, one to two sizes larger; or long-stem Gellhorn	Short stem may not anchor at apical depth; larger diameter or longer stem improves suction seal. Confirm TVL accommodates larger size.
Gellhorn (all sizes) fails to be retained	Cube pessary — use Cube Fitting Set	Six-sided distributed suction addresses anatomical variation that a single-disc device cannot. Last-resort non-surgical option.
Donut uncomfortable or expelled	Gellhorn	Gellhorn stem orientation provides more stable apical anchoring than the toroidal volume-fill mechanism of the Donut in most anatomies.
Cube: discharge unacceptable despite daily cleaning protocol	Document all pessary trials and refer for surgical consultation	Non-surgical fitting options exhausted. Surgical evaluation is the appropriate next step, not additional pessary variants.
Gehrung expelled or poorly tolerated	Gellhorn (if significant apical component); Hodge (if mild posterior + retroversion)	Gehrung fitting is technically demanding; re-verify arch orientation before shape change. If anatomy is not compatible with arch placement, escalate to Gellhorn.

Takeaway: Systematic size escalation within a shape before changing shapes reduces unnecessary device costs and patient discomfort, and produces clearer documentation of the clinical decision pathway.

Special Clinical Scenarios: Reference Card

The following scenarios arise frequently in urogynecology and OB/GYN practice. Use this as a quick-reference card alongside the algorithm table.

• Prior hysterectomy + vaginal vault prolapse (any stage): Gellhorn is the default first-line pessary. Ring expulsion is frequent and predictable without a cervix to anchor the posterior fornix seat. Proceed directly to Gellhorn trial. Cube if Gellhorn fails.
• Uterine prolapse (uterus present) + large GH: Gellhorn or Donut. Donut cervix-rest technique works when vault is spacious; Gellhorn when GH is very wide or Donut does not seat correctly. Both require clinician removal.
• Combined anterior + posterior prolapse without significant apical involvement: Gehrung pessary. Its dual-arch design simultaneously supports the anterior and posterior walls — the only pessary shape designed for this specific anatomy. See the Gehrung pessary page for sizing guidance.
• Combined anterior + apical prolapse after ring failure: Gellhorn. Apical anchoring via disc suction secondarily reduces anterior wall descent — a single device addresses both compartments.
• Concurrent SUI + anterior prolapse: Ring with Knob pessary or Dish with Knob. The knob compresses the urethrovesical junction against the pubic symphysis. Confirm knob position with post-fitting cough stress test.
• Postpartum or perimenopausal patient (observe for spontaneous resolution): Ring pessary with reassessment at 3–6 months. Many postpartum prolapse presentations partially resolve with pelvic floor recovery. Avoid over-escalating shape selection in this population before observing natural progression.
• Atrophic mucosa, high erosion risk (postmenopausal, estrogen deficiency): Prescribe or recommend low-dose vaginal estrogen 4–6 weeks before the fitting appointment. Refit after mucosal conditioning. Pessary contact on thin atrophic epithelium significantly increases ulceration risk and causes avoidable complications.
• Patient who cannot attend regular follow-up (anticipated non-compliance): Ring with Support is preferred over Gellhorn or Cube. If a Gellhorn becomes incarcerated in a patient who has not been seen for 6+ months, removal can require significant clinical intervention. Minimize incarceration risk by using the device most tolerant of extended intervals between clinician visits. Counsel all patients on the mandatory follow-up schedule regardless of device selected.
• Stage IV procidentia (all compartments) in a high-surgical-risk patient: Manually reduce prolapse before any fitting attempt. Begin with Gellhorn. Ensure mucosal ulceration has been treated with estrogen prior to device insertion. Consider temporarily using a donut to reduce the prolapse while estrogen conditions the mucosa, then refit with Gellhorn. Document that surgical management was discussed and declined or deferred.
• Active vaginal ulceration: Absolute contraindication to new pessary fitting. Prescribe local estrogen; refit in 4–6 weeks after mucosal healing confirmed on examination.

Browse the full Prolapse Solutions collection at Minerva Health to view available shapes and fitting kits for each clinical scenario above.

Quick-Reference Product Links for Clinicians

The table below consolidates pessary shapes with their primary POP indications and corresponding Minerva product and fitting kit links. Use this as a chairside ordering reference to minimize time between fitting decision and product procurement.

Shape	Primary indication	Product	Fitting set
Ring / Ring with Support	Stage I–III anterior; mild apical; GH ≤4 cm	Ring Pessary	Ring with Support Fitting Set
Dish / Dish with Knob	Mild–moderate anterior prolapse; concurrent SUI (knob variant)	Dish Pessary	Dish Fitting Set
Gellhorn	Stage III–IV; apical; vault prolapse; GH >4 cm; post-hysterectomy	Gellhorn Pessary	Gellhorn Fitting Set
Cube	Stage III–IV; last resort after Gellhorn and Donut failure	Cube Pessary	Cube Fitting Set
Donut	Stage II–III uterine prolapse; uterus present; spacious vault	Donut Pessary	Order by size directly
Gehrung	Combined anterior + posterior prolapse; stage II–III; no significant apical	Gehrung Pessary	Order by size directly
Hodge	Mild posterior prolapse + uterine retroversion; stage I–II posterior	Hodge Pessary	Order by size directly
Ring with Knob	Concurrent SUI + anterior prolapse (knob compresses urethra against symphysis)	Ring with Knob Pessary	Ring with Knob Fitting Set

For compartment-specific guidance, see the companion cluster posts in this series: pessary selection for cystocele and anterior wall prolapse, pessary selection for rectocele and posterior wall prolapse, pessary options for uterine and apical prolapse, pessary management of stage 3–4 advanced prolapse, and pessary vs. surgery counseling framework. The complete clinical guide to pessaries for pelvic organ prolapse provides pillar-level context for all compartments.

Browse the complete Pessary Fitting Sets collection at Minerva Health for all available trial kits. All Bioteque and Milex pessaries stocked by Minerva are FDA 510(k)-cleared Class II devices per 21 CFR 884. Fitting kits are for clinician use only.

For clinical evidence supporting pessary selection in POP, the Cochrane 2020 systematic review (Bugge et al.) provides the most comprehensive RCT evidence synthesis available. The IUGA expert opinion on vaginal pessaries in POP management offers practical fitting guidance including success rates (70–90% symptom resolution), continuation data, and contraindication criteria.

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Frequently Asked Questions

How does POP-Q staging guide pessary selection?

POP-Q staging identifies the severity of prolapse and provides the starting point for pessary selection. Stage I–II typically indicates a trial of support pessaries (ring, ring with support, dish) for anterior and mild apical prolapse. Stage III–IV typically requires space-filling pessaries (Gellhorn, Cube, Donut). However, stage number is always interpreted alongside GH, TVL, dominant compartment, prior hysterectomy, and patient self-management capacity. A stage II patient with GH >4 cm will fail a support pessary trial and should start with a Gellhorn.

What POP-Q stage indicates a Gellhorn pessary is needed?

Gellhorn is first-line for most stage III–IV presentations, for any stage with GH >4 cm, for post-hysterectomy vaginal vault prolapse at any stage, and whenever a Ring with Support has failed despite correct sizing. GH >4 cm is a categorical Gellhorn indication regardless of stage — this override applies even in stage I or II patients if their hiatus measurement crosses this threshold.

What is the clinical difference between POP-Q stage 2 and stage 3?

Stage II: the leading edge of prolapse is between 1 cm above and 1 cm below the hymen (−1 cm to +1 cm). Patients often begin experiencing symptoms at this stage. Stage III: the leading edge is more than 1 cm below the hymen but not greater than TVL − 2 cm. The prolapse is visibly outside the introitus, typically causing a constant vaginal bulge and frequently requiring manual reduction or change in position to void or defecate. The shift from stage II to stage III often marks the transition from support pessary candidacy to space-filling pessary preference, particularly when GH is wide.

When does a wide genital hiatus override the POP-Q stage in pessary selection?

GH >4 cm overrides stage-based selection at any POP-Q stage. A support pessary mechanism depends on introital resistance to maintain position against Valsalva. When the hiatus is wider than 4 cm, that resistance is insufficient regardless of prolapse severity, and the pessary will expel. In practice, proceed directly to Gellhorn when GH >4 cm is measured — this single variable is more predictive of support pessary failure than stage, compartment, or TVL alone.

What pessary is appropriate for post-hysterectomy vaginal vault prolapse?

Gellhorn is the default first-line pessary for vaginal vault prolapse after hysterectomy. The absence of the cervix eliminates the anatomical anchor that ring-type pessaries use to seat against the posterior fornix. Ring expulsion in post-hysterectomy vault prolapse is predictable regardless of size selection. If the Gellhorn fails at all appropriate sizes, transition to the Cube as the next space-filling option. The Gellhorn Fitting Set enables systematic size trials in a single fitting session.

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