7 Factors in Picking the Right Menstrual Cup

Before I tried a menstrual cup, I bled all over my bed every month. Pads and tampons consistently failed to contain my heavy flow.

Fuck that shit.

Menstrual cups have been an absolute GODSEND for me. They are the PEAK of con­ve­nience for the right users.

But the lack of infor­ma­tion in pick­ing the right men­stru­al cup for you often drove me bonkers.

Two cup sizes are usually marketed:

1. A small­er one for peo­ple who are under 25 and haven't giv­en birth
2. A big­ger one for peo­ple over 25 or have giv­en birth.

So to the layper­son, men­stru­al cup fit may sound like it's about hav­ing a tight vs. loose vagi­na. That's not the case, though.

Consider these other, potentially more relevant factors in choosing the right menstrual cup fit.

Table of contents

• Menstrual cup fit factors 
  • Cervix width
  • Resting vagi­na length
  • Menstrual flow
  • Changes through­out your period
  • Pelvic floor strength
  • Is your vagi­na eas­i­ly irritated?
• A start­ing point: sil­i­cone men­stru­al cup kits
• What's the best men­stru­al cup for yours truly?

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1. Cervix width

Cervix shapes vary from per­son to per­son — there's a big range of "nor­mal!" Some are nar­row and pointy, while oth­ers are wider, rounder, more open, etc. And if your cervix is on the big­ger side, you'll want a men­stru­al cup that can seal over it to col­lect blood.

While it's true that your cervix gen­er­al­ly gets wider as you grow old­er or give birth, the cor­re­la­tion is not absolute. I'm over 25, and my cervix is still slen­der and tapered. Think of the stan­dard siz­ing guide­lines as more of a start­ing point.

What to look at

What's the men­stru­al cup's diam­e­ter and shape? And how does that com­pare to your cervix's shape and size?

I under­stand: the constantly-​shifting inter­nal anato­my is hard to mea­sure. So if you don't know how your cervix looks or can't reach to feel it, con­sid­er view­ing it with a (clean!) specu­lum, hand mir­ror, and flashlight.

2. Cervix height/resting vagina length

Oh gosh, I wish my younger self knew about cervix height's effect on men­stru­al cup fit. The gist is that the high­er your cervix is, the more you'd ben­e­fit from a long one.

It's not that you can't use a short men­stru­al cup with a high-​set cervix. It's just that the device may ride up and be hard­er to reach in and remove. The vagi­na is a finite space; things won't get "lost" in it. However, the strug­gle of pulling out an ill-​fitting men­stru­al cup is very real.

On the flip side, if you have a low-​set cervix or short vagi­na at rest, a long men­stru­al cup may not entire­ly fit inside. And hav­ing sil­i­cone pok­ing out of you isn't the most com­fort­able or con­ve­nient thing to deal with.

What to look at

When insert­ing your mid­dle or fore­fin­gers, how far can you go in before feel­ing your cervix? If you encounter it before the sec­ond knuck­le, a short­er men­stru­al cup may work bet­ter for you. If you can go past that (or all the way in), a longer one will be far eas­i­er to use!

Consider the cup's total length com­pared to that, if you're going to use the stem for removal. You may choose to trim it for com­fort, though.

3. Menstrual flow

If you have a heavy flow, a larg­er cup means you'll have to emp­ty it (or worse, deal with leaks) less often. If you have a light flow, a small cup might ful­fill your needs just fine, while being more comfortable.

Ah, yes! Another rea­son I wish I said, "Fuck it" to the men­stru­al cup siz­ing guide­lines before. I had a heavy flow long before I was 25.

What to look at

How often do you change your pads or tam­pons? How quick­ly do they fill up?

4. Changes throughout your period

The pre­vi­ous three fac­tors aren't nec­es­sar­i­ly sta­t­ic through­out your peri­od. You may find that your cervix gets high­er or flow gets dra­mat­i­cal­ly lighter, for example.

Some men­stru­al cup users pre­fer to have two sizes that they wear on dif­fer­ent days. The choice is all about you and your body.

5. Pelvic floor strength

Menstrual cups vary in not just shape and size, but also firm­ness. Stiffer ones form a tighter seal. I've seen advice that the soft­er ones are bet­ter for those who haven't giv­en birth, and vice versa.

On the con­trary, I've done vagi­nal weightlift­ing but found that firm men­stru­al cup rings work bet­ter for me. It's like I can eas­i­ly break the seal of a soft­er one when clench­ing or bear­ing down.

Fold a men­stru­al cup before insert­ing it. It will spring open and form a seal.

Further reading

• Guide to Kegel Progression & Vaginal Weightlifting
• Why a tight vagi­na isn't the same thing as a strong one

6. Is your vagina easily irritated?

I men­tioned before that some users might find a small­er or squishi­er men­stru­al cup more com­fort­able — it places less pres­sure on the wearer's walls and blad­der. If a small cup still col­lects blood well enough and works for you, have at it.

7. Impulsive period sex

I know: hav­ing sex in a tent while wear­ing a men­stru­al cup is odd­ly spe­cif­ic. My boyfriend and I were horny and tried it — and we both enjoyed the experience.

I was wear­ing a short, round­ed one with a min­i­mal retrieval stem (more like a nub) at the time. It's a pain in the ass for me to take out, and it's not the best for day wear… but it left my boyfriend's cock plen­ty of room to thrust!

The tiny stem was pushed a bit to the side, not pok­ing him at all. My cervix and A‑spot still felt plen­ty of sen­sa­tion to reach orgasm via deep pen­e­tra­tion.

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Summary of how to choose a menstrual cup

I know that's a lot of infor­ma­tion. Let's dis­till it, so you don't get overwhelmed.

Shape and sizing tips

• Get a cup that fits your cervix width and rest­ing vagi­nal length.
• An immense flow means a big­ger cup is more convenient.
• Soft men­stru­al cups are more com­fort­able, but firm ones main­tain the seal better.
• Don't be afraid to use dif­fer­ent sizes on dif­fer­ent days.

Yes, intercourse and cervical orgasms are still possible while wearing a menstrual cup.

• I wouldn't rec­om­mend the Instead Softcup for that, despite their marketing.
• Get one that takes up less space in the vagi­nal canal.
• I know nobody asked, but it's good to know.

Overall, say "Fuck it" to absolute rules about menstrual cup fit. Listen to your body.

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A starting point: menstrual cup sampler kits

Kits you may see in sex boutiques include:

• Fun Factory's Fun Cup Kits 
  • Two of size A
  • Two of size B
  • One of each size
• Jimmyjane's Intimate Care cup set 
  • One of each size (both clear or purple)

And of course, you can find the ubiq­ui­tous Diva Cup in drug­stores and some health food stores.

There's a boun­ti­ful vari­ety out there, so this list isn't at all com­pre­hen­sive; shop around to see what works for you!

Here's a quick summary of the menstrual cup measurements

	Capacity	Diameter	Length	Firmness
Fun Factory Fun Cup Size B	30 mL 🤩	1.7"	2.29"	Firm but flexible rim with thin cup
Fun Factory Fun Cup Size A	20 mL	1.56"	2.1"	Firm but flexible rim. Cup isn't as bendy as with Size B.
Jimmyjane Intimate Care Regular	21 mL	1.8"	2.6" (65mm) with stem / 2" (50mm) without stem	Still bendy but firmer and thicker than the Fun Cups.
Jimmyjane Intimate Care Small	14 mL	1.7"	2.2" (55mm) with stem/ 1.6" (40mm) without stem	Still bendy but firmer and thicker than the Fun Cups.

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What do I think is the best menstrual cup?

Of the four cups above, Fun Factory's Fun Cup Size B was the best fit for me.

Here's why I love the large Fun Cups so much:

• Collects sub­stan­tial­ly more blood than the others
• The cup's tapered shape doesn't ride up as easily.
• I rarely actu­al­ly use the retrieval stems anyway.
• Firm rim main­tains the seal
• The thin cup is oth­er­wise super comfy

My pref­er­ences don't mean that the Fun Factory Fun Cups will be the best men­stru­al cup fit for you. Not every­one likes the angling, for exam­ple. However, they're a fan­tas­tic option to con­sid­er for some­one with a long vagi­na and heavy flow, like me.

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Wrapping it up

The most impor­tant rule to remem­ber is that there are no hard-​and-​fast rules. Just as sex toy pref­er­ences vary, so do opin­ions on the best men­stru­al cups!

Ultimately though, as long as my cup works, I'd choose that over a tra­di­tion­al tam­pon or pad most days. FUCK YEAH, clean sheets, min­i­mal main­te­nance, and danc­ing with no wor­ries about my period.

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Thank you to Betty's Toy Box for spon­sor­ing this post. <3

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