Ring Pessary Size 4 (2.75 inches / 70 mm): The Most Commonly Fitted Size

Ring pessary size 4 measures 2.75 inches (70 mm) in outer diameter and is the most commonly fitted size for adult patients with pelvic organ prolapse. Around 40% of first fittings land on size 4. This guide covers who size 4 fits, when to size up or down, the with-support vs without-support choice, and where to buy.

Why providers reach for size 4 first

Size 4 sits in the middle of the standard adult range (sizes 0 through 13). For a woman of average build with one or two vaginal births and mild-to-moderate prolapse, size 4 is the statistical sweet spot. Clinic protocols typically start here, then size up or down based on the fit.

Every SciMed ring pessary is molded from medical-grade silicone in San Jose, California. Size 4 is identical in design to every other size — only the outer diameter changes.

  • Outer diameter: 2.75 inches / 70 mm
  • Material: 100% medical-grade silicone (FDA Class II)
  • Variants: with support (silicone diaphragm) or without support (open ring)
  • SciMed direct price: $49.99 (with support), $44.99 (without support)
  • HCPCS code: A4561 (HSA/FSA eligible)

Who size 4 typically fits

You are a strong candidate for size 4 if most of the following apply:

  • 1 to 2 vaginal births
  • Average adult body frame
  • POP-Q Stage 1 to Stage 2 prolapse
  • No prior pelvic surgery that narrowed the vaginal canal
  • A provider noted normal vaginal length and a relaxed but intact pelvic floor

If you have not been fitted in clinic, the 3-Size Home Fitting Pack bundles sizes 3, 4, and 5 so you can test the most likely starting size and the two adjacent sizes in one purchase.

Size 3 vs Size 4 vs Size 5: comparison table

Size Diameter (inches) Diameter (mm) Typical patient Frequency of use
Size 3 2.50" 64 mm 0-1 births, smaller frame, mild prolapse ~20%
Size 4 2.75" 70 mm 1-2 births, average frame, mild-moderate prolapse ~40%
Size 5 3.00" 76 mm 2+ births, post-menopausal, moderate prolapse ~20%

When to size up to 5

Size 4 is too small if you experience any of these:

  • The ring falls out when you bear down, cough, or have a bowel movement
  • You can feel the ring shift toward the introitus during walking
  • Bulge or pressure symptoms remain after 48 hours of wear
  • The ring rotates 360 degrees with almost no resistance
  • You had 3+ vaginal births and your provider noted a wider pelvic floor

The next step is size 5 (3.00" / 76 mm). If you bought the fitting pack, you already have it on hand.

When to size down to 3

Size 4 is too large if any of these occur:

  • Vaginal pain or pressure that does not resolve in 24 hours
  • Trouble starting or finishing urination
  • Constipation or difficulty passing stool
  • Spotting or visible tissue indentation at the next removal
  • Real difficulty folding the ring to insert it

Drop to size 3 (2.50" / 64 mm). This is most common for petite patients or anyone who had a colporrhaphy or other surgery that narrowed the canal.

Have a question right now?

Message Bharat and the SciMed team on WhatsApp at +1-669-265-9353. Sizing questions answered same-day, no appointment.

With support or without support: choosing the right size 4 variant

Both variants are 2.75" outer diameter. The only difference is the silicone membrane stretched across the center.

Size 4 with support

The Ring With Support includes a perforated diaphragm. Choose this version if you have:

  • Cystocele (bladder / front-wall prolapse) — the most common indication
  • Stage 1-2 uterine prolapse combined with a cystocele
  • Stress urinary incontinence linked to prolapse

Size 4 without support

The open ring (no membrane) is appropriate when you have:

  • Isolated uterine prolapse with no bladder involvement
  • Mild rectocele (read the rectocele guide)
  • A preference for easier folding and removal

When in doubt, the with-support version is the more versatile first purchase — it handles more prolapse patterns.

How to confirm size 4 is your fit

A 48-hour at-home protocol that mirrors what providers do in clinic:

  1. Stand and walk 10 minutes. You should not feel the pessary.
  2. Cough three times forcefully. No downward shift.
  3. Use the toilet. Urination and bowel movement feel normal.
  4. Wear it overnight. No discomfort, no spotting.
  5. Remove and inspect. Tissue looks healthy, no deep ring marks.

If any check fails, swap to the next size up or down using your fitting pack, or order a single replacement.

Insertion and care basics for size 4

The technique is the same for every ring size:

  • Wash hands. Apply water-based lubricant to the ring's rim.
  • Fold the ring in half (it forms a U-shape) and insert with the curve pointing toward the lower back.
  • Push past the pubic bone until the ring snaps open above the pelvic floor.
  • To remove: hook one finger under the rim and walk it down while bearing down gently.
  • Clean with mild soap and water once a week. Air dry. Replace every 6 to 12 months.

For a step-by-step diagram, see the SciMed size and fitting guide.

Where to buy ring pessary size 4

SciMed Store ships pessaries direct from our San Jose, California facility. Direct-to-patient pricing avoids the distributor markup you would see at most clinic offices.

All pessaries are HSA/FSA eligible under HCPCS code A4561.

Frequently asked questions

How do I know size 4 will fit before I order?

Statistically, around 40% of first-time fittings land on size 4, so it is the safest single-size starting point. If you want to remove guesswork, order the 3-size fitting pack and keep the one that fits.

Is size 4 the same across brands?

Yes. Ring pessary sizes are standardized: size 4 is always 2.75 inches (70 mm) outer diameter. Material thickness varies slightly between manufacturers.

Can I wear a size 4 ring pessary during exercise?

Most patients exercise normally with the ring in. If you do high-impact activity (running, jumping) and feel the ring shift, you may need a slightly larger size or a different style.

What if size 4 fits but I still have some pressure?

Wait 7 days. New pessaries often need a short tissue-acclimation period. If pressure persists, size down to 3 or talk to your provider about a different shape (e.g. Gellhorn for more advanced prolapse).

How often do I replace a size 4 pessary?

Every 6 to 12 months for silicone. Replace earlier if you see discoloration, stiffness, or surface pitting.

Is size 4 covered by insurance or HSA/FSA?

Pessaries fall under HCPCS code A4561 and are HSA/FSA eligible. Most plans cover pessaries with a provider note. Ask SciMed for an itemized receipt at checkout.

Order or get help

Questions before you order? WhatsApp Bharat at +1-669-265-9353 or email sales@scimedstore.com. Free sizing guide on request. Made in California. Ships in one business day.

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