Menstrual Cup Shapes: Finding the Right Fit for Your Body

Menstrual cups may all perform the same basic job, but they do not all look or feel the same. Some are long and narrow, some are short and round, while others have curved sides, angled rims or collapsible bodies.

These differences can influence where a cup sits, how easily it opens, how much pressure you feel and how easy it is to reach for removal. However, cup length, diameter, firmness, capacity, stem design and your cervix height all matter equally when finding a comfortable fit.

Research comparing menstrual cups has found considerable variation between products, with no consistent relationship between a cup's labelled size, shape, capacity or firmness. This means that labels such as small, large or even bell-shaped do not tell you everything you need to know. Checking the cup's actual measurements and features is much more useful.

When should I consider a menstrual cup's shape?

Menstrual cup shape may be a useful starting point if you:

• Know whether your cervix is low, average or high
• Have previously found a cup too long, too wide or difficult to reach
• Experience bladder or vaginal pressure from some cups
• Need more capacity without adding too much length
• Prefer a particular removal aid, such as a stem, loop or ladder
• Want a compact cup for travel

There is no universally best menstrual cup shape. The best option is one that fits your anatomy, opens reliably, stays comfortable and is easy for you to remove.

Are menstrual cup shape categories standardised?

No. Terms such as narrow, bell-shaped, round, U-shaped and V-shaped are useful descriptions, but they are not regulated or consistently defined across brands.

Some cups also overlap categories. A cup described by one manufacturer as bell-shaped may look V-shaped to another person. A U-shaped cup may also be described as rounded or bulbous.

A laboratory comparison of 14 menstrual cups found substantial differences in dimensions, capacity and firmness, even among cups marketed towards similar users. The researchers found no reliable correlation between shape and capacity or between material, shape and firmness. This is why cup measurements and product specifications are more useful than shape alone.

How menstrual cup shape can affect fit

Once inserted, a menstrual cup unfolds inside the vaginal canal and collects menstrual flow beneath the cervix. The rim and body need enough space to open, while the cup must be short enough to remain fully inside the vagina without the base or stem causing irritation.

Shape can affect:

• Where the cup's widest point sits: Some cups are widest near the rim, while others become wider through the body or towards the base.
• How much space the cup occupies: A narrow cup may feel less bulky, while a rounded cup may provide more capacity in a shorter body.
• How the cup opens: Rim design, body firmness and shape can all affect how readily a cup unfolds.
• Where pressure is felt: A wide or firm rim may feel different from a cup with a softer body or more tapered base.
• Removal: The base shape, grip rings and stem design can make a cup easier or harder to reach and hold.

A soft bell-shaped cup may feel very different from a firm bell-shaped cup of the same size. Shape works together with diameter, length and firmness—not in isolation.

Menstrual cup shape comparison

Shape	Defining Features	May Be Worth Considering If...	Keep in Mind
Bell-shaped	Flared rim with a rounded body	You want a familiar, versatile starting shape	Diameter and firmness vary considerably between brands; do not assume all bell-shaped cups feel the same.
V-shaped	Gradually tapered body with a narrower base	You prefer a tapered base or have an average-to-high cervix	Capacity and overall length vary by model; check measurements rather than relying on shape alone.
Narrow	Long, slim body with a tapered base	You have a medium-to-high cervix or prefer a narrower profile	May be too long for a low cervix if the cup sits beyond easy reach.
Round	Short, bulb-shaped body with a full lower section	You have a low-to-average cervix or want capacity in a shorter cup	A wider or firmer body may create pressure for some users; compare diameter and firmness carefully.
U-shaped	Straighter sides with a broadly rounded base	You prefer a rounded lower body or an easy-to-locate loop stem	Always release the seal before removal; stem design varies by brand.
Asymmetrical	Curved or uneven body with an offset base	Standard cups sit at an angle or create pressure despite correct fit	Try it as an option rather than an anatomical guarantee; evidence is mainly anecdotal.
Collapsible	Accordion-style body that folds for storage	Portability and discreet storage are priorities	Ensure all folds open completely before use; clean carefully between storage and use.

Menstrual cup shapes

1. Bell-shaped menstrual cups

Bell-shaped cups usually have a flared or pronounced rim, gently rounded sides and a base that narrows towards a short stem or nib. This is one of the most common cup profiles and is often a practical starting point. Bell-shaped cups are available in many different lengths, diameters and firmness levels.

A bell-shaped cup may be worth considering if:

• You have an average cervix height
• You want a widely available, familiar cup design
• You prefer a rounded body with a distinct base to grip
• You want several size or firmness choices in a similar shape

Keep in mind

Bell-shaped describes the general silhouette, not the firmness or exact dimensions. One bell-shaped cup may be short and soft, while another may be longer, wider or considerably firmer. If you are sensitive to bladder or urethral pressure, look carefully at both the rim firmness and widest diameter rather than assuming every bell-shaped cup will feel the same.

Bell-shaped cups at Period Shop

2. V-shaped menstrual cups

V-shaped cups taper progressively from the rim towards a narrower base. This creates the familiar triangular silhouette many people associate with menstrual cups. Some brands describe this general profile as bell-shaped or classically shaped, which demonstrates how much the categories can overlap.

A V-shaped cup may be worth considering if:

• You prefer a gradually tapered body
• You want a narrower base to pinch during removal
• You have an average-to-high cervix, depending on the cup's length
• You prefer a traditional straight stem that can be trimmed where permitted

Keep in mind

A tapered body does not necessarily mean the cup has a small diameter. Check the rim diameter separately. Two V-shaped cups that look similar from the outside may have different wall thicknesses, internal volumes or suction-hole positions.

V-shaped and tapered cups at Period Shop

3. Narrow menstrual cups

Narrow cups generally have a long, slim body that tapers towards the base. Some also have an angled rim or an elongated body intended to make the cup easier to reach when the cervix sits higher.

A narrow cup may be worth considering if:

• You have a medium-to-high cervix
• Short cups tend to move beyond easy reach
• Wider cups create an uncomfortable feeling of pressure
• You prefer a longer cup that is easier to reach without relying on the stem

The long body can make this shape easier to reach when the cervix sits higher during menstruation. Its narrower profile may also feel less bulky, although diameter and firmness will have a greater influence on pressure than shape alone.

Keep in mind

A long narrow cup may not suit a low cervix. If the cup is longer than the available space, the base or stem may sit too close to the vaginal opening and may irritate. An angled rim does not necessarily need to face a particular direction unless the manufacturer's instructions say otherwise.

Narrow and elongated cups at Period Shop

4. Round menstrual cups

Round cups have a short, bulbous body that remains relatively full through the lower section. This can provide useful capacity without requiring a long cup. The Merula One Size is a distinctive example, with a listed capacity of 38 ml.

A round cup may be worth considering if:

• You have a low-to-average cervix
• Long cups tend to protrude or feel uncomfortable
• You need greater capacity in a relatively short cup
• Softer cups tend to remain folded or are difficult for you to open
• Keep in mind

Keep in mind

Round cups can be wider through the body than tapered cups. If you are sensitive to pressure, compare the diameter and firmness carefully. Capacity depends on internal volume, placement of suction-release holes and body shape—not outside appearance.

Round cups at Period Shop

5. U-shaped menstrual cups

U-shaped cups generally have straighter upper sides and a broad, rounded lower body. Some include a loop-style stem that can make the cup easier to locate.

A U-shaped cup may be worth considering if:

• You prefer a rounded lower body rather than a sharply tapered base
• You want a clearly defined base to pinch during removal
• A loop stem is easier for you to locate
• You prefer a cup that feels stable through the lower body

About loop stems

A loop can help you locate the cup and steady it while bringing it lower. However, always release the cup's seal before removing it. Pinch the base or press one side of the cup inward, then gently ease it down. Pulling firmly on a loop while the cup remains sealed may cause discomfort. Stem and loop designs vary by brand, so always follow the instructions supplied with your cup.

U-shaped and loop-stem cups at Period Shop

6. Asymmetrical menstrual cups

Asymmetrical cups have an uneven, curved or offset body rather than two matching sides. The base and stem may sit slightly off-centre.

An asymmetrical cup may be worth considering if:

• A standard cup naturally sits at an angle
• You consistently feel pressure on one side
• Your cervix points towards one side during menstruation
• Symmetrical cups have been comfortable on one side but uncomfortable on the other
• You have a tilted uterus

Keep in mind

Having a tilted or retroverted uterus does not automatically mean you need an asymmetrical cup. The position and height of the cervix during menstruation are generally more directly relevant to cup fit than the overall direction of the uterus. There is anecdotal evidence that an asymmetrical cup feels better for some people with a tilted uterus; however, there is not enough clinical evidence to say that this shape will reliably solve leakage or discomfort associated with a tilted uterus or cervix. Consider it an option to try rather than a guaranteed anatomical match.

Asymmetrical cups at Period Shop

7. Collapsible menstrual cups

Collapsible cups use an accordion-style body that folds down into a compact shape for storage. When opened for use, they function like other menstrual cups. The Lily Cup Compact folds flat into its storage case with a reinforced rim designed to help it open.

A collapsible cup may be worth considering if:

• You want a cup that is easy to carry in a handbag, pocket or travel kit
• You have a low-to-average cervix and need a shorter cup
• Portability and discreet storage are priorities

Keep in mind

Make sure every collapsible section is fully extended before insertion and after insertion, check that the cup has opened completely. The folds and ridges also need careful cleaning. Follow the manufacturer's care instructions and inspect the folds for any trapped residue before storing the cup.

Collapsible cups at Period Shop

Stem shape can vary by brand

Cup stems come in several designs: solid cylindrical-style stems (with or without ribs for grip), hollow tube-style stems (with or without ribs for grip), flat tabs (with or without ribs for grip), pointy stems (with or without ribs for grip), rounded nibs, loops or rings, ladder-style stems, ball stems, and stemless options.

The stem helps you locate the cup as you move it lower in the vaginal canal but it is not the main removal mechanism. Always pinch or press the cup's base (or one side) to release the seal first, then gently ease it out. Pulling hard on the stem while the cup remains sealed may cause discomfort.

For stemless cups, locate the cup by feeling the base or grip rings, then use the same seal-release technique before removal. Some stems can be trimmed, while others should not be altered. Check the manufacturer's instructions before cutting a stem, particularly if it has a loop, ladder or hollow design.

Shape is only one part of choosing a cup

While shape can guide your initial choice, the following factors are equally important—and often more predictive of comfort.

1. Cervix height

Cervix height is one of the most useful starting points when selecting cup length. You can check it during your period by washing your hands and gently inserting a finger into the vagina until you feel the cervix. It usually feels firmer than the surrounding vaginal tissue and may feel similar to the tip of a nose, with a small dimple in the centre.

Rather than relying only on finger-joint guides, consider measuring the distance reached on your finger, as finger lengths vary considerably. Check on more than one day of your period because cervix position can shift throughout the cycle.

• Lower cervix: Look at shorter cups or cups with a short, trimmable stem.
• Average cervix: You may have the widest range of suitable lengths.
• Higher cervix: A longer cup or accessible stem may make removal easier.

The cup should be fully inside the vagina without the base or stem rubbing at the opening.

2. Cup length

Check both the body length and total length, including the stem. A cup that is too long may protrude or create pressure. A cup that is too short may travel beyond easy reach, particularly if you have a high cervix. A stem can sometimes be shortened, but shortening it will not change the length of the cup's body.

3. Diameter

Diameter describes the width of the cup, usually measured across the rim. A larger diameter may help some cups remain in place, but it may create pressure for someone with a sensitive bladder, urethra or vaginal canal. A smaller diameter may feel more comfortable but still needs to open and form an effective seal. Do not assume that the smaller size from every brand has the same diameter—cup sizing is not standardised.

4. Firmness

Firmness affects how readily a cup opens and how much pressure it may apply to surrounding tissue.

A firmer cup may open more readily, be useful during exercise or with stronger pelvic floor muscles, and feel more noticeable.

A softer cup may feel gentler for people who are pressure-sensitive, require more care to open completely, and be more likely to remain partially folded for some users.

The rim and body can also have different firmness levels. A cup may have a firm opening rim but a softer body.

5. Capacity

If you have a heavier flow, compare the capacity to the suction-release holes rather than relying only on the cup's overall stated volume. A cup's outside appearance is not a reliable guide to capacity—research has found no consistent relationship between shape and volume.

Remember that the safe wear time listed by the manufacturer is a maximum. You may need to empty the cup more frequently on heavier days.

6. Your removal preferences

Consider how easily you can reach, grip and pinch the cup. A loop or ladder may make the cup easier to locate, but you still need to release the seal. Grip rings or a textured base may help if the cup becomes slippery during removal.

People with reduced hand mobility, a high cervix or difficulty bearing down may benefit from paying particular attention to cup length and base design.

What a well-fitting menstrual cup should feel like

A suitable cup should sit fully inside the vagina, feel comfortable during ordinary movement, open without excessive manipulation, remain in position without slipping, collect flow without persistent unexplained leaks, be reachable when it is time to remove it, and allow you to urinate normally without significant pressure.

You may be aware of a new cup while learning to use it, but it should not cause ongoing pain.

Troubleshooting cup fit

What You Notice	Possible Explanation	What to Consider
The stem pokes or rubs	The cup may be too long or the stem may need adjustment	Check total length and follow the manufacturer's stem-trimming instructions
The cup is difficult to reach	The cup may be too short for your cervix height	Consider a longer cup or a more accessible stem
Bladder pressure or slow urination	The cup may be too wide, too firm or sitting in an uncomfortable position	Try repositioning it or consider a softer or narrower cup
The cup will not open	It may be too soft for your body, still folded or positioned in limited space	Try another fold, rotate the cup or consider a firmer rim
The cup slips down	The diameter, shape or firmness may not be providing a stable fit	Compare a different diameter or body profile
The cup leaks	It may not be open, the cervix may be outside the rim or the cup may be full	Check placement and capacity before changing shape
Removal is painful	The seal may not be fully released	Pinch the base or press in one side before gently removing it

Persistent leakage does not always mean you have chosen the wrong shape. Technique, placement and capacity should be checked first.

Frequently asked questions

Is one menstrual cup shape best for beginners?

No single shape is best for every beginner. A cup that is easy to fold, opens reliably and matches your cervix height is generally more useful than choosing by shape alone. Soft cups may feel gentle but sometimes require more practice to open. Firmer cups may open more readily but can feel more noticeable.

Does a tilted uterus require an asymmetrical cup?

Not necessarily. A tilted uterus describes the direction of the uterus, but cup fit is more directly influenced by the position of the cervix and the available space in the vaginal canal. Some people may prefer an asymmetrical or rounded cup, but there is not enough evidence to guarantee that a particular shape will work because the uterus is tilted.

Does a round cup always have more capacity?

No. Round cups can provide good capacity in a shorter body, but capacity depends on the cup's internal dimensions, wall thickness and hole placement. Always check the capacity stated for the individual model.

Can I cut the stem off my cup?

Some manufacturers allow stems to be shortened or completely removed. Others use a stem design that should not be altered. Try the cup before trimming it, cut only a small amount at a time and make sure no sharp edges remain. Never cut into the cup's body.

Can a menstrual cup get lost?

No. The vagina is a closed canal, so the cup cannot travel into the abdomen. It can move higher and become harder to reach, particularly with a high cervix. Relax, use your pelvic floor muscles to gently bear down and break the seal before removing the cup. Seek medical assistance if you cannot remove it or experience significant pain.

The bottom line

Menstrual cup shape can influence how a cup sits, opens and feels, but it is most useful as a starting point rather than the sole basis for your choice.

Start with your cervix height, then compare cup body length, total length including the stem, rim diameter, body and rim firmness, capacity, and base and stem design.

Use shape to narrow the options rather than expecting it to predict a perfect fit.

There can be a learning curve when moving to a menstrual cup. Discomfort during insertion and removal in the first cycle is common—it usually improves with practice and familiarity. A major systematic review found that many users needed practice and support during the first few cycles. Around 70-73 percent of users wanted to continue using cups once they became familiar with them. Menstrual cups were generally found to be a safe option, with leakage similar to or lower than disposable products in the studies that directly compared them.

You can browse Period Shop’s complete range of menstrual cups and compare the measurements, firmness, capacity and design features of each model. If you are unsure where to begin, contact Period Shop for practical product guidance.

If you are unsure where to begin, contact Period Shop for practical product guidance.

Important health information

Always follow the instructions supplied with your menstrual cup.

Seek advice from a qualified health professional if you have ongoing pain, difficulty urinating, unexplained bleeding, recurrent infections, or difficulty removing a cup.

You should also seek individual advice before using a menstrual cup if you have recently given birth, have had pelvic surgery, have a pelvic health condition, or use an intrauterine device (IUD). Some research suggests a possible increased risk of IUD expulsion with menstrual cup use.

This information is general and is not a substitute for individual medical advice.

References

• van Eijk AM, et al. Menstrual cup use, leakage, acceptability, safety and availability: a systematic review and meta-analysis. The Lancet Public Health. 2019.
• Manley H, et al. Comparison between menstrual cups: first step to categorisation and improved safety. Women’s Health. 2021.
• Arenas-Gallo C, et al. Acceptability and safety of the menstrual cup: a systematic review of the literature. 2020.